Activity and safety of enobosarm, a novel, oral, selective androgen receptor modulator, in androgen receptor-positive, oestrogen receptor-positive, and HER2-negative advanced breast cancer (Study G200802): a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial

BACKGROUND

The androgen receptor is a tumour suppressor in oestrogen receptor-positive breast cancer. The activity and safety of enobosarm, an oral selective androgen receptor modulator, was evaluated in women with oestrogen receptor (ER)-positive, HER2-negative, and androgen receptor (AR)-positive disease.

METHODS

Women who were postmenopausal (aged ≥18 years) with previously treated ER-positive, HER2-negative, locally advanced or metastatic breast cancer with an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled in a randomised, open-label, multicentre, multinational, parallel design, phase 2 trial done at 35 cancer treatment centres in nine countries. Participants were stratified on the setting of immediately preceding endocrine therapy and the presence of bone-only metastasis and randomly assigned (1:1) to 9 mg or 18 mg oral enobosarm daily using an interactive web response system. The primary endpoint was clinical benefit rate at 24 weeks in those with centrally confirmed AR-positive disease (ie, the evaluable population). This trial is registered with ClinicalTrials.gov (NCT02463032).

FINDINGS

Between Sept 10, 2015, and Nov 28, 2017, 136 (79%) of 172 patients deemed eligible were randomly assigned to 9 mg (n=72) or 18 mg (n=64) oral enobosarm daily. Of these 136 patients, 102 (75%) patients formed the evaluable population (9 mg, n=50; 18 mg, n=52). The median age was 60·5 years (IQR 52·3-69·3) in the 9 mg group and 62·5 years (54·0-69·3) in the 18 mg group. The median follow-up was 7·5 months (IQR 2·9-14·1). At 24 weeks, 16 (32%, 95% CI 20-47) of 50 in the 9 mg group and 15 (29%, 17-43) of 52 in the 18 mg group had clinical benefit. Six (8%) of 75 patients who received 9 mg and ten (16%) of 61 patients who received 18 mg had grade 3 or grade 4 drug-related adverse events, most frequently increased hepatic transaminases (three [4%] of 75 in the 9 mg group and two [3%] of 61 in the 18 mg group), hypercalcaemia (two [3%] and two [3%]), and fatigue (one [1%] and two [3%]). Four deaths (one in the 9 mg group and three in the 18 mg group) were deemed unrelated to the study drug.

INTERPRETATION

Enobosarm has anti-tumour activity in patients with ER-positive, HER2-negative advanced breast cancer, showing that AR activation can result in clinical benefit, supporting further clinical investigation of selective AR activation strategies for the treatment of AR-positive, ER-positive, HER2-negative advanced breast cancer.

FUNDING

GTx.

Silent suffering: the impact of sexual health challenges on patient-clinician communication and adherence to adjuvant endocrine therapy among Black women with early-stage breast cancer

PURPOSE

Adjuvant endocrine therapy (AET) increases sexual health challenges for women with early-stage breast cancer. Black women are more likely than women of other racial/ethnic groups to report adverse symptoms and least likely to initiate and maintain AET. Little is known about how sexual health challenges influence patient-clinician communication and treatment adherence. This study explores facilitators of and barriers to patient-clinician communication about sexual health and how those factors might affect AET adherence among Black women with early-stage breast cancer.

METHODS

We conducted 32 semi-structured, in-depth interviews among Black women with early-stage breast cancer in the U.S. Mid-South region. Participants completed an online questionnaire prior to interviews. Data were analyzed using thematic analysis.

RESULTS

Participants' median age was 59 (range 40-78 years, SD = 9.0). Adverse sexual symptoms hindered participants' AET adherence. Facilitators of patient-clinician communication about sexual health included female clinicians and peer support. Barriers included perceptions of male oncologists' disinterest in Black women's sexual health, perceptions of male oncologists' biased beliefs about sexual activity among older Black women, cultural norms of sexual silence among Southern Black women, and medical mistrust.

CONCLUSIONS

Adverse sexual symptoms and poor patient-clinician communication about sexual health contribute to lower AET adherence among Black women with early-stage breast cancer. New interventions using peer support models and female clinicians trained to discuss sexual health could ameliorate communication barriers and improve treatment adherence.

IMPLICATIONS FOR CANCER SURVIVORS

Black women with early-stage breast cancer in the U.S. Mid-South may require additional resources to address sociocultural and psychosocial implications of cancer survivorship to enable candid discussions with oncologists.

Lasofoxifene versus fulvestrant for ER+/HER2- metastatic breast cancer with an ESR1 mutation: results from the randomized, phase II ELAINE 1 trial

BACKGROUND

Acquired estrogen receptor alpha (ER/ESR1) mutations commonly cause endocrine resistance in ER+ metastatic breast cancer (mBC). Lasofoxifene, a novel selective ER modulator, stabilizes an antagonist conformation of wild-type and ESR1-mutated ER-ligand binding domains, and has antitumor activity in ESR1-mutated xenografts.

PATIENTS AND METHODS

In this open-label, randomized, phase II, multicenter, ELAINE 1 study (NCT03781063), we randomized women with ESR1-mutated, ER+/human epidermal growth factor receptor 2 negative (HER2-) mBC that had progressed on an aromatase inhibitor (AI) plus a cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) to oral lasofoxifene 5 mg daily or IM fulvestrant 500 mg (days 1, 15, and 29, and then every 4 weeks) until disease progression/toxicity. The primary endpoint was progression-free survival (PFS); secondary endpoints were safety/tolerability.

RESULTS

A total of 103 patients received lasofoxifene (n = 52) or fulvestrant (n = 51). The most current efficacy analysis showed that lasofoxifene did not significantly prolong median PFS compared with fulvestrant: 24.2 weeks (∼5.6 months) versus 16.2 weeks (∼3.7 months; P = 0.138); hazard ratio 0.699 (95% confidence interval 0.434-1.125). However, PFS and other clinical endpoints numerically favored lasofoxifene: clinical benefit rate (36.5% versus 21.6%; P = 0.117), objective response rate [13.2% (including a complete response in one lasofoxifene-treated patient) versus 2.9%; P = 0.124], and 6-month (53.4% versus 37.9%) and 12-month (30.7% versus 14.1%) PFS rates. Most common treatment-emergent adverse events with lasofoxifene were nausea, fatigue, arthralgia, and hot flushes. One death occurred in the fulvestrant arm. Circulating tumor DNA ESR1 mutant allele fraction (MAF) decreased from baseline to week 8 in 82.9% of evaluable lasofoxifene-treated versus 61.5% of fulvestrant-treated patients.

CONCLUSIONS

Lasofoxifene demonstrated encouraging antitumor activity versus fulvestrant and was well tolerated in patients with ESR1-mutated, endocrine-resistant mBC following progression on AI plus CDK4/6i. Consistent with target engagement, lasofoxifene reduced ESR1 MAF, and to a greater extent than fulvestrant. Lasofoxifene may be a promising targeted treatment for patients with ESR1-mutated mBC and warrants further investigation.

Mobile application to support oncology patients during treatment on patient outcomes: Evidence from a randomized controlled trial

BACKGROUND

Cancer treatment requires substantial demands on patients and their caregivers. Mobile apps can provide support for self-management during oncology treatment, but few have been rigorously evaluated.

METHODS

A 3-month randomized controlled trial was conducted at a large cancer center to evaluate the efficacy of an app (LivingWith®) that provides self-management support during cancer treatment on quality of life and health care utilization. Patients in chemotherapy treatment were randomized into the intervention (n = 113) and control group (n = 111). Intervention group participants agreed to use the app weekly for 3 months, and all participants completed a survey at enrollment and after 3 months to evaluate changes in quality of life and health care utilization.

RESULTS

Retention rate was 75.4% with 169 participants completing the follow-up survey. The intervention group reported 0.74 fewer medical office visits (p = 0.043) and 0.24 fewer visits with a mental health professional (p = 0.061) during the 3 and month intervention compared with controls. There were no significant changes by study group in quality of life, or emergency room and urgent care visits. Among intervention participants, 75.3% reported using the app and on average, used it 11.7 times during the 3-month intervention. Reasons for not using the app among intervention participants included lack of time, lack of interest in apps, and usability challenges.

CONCLUSIONS AND RELEVANCE

Apps are inexpensive and scalable tools that can provide additional support for individuals coping with complex cancer treatments. This trial provides evidence that a well-designed oncology support app used during chemotherapy resulted in fewer clinic visits. Still, nearly a quarter of participants randomized to the intervention arm reported never using the app due to personal preference and usability challenges, which points to future opportunities for calibrating target user population and improving user-centered design.

CLINICALTRIALS

gov identifier: NCT04331678.

Race Differences in Patient-Reported Symptoms during Chemotherapy among Women with Early-Stage Hormone Receptor-Positive Breast Cancer

BACKGROUND

Symptom burden differences may contribute to racial disparities in breast cancer survival. We compared symptom changes from before to during chemotherapy among women with breast cancer.

METHODS

This observational study followed a cohort of Black and White women diagnosed with Stage I-III, hormone receptor-positive breast cancer from a large cancer center in 2007 to 2015, and reported symptoms before and during chemotherapy. We identified patients who experienced a one-standard deviation (SD) increase in symptom burden after starting chemotherapy using four validated composite scores (General Physical Symptoms, Treatment Side Effects, Acute Distress, and Despair). Kitagawa-Blinder-Oaxaca decomposition was used to quantify race differences in symptom changes explained by baseline characteristics (sociodemographic, baseline scores, cancer stage) and first-line chemotherapy regimens.

RESULTS

Among 1,273 patients, Black women (n = 405, 31.8%) were more likely to report one-SD increase in General Physical Symptoms (55.6% vs. 48.2%, P = 0.015), Treatment Side Effects (74.0% vs. 63.4%, P < 0.001), and Acute Distress (27.4% vs. 20.0%, P = 0.010) than White women. Baseline characteristics and first-line chemotherapy regimens explained a large and significant proportion of the difference in Acute Distress changes (93.7%, P = 0.001), but not General Physical Symptoms (25.7%, P = 0.25) or Treatment Side Effects (16.4%, P = 0.28).

CONCLUSIONS

Black women with early-stage breast cancer were more likely to experience significant increases in physical and psychological symptom burden during chemotherapy. Most of the difference in physical symptom changes remained unexplained by baseline characteristics, which suggests inadequate symptom management among Black women.

IMPACT

Future studies should identify strategies to improve symptom management among Black women and reduce differences in symptom burden. See related commentary by Rosenzweig and Mazanec, p. 157.

An examination of health care utilization during the COVID-19 pandemic among women with early-stage hormone receptor-positive breast cancer

BACKGROUND

Women undergoing treatment for breast cancer require frequent clinic visits for maintenance of therapy. With COVID-19 causing health care disruptions, it is important to learn about how this population's access to health care has changed. This study compares self-reported health care utilization and changes in factors related to health care access among women treated at a cancer center in the mid-South US before and during the pandemic.

METHODS

Participants (N = 306) part of a longitudinal study to improve adjuvant endocrine therapy (AET) adherence completed pre-intervention baseline surveys about their health care utilization prior to AET initiation. Questions about the impact of COVID-19 were added after the pandemic started assessing financial loss and factors related to care. Participants were categorized into three time periods based on the survey completion date: (1) pre-COVID (December 2018 to March 2020), (2) early COVID (April 2020 - December 2020), and later COVID (January 2021 to June 2021). Negative binomial regression analyses used to compare health care utilization at different phases of the pandemic controlling for patient characteristics.

RESULTS

Adjusted analyses indicated office visits declined from pre-COVID, with an adjusted average of 17.7 visits, to 12.1 visits during the early COVID period (p = 0.01) and 9.9 visits during the later COVID period (p < 0.01). Hospitalizations declined from an adjusted average 0.45 admissions during early COVID to 0.21 during later COVID, after vaccines became available (p = 0.05). Among COVID period participants, the proportion reporting changes/gaps in health insurance coverage increased from 9.5% participants during early-COVID to 14.8% in the later-COVID period (p = 0.05). The proportion reporting financial loss due to the pandemic was similar during both COVID periods (34.3% early- and 37.7% later-COVID, p = 0.72). The proportion of participants reporting delaying care or refilling prescriptions decreased from 15.2% in early-COVID to 4.9% in the later-COVID period (p = 0.04).

CONCLUSION

COVID-19 caused disruptions to routine health care for women with breast cancer. Patients reported having fewer office visits at the start of the pandemic that continued to decrease even after vaccines were available. Fewer patients reported delaying in-person care as the pandemic progressed.

Expert consensus recommendations for managing hyperglycemia and rash in patients with PIK3CA-mutated, hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) advanced breast cancer (ABC) treated with alpelisib (ALP)

422

Background: ALP is a PI3Kα inhibitor and degrader approved with fulvestrant for the treatment (tx) of patients (pts) with PIK3CA-mutated, HR+, HER2– ABC. Hyperglycemia (HG) and rash are expected adverse events with ALP tx and remain a challenge for physicians and pts. Management guidance is primarily based on clinical trial experience, which is not necessarily reflective of real-world pts. Here we report guidance for optimizing prevention and management of HG and rash in pts taking ALP based on an integrated Delphi panel, a systematic, validated approach to organize consensus from experts in the absence of definitive evidence. Methods: Two modified Delphi panels were conducted, focusing on HG and rash, respectively. Each panel included 4 oncologists, 4 endocrinologists or dermatologists, 1 clinical pharmacist, and 1 pt advocate. Experts were asked to rate appropriateness of 908 interventions for HG and 348 for rash on hypothetical pt scenarios on a 1 (highly inappropriate) to 9 (highly appropriate) scale. Results were reviewed at virtual meetings, after which experts repeated the rating. The level of agreement or disagreement was determined using the median scores and dispersion from the final rating, and this level of agreement was used to develop consensus statements and tx algorithms. Results: Per the HG panel, (a) ALP tx is appropriate in individuals with HbA1c 6.5% to < 8% with a pre-tx endocrinology consult; (b) low carbohydrate diet is appropriate in all pts starting ALP; (c) prophylactic metformin is appropriate in pts with baseline HbA1c 5.7%-6.4%; may also be appropriate in pts with HbA1c < 5.7%; (d) after metformin, an SGLT2 inhibitor or a thiazolidinedione is an appropriate second-/third-line anti-HG agent (or first-line in metformin-intolerant pts), while insulin is not. Per the rash panel, (a) prophylactic nonsedating (NS) H1 antihistamines (standard dose) are appropriate for all pts; (b) starting/escalating NS H1 antihistamines and topical steroids (TS) is the preferred first step for managing rash; (c) it is appropriate to add, but not replace with, a sedating H1 antihistamine, if response to high-dose, NS option is inadequate, and to add an H2 antihistamine if response is still inadequate; (d) it is appropriate to hold ALP and start oral corticosteroids (OCS) if rash affects > 30% body surface area and is recurrent or has moderate/severe symptoms; (e) if angioedema is present, it is appropriate to either hold ALP and start OCS, or permanently discontinue ALP tx. Conclusions: Until further evidence is available, these expert recommendations provide guidance on prevention and management of HG and rash related to ALP tx in routine clinical practice.

Complementary Roles for Tissue- and Blood-Based Comprehensive Genomic Profiling for Detection of Actionable Driver Alterations in Advanced NSCLC

Introduction

Whereas tumor biopsy is the reference standard for genomic profiling of advanced NSCLC, there are now multiple assays approved by the Food and Drug Administration for liquid biopsy testing of circulating tumor DNA. Here, we study the incremental value that liquid biopsy comprehensive genomic profiling (CGP) adds to tissue molecular testing.

Methods

Patients with metastatic NSCLC were enrolled in a prospective diagnostic study to receive circulating tumor DNA CGP; tissue CGP was optional in addition to their standard tissue testing. Focusing on nine genes listed per the National Comprehensive Cancer Network (NCCN) guidelines, liquid CGP was compared with available tissue testing results across three subcohorts: tissue CGP, standard-of-care testing of up to five biomarkers, or no tissue testing.

Results

A total of 515 patients with advanced nonsquamous NSCLC received liquid CGP. Among 131 with tissue CGP results, NCCN biomarkers were detected in 86 (66%) with tissue CGP and 56 (43%) with liquid CGP (p < 0.001). Adding liquid CGP to tissue CGP detected no additional patients with NCCN biomarkers, whereas tissue CGP detected NCCN biomarkers in 30 patients (23%) missed by liquid CGP. Studying 264 patients receiving tissue testing of up to five genes, 102 (39%) had NCCN biomarkers detected in tissue, with an additional 48 (18%) detected using liquid CGP, including 18 with RET, MET, or ERBB2 drivers not studied in tissue.

Conclusions

For the detection of patients with advanced nonsquamous NSCLC harboring 9 NCCN biomarkers, liquid CGP increases detection in patients with limited tissue results, but does not increase detection in patients with tissue CGP results available. In contrast, tissue CGP can add meaningfully to liquid CGP for detection of NCCN biomarkers and should be considered as a follow-up when an oncogenic driver is not identified by liquid biopsy.

Racial Differences in Patient-Reported Symptoms and Adherence to Adjuvant Endocrine Therapy Among Women With Early-Stage, Hormone Receptor-Positive Breast Cancer

IMPORTANCE

Adjuvant endocrine therapy (AET) reduces breast cancer recurrence, but symptom burden is a key barrier to adherence. Black women have lower AET adherence and worse health outcomes than White women.

OBJECTIVE

To investigate the association between symptom burden and AET adherence differences by race.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study using electronic health records with patient-reported data from a large cancer center in the US. Patients included Black and White women initiating AET therapy for early-stage breast cancer from August 2007 to December 2015 who were followed for 1 year from AET initiation. Sixty symptoms classified into 7 physical and 2 psychological symptom clusters were evaluated. For each cluster, the number of symptoms with moderate severity at baseline, and symptoms with 3-point or greater increases during AET were counted. Adherence was measured as the proportion of days covered by AET during the first-year follow-up. Multivariable regressions for patients' adherence adjusting for race, symptom measures, sociodemographic characteristics, and clinical characteristics were conducted. Kitagawa-Blinder-Oaxaca decomposition was used to quantify racial differences in adherence explained by symptoms and patient characteristics. Analyses were conducted from July 2021 to January 2022.

EXPOSURES

Physical and psychological symptoms at baseline and changes during AET.

RESULTS

Among 559 patients (168 [30.1%] Black and 391 [69.9%] White; mean [SD] age 65.5 [12.1] years), Black women received diagnoses younger (mean [SD] age at diagnosis, 58.7 [13.7] vs 68.5 [10.0] years old) than White women, with more advanced stages (30 Black participants [17.9%] vs 31 White participants [7.9%] had stage III disease at diagnosis), and lived in areas with fewer adults attaining high school education (mean [SD], 78.8% [7.8%] vs 84.0% [9.3%]). AET adherence in the first year was 78.8% for Black and 82.3% for White women. Black women reported higher severity in most symptom clusters than White women. Neuropsychological, vasomotor, musculoskeletal, cardiorespiratory, distress, and despair symptoms at baseline and increases during the follow-up were associated with 1.2 to 2.6 percentage points decreases in adherence, which corresponds to 4 to 9 missed days receiving AET in the first year. After adjusting for psychological symptoms, being Black was associated with 6.5 percentage points higher adherence than being White.

CONCLUSIONS AND RELEVANCE

In this cohort study, severe symptoms were associated with lower AET adherence. Black women had lower adherence rates that were explained by their higher symptom burden and baseline characteristics. These findings suggest that better symptom management with a focus on psychological symptoms could improve AET adherence and reduce racial disparities in cancer outcomes.

Evolution of biomarker testing in advanced non-small cell lung cancer (aNSCLC) and metastatic breast cancer (mBC) in U.S. community practices

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Background: Biomarker testing has advanced from single-gene to NGS. This study examined aNSCLC and mBC biomarker testing ≤ 90d of advanced (adv) or metastatic (met) diagnosis (Dx) and treatment (tx) patterns at US practices. Methods: A retrospective observational study used Flatiron Health electronic health-record-derived de-identified database at OneOncology (OO) community and non-OO Flatiron Health nationwide (NAT) sites (̃90% community, ̃10% academic). Patients (Pts) ≥ 18y, with Dx of aNSCLC or mBC from 1/1/18 - 4/30/21, with ≥ 1 visit ≤ 90d after adv/met Dx and ≥ 90d follow-up were evaluated. Descriptive analyses and logistic regression were used. Results: A total of 16,882 pts with aNSCLC (2366 OO; 14,516 NAT), and 6500 pts with mBC (1026 OO; 5474 NAT) were included. Overall testing was high and stable (OO: 85% aNSCLC, 98% mBC; NAT: 84%, 97%) with higher NGS testing at OO (58% aNSCLC; 28% mBC) vs NAT (49%; 16%) (Table), which reflected more pts with aNSCLC tested for all 6 mutations (ALK, BRAF, KRAS, ROS-1, EGFR, PD-L1; 54% OO vs 50% NAT, p<0.001) and more pts with mBC tested for PIK3CA (27% OO vs 16% NAT, p<0.001). In aNSCLC, NGS testing increased similarly for OO and NAT over time (p>0.05); mBC NGS testing increased faster at NAT vs OO (p<0.05). Of pts tested and treated, 16% aNSCLC (1945 OO; 11,376 NAT) and < 3% mBC (14 OO; 108 NAT) received tx before test results were available. For pts with aNSCLC with ≥ 1 actionable mutation (ALK, BRAF, ROS-1, EGFR), 18% OO and 22% NAT had tx before test results. Cancer immunotherapy plus chemotherapy was the most common tx (36 % OO vs 40 % NAT); after test results, 33% vs 56% OO and 45% vs 44% NAT pts stayed on tx vs switched to targeted tx. For pts with aNSCLC with ≥ 1 aforementioned actionable mutations who waited until test results were available, 65% received targeted tx at OO and NAT. Conclusions: Biomarker testing has become standard of care in aNSCLC and mBC in US community settings. NGS rates increased over time and were higher at OO vs NAT. Differences in pts treated before test results reflects the need to wait for NGS results to inform initial tx in aNSCLC vs non-NGS results for mBC. This study shows NGS testing in US community practices has increased since 2018, particularly in mBC, but opportunities remain to optimize NGS results into tx decisions.[Table: see text]

Race differences in patient-reported symptoms and adherence to adjuvant endocrine therapy among women with early-stage, hormone receptor-positive breast cancer

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Background: Low rates of adherence to adjuvant endocrine therapy (AET) is a significant clinical problem. Symptom burden is a key barrier to adherence, but less is known about how changes in symptom burden affects adherence. Moreover, whether higher symptom burden in racial minorities explains their lower rates of adherence, has been relatively unexamined. We used longitudinal data to address these gaps in knowledge. Methods: Using electronic medical records linked with patient-reported data, Medicare and Medicaid claims, we identified women with early-stage, hormone receptor-positive breast cancer who initiated AET from a large cancer center in 08/2007-12/2015, had continuous insurance coverage and ≥1 symptom report before and during AET. Patient-reported symptoms were collected using a tablet-based platform [ConcertAI]. A total of 49 physical symptoms and 11 mental health symptoms were evaluated and classified into 7 physical and 2 mental clusters based on previous literature and clinical expertise. For each cluster, we counted the number of symptoms with moderate severity (≥3 points) at baseline, and with ≥3-point increase during 1-year follow-up. Adherence was defined as the percent of days covered by AET during the 1-year follow-up. We compared Black and White patients’ symptoms at baseline and changes during the therapy, and conducted multivariable regression for patients’ adherence adjusting for race, symptom measures, sociodemographic and clinical characteristics. Results: Black women (n = 168) were diagnosed at a younger age, with more advanced stage, and lived in areas with lower socioeconomic status than White women (n = 391, p<.05). Adherence to AET in the first year was 78.8% for Black and 82.3% for White women ( p=.16). Black women experienced higher severity in most symptom clusters at baseline and during the follow-up than White women ( p<.05). Neuropsychologic, Vasomotor, Musculoskeletal, Cardiorespiratory, Distress and Despair symptom clusters both at baseline and their increases during the follow-up were associated with 1.2 to 2.6 percentage points (ppt, p<.05) decreases in adherence. This means, each additional count of moderate severity symptoms in these clusters would decrease 4 to 9 days on AET. After adjusting for distress and despair symptoms, Black women had a 6.5 ppt higher adherence rate than White ( p<.05). Conclusions: Black women had higher symptom burden at baseline and during the first year of AET. Both physical and mental health symptoms at baseline and the changes during therapy were associated with lower adherence. However, Black women had non-significantly lower rates of adherence despite the higher symptom burden due to unmeasured factors that offset the impact of symptom severity. Better symptom management could improve AET adherence and potentially reduce racial disparities in cancer outcomes.

Biomarker testing patterns and actionability in advanced non-small cell lung cancer (aNSCLC) at OneOncology (OneOnc)

287

Background: Recent approvals of targeted treatments (tx) have improved personalized care in aNSCLC. Biomarker testing is crucial for patients (pts) to receive optimal tx expeditiously. This study examined aNSCLC biomarker testing and tx patterns at OneOnc. Methods: Pts diagnosed with aNSCLC (stage ≥ IIIb) from 1/1/2015 to 5/31/2020, aged ≥ 18 years, and with ≥ 1 visit ≤ 90 days of advanced (Adv) diagnosis (Dx) were retrospectively evaluated using the nationwide Flatiron Health electronic health record derived de-identified database from selected OneOnc sites. Descriptive analyses were conducted to evaluate testing patterns for ALK, BRAF, EGFR, KRAS, PD-L1, and ROS-1 biomarkers and actionable mutation tx pattern. Results: Overall 3,860 aNSCLC pts were included, median age was 69 years, 47% females, 66% non-squamous, 29% squamous, 4% histology NOS, and 23% with ECOG performance status 0-1. Of the 3,152 (82%) pts tested for any biomarker, 64% received next-generation sequencing (NGS) vs. 36% received other biomarker tests only. Testing rates varied by biomarker: EGFR (74%), ALK (72%), ROS-1 (66%), PD-L1 (57%), BRAF (56%), KRAS (54%). Pts who received all 6 biomarker tests increased from 12% (2015), 23% (2016), 40% (2017), 41% (2018), 48% (2019) to 56% (2020). Among the tested pts, the median time from Adv Dx to the first test result was 20 days (d) and from specimen collection after Adv Dx to the first test result was 12 d. Pts tested and treated before test result available declined from 28% (2015) to 16% (2020). Of 1,207 pts with actionable mutations, 390 (32%) received tx before the test result: 35% chemotherapy (chemo) only, 28% chemo + cancer immunotherapy (CIT), and 15% CIT only. After the test result, 26% to 81% of pts received no or other tx not specific to actionable mutations [Table]. Conclusions: Findings from this study demonstrated an increase in aNSCLC biomarker testing at OneOnc over time, while 44% pts in 2020 did not receive testing on all 6 biomarkers. Some pts had tx prior to the test result, but this trend appeared to decline. Further studies are warranted to better understand the reasons for pts receiving tx that were not specific to their actionable mutations.[Table: see text]

NGS testing patterns in advanced non-small cell lung cancer (aNSCLC) and metastatic breast cancer (mBC): OneOncology (OO) sites compared to Flatiron Health Nationwide (NAT)

288

Background: Personalized treatment (tx) decisions can be improved through diagnostic tests with NGS by detecting different actionable mutations. OO, a research-focused network of community practices, has a network-wide precision oncology initiative and has advocated for NGS testing in advanced cancers since 2019. This study evaluated NGS testing patterns in aNSCLC and mBC populations descriptively in OO community sites and Flatiron Health NAT. Methods: This study used the Flatiron Health EHR derived de-identified database from [1] four OO sites, and [2] NAT. Patients (pts) diagnosed (Dx) with aNSCLC (stage ≥ IIIb) or mBC from 1/1/2015 to 5/31/2020, aged ≥ 18 years, had ≥ 1 visit ≤ 90 days (d) of advanced or metastatic Dx, and had ≥ 1 biomarker test were included. NAT NGS was confirmed via abstraction from patient records. Descriptive analyses were conducted to assess NGS testing patterns and pts characteristics by tumor type. Results: Of biomarker tested pts at OO vs. NAT (community:academic: 90%:10% aNSCLC; 93%:7% mBC), 2,029 of 3,152 (64%) OO vs. 13,681 of 29,572 (46%) NAT in aNSCLC and 514 of 1,282 (40%) OO vs. 2,458 of 12,175 (20%) NAT in mBC received NGS ± other tests. Testing rate of all 5 aNSCLC biomarkers (ALK, BRAF, EGFR, ROS-1, and KRAS) was higher with NGS vs. other tests for OO (87% vs. 6%) and NAT (87% vs. 11%). In mBC, a higher testing rate of BRCA with NGS vs. other tests (OO: 68% vs. 26%, NAT: 71% vs. 28%) and similar testing rate on HER2 (OO: 98% vs. 98%, NAT: 100% vs. 99%). Median time from Dx to NGS test result at OO vs. NAT was 33 d vs. 32 d in aNSCLC and 70 d vs. 188 d in mBC. NGS testing rates increased over time, with higher rates at OO vs. NAT [Table]. Pts with NGS vs. other tests were slightly younger in aNSCLC (OO: 68 y vs. 70 y, p = 0.001; NAT: 69 y vs. 70 yr, p < 0.001) and mBC (OO: 61 y vs. 67 y, p < 0.001; NAT: 61 y vs. 66 y, p < 0.001), and slightly more commercially insured in aNSCLC (OO: 48% vs. 45%, p = 0.3; NAT: 37% vs. 33%, p < 0.001) and mBC (OO: 54% vs. 48% OO, p = 0.053; NAT: 42 % vs. 36 %, p < 0.001). Conclusions: The adoption of NGS differed by cancer type and NGS testing rates have increased over time in aNSCLC and mBC. While some pts may have received testing outside of the Flatiron network, OO had a higher NGS uptake than NAT, and had a shorter time to testing in mBC that was possibly related to a network wide strategy recommending testing at Dx of advanced disease. Future studies on tx pattern after NGS testing are warranted to improve the actionability of NGS to foster personalized tx. [Table: see text]

Healthcare resource utilization and cost among patients treated for early-stage triple-negative breast cancer

Background: This retrospective, observational study examined real-world healthcare resource utilization (HCRU) and costs in 308 patients diagnosed with early-stage (II-IIIB) triple-negative breast cancer between 1 March 2008 and 31 March 2016. Methods: HCRU and costs were evaluated for two time periods: from neoadjuvant treatment start date to surgery (Time 1) and after surgery to recurrence or death (Time 2). Results: The sample included 236 patients who received neoadjuvant treatment without subsequent adjuvant treatment (Neo) and 72 patients who received neoadjuvant treatment followed by adjuvant treatment (Neo + adj). Mean monthly HCRU events and mean monthly costs per patient were higher in Time 1 compared with Time 2 for both groups. Conclusion: These results demonstrate the economic burden of early-stage triple-negative breast cancer especially during neoadjuvant treatment phase.

Real-world treatment patterns and effectiveness outcomes in patients with early-stage triple-negative breast cancer

Background: This retrospective, observational study examined real-world treatment patterns and effectiveness outcomes in 450 patients with stage II-IIIB early-stage triple-negative breast cancer treated in the community oncology setting. Methods: Kaplan-Meier methods were used to evaluate event-free survival (EFS), time to recurrence and overall survival (OS). Cox regression models were used to evaluate predictors of EFS and OS by pathological complete response (pCR) status. Results: Among patients receiving neoadjuvant systemic therapy only, pCR was a predictor of EFS and OS. Conclusion: These results highlight the unmet need for therapies that improve outcomes for patients with early-stage triple-negative breast cancer including increasing rates of pCR among patients receiving neoadjuvant therapy.

Differences by race in patient-reported symptoms during chemotherapy among women with early-stage, hormone receptor-positive breast cancer

6528

Background: Symptom burden may contribute to racial differences in cancer treatment adherence and survival. Evidence on changes in symptom burden during chemotherapy and whether these differ by race is scarce. We used patient reported outcomes data collected before and after breast cancer chemotherapy initiation to compare symptom burden by race. Methods: Using electronic medical records of a large cancer center in the southern region of the US, we identified Black and White women diagnosed with stage I-III, hormone-receptor positive breast cancer from January 2007 to December 2015. A tablet-based platform [ConcertAI] was used to collect patient reported symptoms at the point of care. We included patients with at least one completed symptom report before and during chemotherapy. We focused on two standardized composite scores – physical symptoms and treatment side-effect (mean of 50 and standard deviation of 10), and calculated changes in symptoms using the closest report before chemotherapy and the most severe score reported during chemotherapy. Patients with a 10-point increase were classified as having a clinically meaningful increase in symptom burden. We used Oaxaca-Blinder decomposition to quantify racial differences in symptom burden change explained by baseline characteristics. These included baseline symptom scores, sociodemographic characteristics (age, regional level household income and education, state) and clinical characteristics (cancer stage and primary chemo regimen). Results: Among 1,167 included patients, Black women (30%) were younger (52 vs. 55 years old, p<.001), more likely to live in areas with lower median household income and less education, and reported most severe scores about 2 weeks later than White women ( p<.05). They were also more likely to report a 10-point increase in symptom burden for physical (68.5% vs. 61.2%, p=.017) and side-effects symptoms score (49.0% vs. 41.4%, p=.015). This was driven by larger increases in selected individual symptoms among Black women, such as sweating, itching, and numbness (under physical symptom score), and hair loss and taste change (under side-effect score). Decomposition analyses showed that baseline characteristics (especially primary chemo regimen) explained 79.2% ( p=.002) and 35.2% ( p=.131) of the increased probability of Black women reporting a 10-point increase in physical symptom and side-effects scores respectively. Conclusions: Black women with early-stage breast cancer were more likely to report a clinically meaningful increase in treatment side-effects and physical symptoms during chemotherapy compared to White women. Differences by race in physical symptoms scores were mostly explained by baseline characteristics. Future studies should examine whether racial differences in symptom burden translate into differences in treatment adherence and mortality.

A study evaluating targeted therapies in participants who have advanced solid tumors with genomic alterations or protein expression patterns predictive of response (MyTACTIC)

TPS1588

Background: Cancer treatment is evolving toward a more personalized approach in which the intersection of genomics, pathology and imaging methods leads to individualized care. Furthermore, identification of novel genomic alterations and other biomarkers has the potential to lead to customized, targeted treatments. Matching specific therapies to tumor biomarkers has the potential to yield valuable clinical information. Here we present a multiarm basket trial that matches patients with a broad array of metastatic solid cancers to investigational therapies alone or in combination based on specific, targetable genomic alterations or protein expression patterns that are potentially predictive of response (MyTACTIC). Historically, such trials have been conducted at large academic medical centers rather than community centers, where most US patients with cancer receive treatment. Prioritizing community centers for this study presents an exciting opportunity to generate data from a more representative patient population. Methods: This phase II, multicenter, nonrandomized, open-label study is enrolling approximately 200 participants with advanced solid tumors that harbor alterations including mutations, fusions, amplifications and protein loss in specific biomarkers that include human epidermal growth factor receptor 2 (HER2), phosphoinositide 3-kinase (PI3K), anaplastic lymphoma kinase (ALK), proto-oncogene tyrosine-protein kinase (ROS1), protein kinase B (AKT), phosphatase and tensin homolog (PTEN), high tumor mutational burden (TMB), high microsatellite instability (MSI) and deficient mismatch repair (dMMR). Patients aged ≥18 years with positive local biomarker results from tissue or blood samples will be enrolled from community oncology centers and practices. Eligibility criteria have been broadened to allow enrollment of a diverse population of patients, including those with nonmeasurable disease, HIV or viral hepatitis infections, and to allow for previous treatment with anticancer agents in the same class. Once general and arm-specific criteria are met, patients will be assigned to 1 of 10 treatment arms to receive mono- or combination therapy with targeted agents, immunotherapy and/or chemotherapy (≤25 patients per arm). The primary objective is to evaluate confirmed objective response rate, as assessed by the investigator according to RECIST version 1.1 or RANO criteria for primary central nervous system tumors. Progression-free survival, duration of response, overall survival and safety will also be assessed. Special attention has been paid to the study design and implementation to ensure equitable access, along with flexibility to add additional baskets. Enrollment is ongoing. Clinical trial information: NCT04632992.

Impact of clinical trial enrollment on episode costs in the Oncology Care Model (OCM)

6513

Background: Clinical trials are critical for improving outcomes for patients with cancer. However, there is some concern from health insurers that clinical trial participation can increase total cost of care for cancer patients. We investigated the impact of clinical trial participation on total costs paid by Medicare during the OCM program in a large community-based practice. Methods: Tennessee Oncology (TO) is a community oncology practice comprising over 90 oncologists across 30 sites of care. We linked TO trial data and electronic medical record data with OCM data for episodes of care from 2016-2018. To assess the impact of trial participation on total cost relative to routine care, we created matched comparator groups for each OCM episode based on cancer type, metastatic status, number of comorbidities, performance status, and age. Patients with breast cancer receiving hormone therapy only were excluded. Absolute and percent cost differences between groups were calculated for episodes that had a comparator group size of five or greater. Differences in total cost for trial episodes were compared to non-trial episodes, and significance was assessed using the Mann–Whitney U test. We also studied the impact of trial participation on receipt of active treatment in the last 14 days of life (TxEOL), hospice use, and hospitalizations. Results: During the study period, 8,026 completed OCM episodes met study criteria. Patients were enrolled in a clinical trial for 459 of these episodes. On average, episodes during which patients were on trial cost $5,973 less than matched non-trial episodes (Table), independent of early versus late-phase trial. Most savings resulted from decreased drug costs. There were no differences in rates of TxEOL (15% vs. 14% p=1.0), rates of hospitalizations (31% vs. 30% p=0.54), or hospice use (52% vs. 62% p=0.08) between trial and non-trial episodes. Median difference from comparator group average cost was significantly lower for clinical trial episodes (-18% vs. -6%, p<0.01). Conclusions: In the community setting, total costs paid by Medicare for patients participating in clinical trials during OCM episodes were lower than costs for similar patients receiving routine care. Clinical trial participation did not adversely impact end-of-life care or likelihood of hospitalization. These findings suggest that patient participation in clinical trials does not increase total cost of care nor enhance financial risk to payers.[Table: see text]

Estimates of stage-specific preclinical sojourn time across 21 cancer types

e18584

Background: Cancer progression rates following diagnosis are readily measured. However, the progression rate of cancer during the preclinical sojourn time is generally unobserved. Understanding the duration of preclinical stages (“dwell time”) would allow clinicians to better identify appropriate screening intervals for cancer. We therefore elicited estimates of progression rate during the preclinical sojourn time for a wide variety of malignancies from a panel of clinical experts. Methods: We used a validated consensus methodology (RAND/UCLA modified Delphi panel method) to elicit per-stage dwell time estimates for 20 solid cancers and lymphoma from experts. Eleven experienced oncologists (general and subspecialists) from community and academic centers reviewed literature on the natural history of disease and estimated in number of years (<1 to 9+ years) how long it would take each cancer to progress from the beginning of clinically detectable Stage I/II/III to the beginning of the next stage in untreated adults. Cancer histological subtypes were grouped and experts were asked to provide an overall rating. Ratings were completed before and after a discussion of areas of disagreement. Results: Expert estimates and range of dwell time for 21 cancer types are provided in Table. Prostate and thyroid cancer were estimated to be the slowest growing, taking approximately 7 and 5 years respectively to progress through Stage I (range 4-8), 5 years to progress through Stage II (range 3-7), and 3 and 4 (range 2-5) years respectively to progress through Stage III. Esophageal, lung, liver/intrahepatic bile-duct, gallbladder, and pancreatic cancers were estimated to progress quickly through all three stages (1-2 years per stage). Conclusions: These findings summarize practicing oncologists’ estimates of dwell time in preclinical disease. Experts agreed on dwell times although ranges were large and differences in cancer subtypes were not captured. Generally, estimates trend with published data on survival with treatment: cancers with higher survival (e.g., prostate, thyroid) were estimated to grow slower, while cancers with lower survival (e.g., pancreatic, liver/intrahepatic bile-duct, gallbladder) were estimated to grow faster. These estimates could be useful when determining screening intervals for these or any subset of these cancers. [Table: see text]

The impact of cancer-related diarrhea on changes in cancer therapy patterns

12111

Background: We studied the impact that cancer related diarrhea (CRD) has on cancer therapy and treatment patterns, including persistence, discontinuation, adherence, and switching of chemotherapy and targeted therapies in patients with and without CRD. Methods: We performed a longitudinal observational study among adult ( > 18 yrs) patients with CRD identified by diagnosis codes or pharmacy claims compared to matched (1:1) non-CRD patients using claims data derived from the IQVIA PharMetrics Plus database. Index date was defined as the date of the first cancer claim, and we re-indexed patients based on CRD claims. Each patient had a 6-month pre-index period and a minimum 3-month follow-up post-index period. To adjust for selection bias and baseline differences, we directly matched the CRD patients to non-CRD patients. Treatment patterns were evaluated and stratified for the first cancer therapy with or without CRD (chemotherapy vs targeted therapy vs both targeted and chemotherapy). Discontinuation was defined as a 30-day gap for chemotherapy and a 14-day gap for targeted therapies from index therapy; switching was a new chemotherapy or targeted therapy prescription within 30 days following discontinuation of index therapy. We computed adherence as the proportion of days covered over the 12-month post-index period and persistence as mean number of days on index therapy. A Cox proportional hazards model was used to estimate the difference in risk of discontinuation of index therapy between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer; each group further grouped by those receiving either chemotherapy (n = 47,220), targeted therapy (n = 2,427), or both treatments (n = 5,313). Patients with CRD discontinued the index therapy more frequently than non-CRD patients for chemotherapy (81.5% vs 62.3%), targeted therapy (69.2% vs 64.3%) or both (96.0% vs 85.5%) (p < 0.0001). Also, the overall percentage of discontinuation (82.4% vs. 64.6%) was significantly higher among patients with CRD. The mean time to discontinuation (59.6±54.1 vs. 68.3±76.6 days) was significantly lower (p < 0.0001) in patients with CRD. The mean time to switch (72.0±48.6 vs. 96.9±84.0 days), mean persistence (95.1±98.1 vs. 154.3±142.7 days), and mean adherence (25.5%±37.2 vs. 47.9±41%) were significantly lower (all p < 0.0001) among patients with CRD compared to non-CRD. The percentage of patients requiring a dose titration for their index cancer therapy was significantly higher (21.8%) for the CRD cohort versus 8.5% for non-CRD patients (p < 0.0001). Conclusions: Patients with CRD were 40% (adjusted) more likely to discontinue the index therapy than patients without CRD. The persistence of index cancer therapy and time to switch were also lower for patients with CRD. Strategies to control CRD and continue cancer therapy are urgently needed.

Perspectives on under-representation of minority patients (pts) in clinical trials

e18521

Background: About 40% of the US population are from minority groups. Minority pts are under-represented in oncology clinical trials, which limits the applicability of results to the general population and perpetuates poor relationships between healthcare systems and minority communities. This assessment investigated underlying causes of this lack of minority representation in clinical trials and proposes plans to promote diversity. Methods: To better understand the limited inclusion of under-represented pts in oncology clinical trials, 10 specialists in cancer care were selected to provide their perspectives. Specialists were chosen because of their experience enrolling minority pts in clinical trials and met virtually in Dec 2020 via Within3, a secure digital communication platform, to discuss obstacles faced in recruiting minority pts and potential strategies to address these concerns. Specificity and alignment in responses were achieved through software analytics and follow-up queries. Results: The 10 specialists identified as Asian (10%), Black (30%), White (50%), and Hispanic (10%), and began practicing medicine in the 1980s-2010s. All are involved in clinical research and treat a range of minority pts in both urban and suburban settings. Most specialists (8/10) reported treating > 20 minority pts with cancer annually. However, few specialists (2/10) reported that > 20% of their minority pts have enrolled in clinical trials. Specialists agreed that minority pts experience barriers to participation in clinical research, including lack of trust in the healthcare system, materials in their native languages, financial support, minority investigators involved in clinical trials, and accessible study sites. The specialists proposed strategies that could be implemented to increase minority enrollment. These included study sites where minority populations live and industry funded outreach and educational efforts in minority communities. If sites are more accessible, this can reduce time and financial pressures associated with study participation. The specialists recommended that studies be designed to be more supportive of minority populations, specifically regarding inclusion and exclusion criteria and reimbursement of costs. They also advised that increased diversity among clinical researchers and allied personnel may increase the ability of the clinical team to connect with pts and assist in building trust in their communities. Finally, they emphasized the importance of providing informed consent forms and study materials in pts’ native languages. Conclusions: While challenges exist to increasing diversity in oncology clinical studies, a broad consortium of clinical specialists agreed that they can be addressed by community outreach and education, making study sites more accessible, availability of study materials in pts’ native languages, and improving diversity of clinical teams.

Characterizing unplanned resource utilization associated with cancer-related diarrhea

e18625

Background: In clinical oncology practice, diarrhea is a very common and severe side effect of cancer treatments including from radiotherapy, chemotherapy, and targeted therapies. Cancer-related diarrhea (CRD) leads to increased healthcare resource consumption due to unscheduled outpatient visits, and , increased hospital stays requiring intensive supportive care measures. We evaluated CRD patients receiving chemotherapy, targeted therapy, or both, requiring emergency department (ED), physician office visits, hospitalizations, and length of stay (LOS) compared to a matched cohort of non-CRD patients. Methods: We performed a longitudinal study among adult patients ( > 18 yrs) with CRD identified by diagnosis codes or pharmacy claims compared to matched non-CRD patients using claims data derived from the IQVIA PharMetrics Plus database. Index date was the first cancer claim date and patients were re-indexed based on their CRD claim. Each patient had a 6-month pre-index period, a minimum 3-month post-index period and had ≥12 months of continuous enrollment following the CRD index date. To adjust for selection bias and baseline differences, we matched CRD patients to non-CRD patients (1:1) by age, gender, geography and payer type. Patients were stratified by cancer therapy type (chemotherapy, targeted therapy or both treatments). We reported proportion of patients with hospitalizations, average length of stay (LOS), and ED visits. A generalized estimating equation model with log link and binomial distribution adjusted for type of cancer, therapy, and Charlson Comorbidity Index (CCI) was built to estimate the difference in occurrence of hospitalization between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer with 12-month continuous enrollment. The proportion of patients with ED visits (36.2% vs 18.9%, p < 0.0001) and hospitalizations (29.6% vs 12.8%, p < 0.0001) were significantly higher among CRD versus non-CRD cohort. When compared to non-CRD patients, CRD patients were more likely to be hospitalized (adjusted OR 2.28. 95% CI of 2.23-2.33). Mean CRD-specific office/hospital visits were significantly higher in the CRD cohort compared to the non-CRD cohort over the 12-month post-index period and patients had more CRD-specific visits to ED (7.5% vs 1.8%); physician’s offices (14.7% vs 3.8%); laboratory testing (11.6% vs 3.2%) and outpatient ancillary services (10.9% vs 2.6%) (all p < 0.0001). Mean hospital LOS among patients with CRD was higher than non-CRD patients (6.6±8.9 vs 5.8±10.5 days, p < 0.0001). Conclusions: Patients with CRD used significantly more resources, including outpatient services, ED visits, and hospitalizations. Effective prevention of CRD remains an unmet strategy to reduce the overall cost of cancer care.

Healthcare utilization and costs associated with cancer-related diarrhea

e18623

Background: Diarrhea is a common toxicity of cancer treatments, including radiotherapy, chemotherapy, and/or targeted therapies. Cancer-related diarrhea (CRD) leads to increased healthcare utilization and cost. This study evaluated the all-cause and CRD-specific healthcare utilization and cost of patients with CRD compared to a matched non-CRD cohort. Methods: We conducted a longitudinal observational study among adult patients ( > 18 years) with CRD using diagnosis codes or pharmacy claims compared to matched non-CRD patients using claims data from the IQVIA PharMetrics Plus database (October 2015 to March 2020). The index date was the date of the first cancer claim, and we re-indexed patients based on their CRD claim. Each patient had a 6-month pre-index period and a minimum 3-month post-index period. Patients were also required to have ≥12 months of continuous enrollment following the CRD index date. We directly matched patients 1:1 from the CRD cohort to the non-CRD cohort to adjust for selection bias and baseline differences. Our aim was to compare all-cause healthcare costs over a fixed 12-month post-index period, converting all costs to 2020 USD using the Consumer Price Index's medical component. We analyzed healthcare utilization for CRD-treated, CRD-inadequately treated, and CRD-untreated sub-cohorts (per Buono et al., J Econ 2017). Secondary endpoints included healthcare cost (proportion of patients, per-patient mean and median) and healthcare utilization (prescription fills and visits to the emergency department [ED], physician office, lab/pathology and outpatient ancillary services). We built one generalized estimating equation model with log link and gamma distribution adjusted for type of cancer, therapy and Charlson Comorbidity Index (CCI) to estimate the difference in total healthcare cost between CRD and non-CRD cohorts. Results: We evaluated a total of 104,135 matched pairs of CRD and non-CRD adult patients with solid or hematologic cancer receiving either targeted or chemotherapy, with 12-month continuous enrollment. Patients with CRD incurred significantly higher mean ($104,880 vs $39,664, p < 0.0001) and median ($59,969 vs $8,914, p < 0.0001) all-cause healthcare cost compared to patients without CRD over the 12-month post-index period. Inadequately treated CRD patients had the mean highest cost ($129,531) vs adequately CRD-treated ($107,050) or untreated CRD patients ($56,350) (all p < 0.0001). Mean pharmacy cost for CRD and non-CRD patients were ($35,190 vs $15,883); visits to the ED ($1,107 vs $431), physician office ($3,457 vs $2,058), lab/pathology ($4,074 vs $1,404), and outpatient ancillary services ($15,805 vs $4,940) (all p-values < 0.0001). Conclusions: Our findings show that patients with CRD had nearly 2.9 times higher all-cause total cost than patients without CRD after adjusting for covariates. Prevention of CRD may result in a significant reduction in cancer-treatment cost.

Efficacy of enobosarm, a selective androgen receptor (AR) targeting agent, correlates with the degree of AR positivity in advanced AR+/estrogen receptor (ER)+ breast cancer in an international phase 2 clinical study

1020

Background: The AR is expressed in up to 90% of ER+ breast cancer where it acts as a tumor suppressor. Historically, therapy with synthetic androgens had efficacy, but virilizing side effects and toxicity limited their use. Enobosarm is a selective AR activating agent that does not cause masculinization and has positive attributes such as promotion of bone and improvement of physical function. In a phase 2 study, correlation between the degree of AR staining and antitumor activity in AR+/ER+ patients with metastatic breast cancer (MBC) was examined. Methods: A phase 2, open label, parallel design randomized study was conducted in 136 patients to evaluate the efficacy and safety of enobosarm in heavily pretreated women with AR+/ER+ MBC. Patients were randomized to 9 mg (n=72) or 18 mg (n=64) of oral daily enobosarm. AR expression (%AR nuclei staining) in breast cancer samples was determined centrally by immunohistochemistry. The correlation between %AR staining and clinical outcomes was examined with a focus on the 9mg dose, selected for the phase 3 study and the optimal %AR staining established. Results: Tumor objective outcomes correlated with percent AR staining (Table). Further, using a 40% AR staining cutoff in patients with measurable disease, the clinical benefit rate (CBR) for ≥40% AR is 80% and <40% is 18% (p<0.0001). Best objective tumor response (BOR) in patients with ≥40% AR is 48% and <40% is 0% (p<0.0001). At ≥40% AR, median radiographic progression free survival (rPFS) is 5.47 and mean is 7.15 months vs <40% AR where the median rPFS is 2.72 and mean is 2.7 months. Similar %AR staining correlation was observed in the 18mg cohort. Enobosarm treatment was well tolerated with significant positive effects on quality of life measurements. Conclusions: Enobosarm is a novel oral selective AR activating agent in which a higher % AR staining correlates with a greater antitumor activity. By targeting and activating AR, enobosarm may represent a new hormone treatment approach for AR+/ER+ MBC. The phase 3, ARTEST trial will commence in early 2021 and randomize patients with AR+/ER+/HER2- heavily treated MBC that have progressed on a non-steroidal aromatase inhibitor, fulvestrant and CDK 4/6 inhibitor to receive enobosarm or standard endocrine therapy. Clinical trial information: NCT02463032 .[Table: see text]

Olaparib in hormone receptor-positive, HER2-negative metastatic breast cancer with a somatic BRCA2 mutation

The oral poly(adenosine diphosphate-ribose) polymerase inhibitor olaparib is approved for the treatment of patients with human epidermal growth factor 2-negative (HER2-) metastatic breast cancer (mBC) and a germline breast cancer susceptibility gene (BRCA) mutation who have been treated with chemotherapy. This case report describes a 63-year-old postmenopausal woman with somatic BRCA2-mutated mBC who responded to olaparib treatment following multiple prior lines of therapy. The patient presented in January 2012 with locally advanced, hormone receptor-positive (HR+), HER2- BC which, despite initial response to neoadjuvant chemotherapy, recurred as bone disease in February 2014, and subsequently skin (June 2016) and liver (October 2016) metastases. A comprehensive 592-gene next-generation sequencing panel (Caris Life Sciences), performed on a skin biopsy, detected a pathogenic frameshift mutation in BRCA2 (H3154fs, c.9460delC), which was not identified in a 28-gene hereditary cancer germline analysis (Myriad Genetics, Inc.), and was therefore considered to be a somatic mutation. In January 2017, cell-free DNA (cfDNA) analysis (Guardant Health, Inc.) confirmed the BRCA2 H3154fs mutation in plasma. After several lines of chemotherapy and endocrine therapy, deriving clinical benefit from eribulin and capecitabine, the disease progressed by October 2017, and olaparib (300 mg orally twice daily) was initiated in January 2018. By April 2018, the liver lesions had shrunk by 80% and a >90% response in multiple skin lesions was noted. Clinical response was maintained for 8 months, followed by progression in the skin in September 2018. Biopsy of recurrent lesions revealed a novel BRCA2 mutation, E3152del (c.9455_9457delAGG), predicted to restore the open reading frame and presumably the mechanism of resistance to olaparib. Further likely resistance mutations were noted in subsequent cfDNA analyses. This case demonstrated a clinical response with olaparib as a later-line therapy for HR+, HER2- mBC with a somatic BRCA2 mutation.

Expert Insights on Triple-Negative Breast Cancer: Preparing for the Next Wave of Treatments

Heather R. Greene, MSN, FNP, AOCNP®, and Lee S. Schwartzberg, MD, FACP, discussed the current and future treatment landscape for triple-negative breast cancer, including recent and emerging data on approved treatments, novel therapeutic options being investigated, and best practices for identifying and monitoring adverse events associated with PARP and immune checkpoint inhibitors at JADPRO Live 2019.

Abstract PS13-42: Locoregional recurrence in patients with early-stage triple-negative breast cancer receiving neoadjuvant systemic therapy: Patient characteristics and clinical outcomes

Background: Recurrence is common among patients with early-stage triple-negative breast cancer (ESTNBC). There is minimal real-world evidence describing the patient characteristics and clinical outcomes following recurrence among patients receiving neoadjuvant chemotherapy for ESTNBC. Methods: This retrospective, observational study aimed to describe the demographic and clinical characteristics and clinical outcomes in ESTNBC patients experiencing locoregional recurrence in the US community oncology setting in the Concerto HealthAI Definitive Oncology Dataset. Eligibility criteria included female sex, age 18+ years, diagnosis of stage II, IIIA or IIIB ESTNBC between 3/2008 and 3/2016, and receipt of definitive surgical resection following neoadjuvant systemic therapy. Descriptive methods were used to evaluate patient characteristics and treatment patterns in this population. Locoregional recurrence was defined as recurrence in the same breast and/or regional nodal recurrence as documented by the provider in the medical record. Results: Of 308 patients who received neoadjuvant treatment for ESTNBC, 27.3% patients (n=84) observed recurrence, within which 25.0% (n=21) were locoregional and 75.0% (n=63) were metastatic. All 21 patients with locoregional recurrence were 65 or younger, with mean age of 50.6 (SD 8.7) at initial diagnosis. They were primarily White (47.6%, n=10) or African American (42.9%, n=9). Over half of patients were stage II at initial diagnosis (61.9%, n=13), while 38.1% (n=8) were stage III. The majority had ductal histology (90.5%, n=19) and had Grade 3 tumors (90.5%, n=19). Of the 21 patients with locoregional recurrence, less than one-tenth (9.5%, n=2) had achieved pathologic complete response (pCR) prior to their recurrence, compared to 41.2% (n=127) of the 308 patients receiving neoadjuvant treatment. In terms of treatment following locoregional recurrence, two-thirds of patients received radiation therapy (66.6%, n=14) with median duration of 47.5 days. Over half of patients (57.1%, n=12) had mastectomy following recurrence, while 14.3% (n=3) had partial mastectomy (breast conserving surgery). Most patients (85.7%, n=18) received systemic chemotherapy after recurrence. Median duration of systemic therapy following locoregional recurrence was 108 days. Nearly one-half (47.6%, n=10) had a subsequent metastatic diagnosis and nearly one-third (28.6%, n=6) had a record of death. Median time from locoregional recurrence to metastatic diagnosis was 36.6 months, but median time from locoregional recurrence to death was not reached. Conclusions: Among patients who received neoadjuvant therapy for ESTNBC in the real-world setting, nearly 7% (n=21) experienced locoregional recurrence. Nearly one-fourth of those patients had a prior pCR which potentially suggests a higher risk of recurrence associated with ESTNBC patients. Chemotherapy was the mainstay of treatment following recurrence. Most patients also received radiation therapy and surgery, but despite those nearly one-half of the patients went on to have a subsequent metastatic diagnosis. This probably reflects the limitations of existing treatment modalities for ESTNBC patients. Future studies with a bigger sample size could confirm our findings. Our study provides some benchmark perspective to such future studies.

Citation Format: Amin Haiderali, Whitney C. Rhodes, Santosh Gautam, Min Huang, Jan Sieluk, Karen E. Skinner, Lee S. Schwartzberg. Locoregional recurrence in patients with early-stage triple-negative breast cancer receiving neoadjuvant systemic therapy: Patient characteristics and clinical outcomes [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS13-42.

Abstract PS9-59: Pooled efficacy analysis from two phase 3 studies in patients receiving eflapegrastim, a novel, long-acting granulocyte-colony stimulating factor, following TC for early-stage breast cancer

Background: Eflapegrastim (Rolontis®, Efla) represents the first novel, long-acting granulocyte-colony stimulating factor (G-CSF) to be introduced in more than 15 years. Efla consists of a recombinant human G-CSF analog conjugated to a human IgG4 Fc fragment via a polyethylene glycol linker. Preclinical, clinical, and pharmacodynamic/pharmacokinetic data have shown increased potency for Efla versus pegfilgrastim (Peg). Both independent, randomized Phase 3 studies comparing Efla and Peg for prophylaxis of chemotherapy-induced neutropenia in patients with early-stage breast cancer (ESBC) met the primary endpoint of non-inferiority in duration of severe neutropenia (SN; ANC&lt;0.5 × 109/L) (p&lt;0.001) for Efla vs Peg in all 4 treatment cycles. Additionally, one of the studies exhibited a statistically significant reduction in the relative risk of SN in Cycle 1 with Efla. Here we provide a pooled analysis across the two pivotal studies comparing Efla vs Peg for SN in various subgroups. Methods: Patients with ESBC, who were candidates for adjuvant or neoadjuvant chemotherapy, were randomized 1:1 in two open-label Phase 3 studies to fixed-dose Efla (3.6 mg G-CSF) or standard Peg (6 mg G-CSF) administered on Day 2 following TC (docetaxel/cyclophosphamide) for a total of 4 cycles. ANCs were collected daily in Cycle 1 and 5 times in Cycles 2-4. SN was evaluated between treatment groups in Cycle 1 using Fisher’s exact test at 5% level of significance and was analyzed using multivariate logistic and Cox proportional hazards regression models. Results: A total of 643 patients who received either Efla (n=314) or Peg (n=329) were included in the analysis. The two treatment groups were well balanced for demographics and baseline characteristics. The mean age was 59 years, 38% were ≥65 years old, and 54% weighed &gt;75kg. The safety profiles, including AEs and discontinuations, for Efla and Peg were comparable, and &gt;99% of all patients received full dose of TC on schedule. The majority (67%) of patients with SN experienced a 1 day duration, occurring between Days 7 and 8 after TC. Mean duration of SN for Efla was statistically lower than for Peg (0.24 vs. 0.36 days; p=0.029). The above statistical significance was maintained for Efla after adjusting for demographic and baseline characteristics, namely age, weight, enrolling geographical region, and treatment setting in a multivariate model. Similarly, the incidence of SN for Efla was statistically lower than Peg in Cycle 1 (17.5% vs 24%; relative risk reduction [RRR]=27%; p=0.043). Univariate analysis of the incidence of SN showed a significant risk reduction in favor of Efla (8.6% vs 14.1%; p=0.034) for patients weighing &gt;75kg (p=0.034). Multivariate analysis of SN showed significant odds ratio of SN for age ≥65 years and baseline ANC &gt;6 × 109/L in favor of Efla (OR=0.42 and 0.39, respectively). The incidence of SN in Cycles 2-4 was comparable between treatment groups. Also, the incidence of febrile neutropenia and neutropenic complications was similar with &lt;5% in each treatment group. No leukocytosis, splenic rupture, or anaphylaxis was reported in any patient receiving Efla or Peg. Conclusion: A pooled analysis of two, randomized Phase 3 studies evaluating Efla vs Peg, administered once-per-cycle for prophylaxis of SN, showed Efla and Peg had similar safety profiles with Efla demonstrating a statistically significant risk reduction in SN overall and in patients weighing &gt;75kg. Eflapegrastim is a novel, long-acting and potent recombinant human G-CSF which may provide an attractive option in supporting patients at risk for SN-related complications.

Citation Format: Lee S Schwartzberg, Gajanan Bhat, Alvaro Restrepo, Osama Hlalah, Inderjit Mehmi, Yong Wha Moon, Seungjae Baek, Shanta Chawla, Francois Lebel, Patrick Wayne Cobb. Pooled efficacy analysis from two phase 3 studies in patients receiving eflapegrastim, a novel, long-acting granulocyte-colony stimulating factor, following TC for early-stage breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS9-59.

Abstract OT-06-01: Open-label, phase 1 study to evaluate duration of severe neutropenia after same-day dosing of eflapegrastim in patients with breast cancer receiving docetaxel and cyclophosphamide (NCT04187898)

Background: Eflapegrastim (Rolontis®, Efla) is a long-acting granulocyte-colony stimulating factor (G-CSF), consisting of a recombinant human G-CSF analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. Efla is not a biosimilar and represents the first myeloid growth factor innovation in more than 15 years. In preclinical studies with chemotherapy-induced neutropenic rats, Efla showed ~3-fold higher exposure in serum and higher exposure in bone marrow at similar doses compared to pegfilgrastim (Peg). The duration of neutropenia (DN) was shown to be significantly shorter with Efla vs Peg when administered on the same day and 24-hours post-chemotherapy. Additionally, the DN after Efla administered on the same day as chemotherapy was similar to the DN 24 hours post-chemotherapy. Moreover, in two Phase 3 studies that randomized a total of 643 patients with early-stage breast cancer (ESBC) to either Efla (3.6 mg G-CSF n=314) or Peg (6 mg G-CSF n=329) given ~ 24 hours after docetaxel and cyclophosphamide (TC) administration, the duration of severe neutropenia (DSN) was statistically noninferior in patients treated with Efla compared to Peg. As a standard of practice, G-CSF products require administration 24 hours after chemotherapy. Since Efla preclinical and clinical results suggest that the increased activity of Efla may provide effective prophylaxis against chemotherapy-induced neutropenia when administered on the same day as chemotherapy, the purpose of this study is to assess the feasibility of Efla same-day (3 different dosing timepoints) in patients receiving TC for treatment of ESBC. Trial Design: This is a randomized, schedule finding, multicenter, Phase 1, open-label study evaluating the same-day administration of 13.2 mg/0.6 mL Efla (3.6 mg G-CSF) following IV infusion of docetaxel (75 mg/m2) and cyclophosphamide (600 mg/m2) in patients with ESBC. Patients will be randomized 1:1:1 to Efla dose schedules of 0.5, 3, and 5 hours after TC. The primary endpoint is DSN (ANC &lt;0.5×109/L) in Cycle 1. The secondary endpoints for Cycle 1 administration include the incidence of SN, time to recovery from SN, incidence of Grade 3 febrile neutropenia, incidence of neutropenic complications, and pharmacokinetics (PK) of Efla. Blood for hematology will be drawn daily for the first 10 days and then on Day 1 of Cycles 2-4. Eligibility Criteria: This study is enrolling histologically confirmed (operable stage I-IIIA) patients with ESBC, who are &gt;18 years of age, are candidates for neoadjuvant or adjuvant TC chemotherapy, have an ECOG of &lt;2, with adequate hematological, renal, and hepatic function. Patients will be excluded if they have a known sensitivity or previous reaction to E. coli derived products, exposure to a G-CSF agent within 3 months, history of bone marrow or hematopoietic stem cell transplant, radiotherapy or surgery within 30 days, are pregnant, or are breast-feeding. Statistical Methods: A sample size of 15 patients per dosing schedule arm was determined to provide adequate precision for the 95% CI of the DSN and secondary endpoints, including PK parameters. The sample size produces a 2-sided 95% CI with a distance from the mean DSN to the limits that is equal to 0.554 using t-distribution when the estimated standard deviation is 1.0 days. A safety evaluation will be performed once the first three patients in each arm have completed Cycle 1. Target Accrual: 45 patients (15 subjects/arm). Enrollment began in April 2020.

Citation Format: Lee S. Schwartzberg, Jawad Francis, Hlalah Osama, Manuel Modiano, Jayaram Bharadwaj, Shanta Chawla, Gajanan Bhat, Francois Lebel, Nishan Tchekmedyian. Open-label, phase 1 study to evaluate duration of severe neutropenia after same-day dosing of eflapegrastim in patients with breast cancer receiving docetaxel and cyclophosphamide (NCT04187898) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr OT-06-01.

Real-world effectiveness outcomes in patients diagnosed with metastatic triple-negative breast cancer

Aim: This study examined treatment patterns and effectiveness outcomes of patients with metastatic triple-negative breast cancer (mTNBC) from US community oncology centers. Materials & methods: Eligible patients were females, aged ≥18 years, diagnosed with mTNBC between 1 January 2010 and 31 January 2016. Kaplan-Meier and Cox regression methods were used. Results: Sample comprised 608 patients with average age of 57.5 years and 505/608 patients (83.1%) received systemic treatment. Overall survival (OS) from first-line treatment found that African-American patients had shorter OS than White (9.3 vs 13.7 months; hazard ratio: 1.35; p = 0.006). Conclusion: More than 15% of women with mTNBC were not treated, indicating a high unmet need. Overall prognosis remains poor, which highlights the opportunity for newer therapies to improve progression-free survival and OS.

Assessing direct costs of treating metastatic triple-negative breast cancer in the USA

Aim: Evaluation of monthly cost during metastatic triple-negative breast cancer (mTNBC) treatment. Patients & methods: Retrospective electronic medical record review of US females aged ≥18 years diagnosed with mTNBC between 1 January 2010 and 31 January 2016. Mean monthly costs per patient were evaluated from start of mTNBC treatment until transfer to hospice, end of record or 3 months prior to death. Results: The mean monthly cost of first line was $21,908 for 505 treated patients; 50.2% of cost was attributable to hospitalization and emergency department visits, and 32.7% to anticancer therapy. Similar patterns were observed for subsequent lines of therapy. Conclusion: The majority of costs were attributable to hospitalization and emergency department services, suggesting a need for effective interventions to reduce utilization of costly services.

Use of antiemetic prophylaxis and oral breakthrough medication for highly emetogenic chemotherapy (HEC) in a large community oncology network

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Background: Prophylaxis for highly emetogenic chemotherapy (HEC) is well established in clinical guidelines, but real-world treatment patterns are unclear. Today, consistent use of prophylaxis is more easily accomplished due to the incorporation of ordering premeds into the workflow prior to administration of intravenous chemotherapy. However, prescription of oral agents for treatment of breakthrough chemotherapy induced nausea and vomiting (CINV) is less consistent and standardized and has a scant evidence base. In an effort to standardize utilization, we evaluated the use of prophylaxis and oral breakthrough medications in a large national community oncology network. Methods: Data from electronic medical records at five practices comprising over 100 clinic sites was analyzed to examine the frequency of guideline-recommended triplet 5-HT3 receptor antagonist, NK-1 receptor antagonist, and corticosteroid use for prophylaxis prior to the administration of HEC agents. Oral breakthrough medication use and preference was also analyzed. Data was collected and analyzed at the practice level. Results: We identified 2645 patients that received HEC between 1/1/2019 and 5/8/2020. We found consistently high utilization of guideline-concordant triplet prophylaxis regimens for patients receiving HEC, ranging from 90-100% at each of the five practices. In addition, most patients (mean 83%, range 67% - 94%) received a prescription for at least one oral breakthrough medication, but the agent(s) utilized varied widely across practices (Table). Ondansetron was the most commonly prescribed oral breakthrough medication (mean 68%, range 53% - 88%), while olanzapine use for either prophylaxis or breakthrough CINV across practices ranged from 1% - 4%. Conclusions: In this national community oncology network, standard recommended triplet agent prophylaxis for HEC was delivered successfully. However, opportunity exists to increase appropriate use of olanzapine and reduce variation of oral breakthrough antiemetic medications in order to optimize clinical care. [Table: see text]

Real-world patterns of chemotherapy and immunotherapy utilization at end of life in a large community oncology network

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Background: End-of-life anti-neoplastic treatment does not improve quality of life nor prolong survival of advanced cancer patients. It is also not cost-effective. To-date, there has been little data examining real-world patterns of chemotherapy and immunotherapy treatment at end of life. We investigated use of chemotherapy and/or immunotherapy in the last 14 days of life across a community oncology network of 5 practices, 100 sites of care, and 160 oncology providers. Methods: Using a real-time, network-wide database, we identified patients with solid tumor malignancies who died during an episode of active treatment, defined as having received intravenous (IV) chemotherapy and/or immunotherapy within 90 days of death. We then identified patients in this cohort who received IV chemotherapy and/or IV immunotherapy within 14 days of death (TxEoL). We studied TxEoL patterns by cancer type, treatment type, line of therapy, patient age, patient race, and oncology provider years in practice. Statistical significance was assessed using Pearson’s Chi-squared test. Results: 2,858 qualifying solid tumor cancer patients with dates of death between 1/1/2019 and 5/31/2020 were identified. Observed rates of TxEoL were 16.7% for immunotherapy alone vs. 19.6% for chemotherapy +/- immunotherapy (p = 0.09). We found high variation in TxEoL across 132 oncologists that had 5 or more deceased patients (range: 0% to 50%, mean: 19.2%, median: 19.6%). We found no association of TxEOL with physician years in practice, patient age or race. Rates of TxEoL in the first-line setting were significantly higher than in second-line setting or later (23.3% versus 16.4%, p < 0.01). Patients with head and neck, pancreatic, and hepatobiliary malignancies were the most likely to receive TxEoL, while patients with prostate, brain, and ovarian malignancies were the least likely to receive TxEoL. Conclusions: Our data and method identified wide variation in TxEoL patterns across a large community oncology network, suggesting room for provider-level interventions to improve treatment decisions in patients at high risk of death. Studies within our group, such as examining the impact of palliative care referrals on IV anti-cancer treatment in patients potentially facing end of life, are ongoing.

Feasibility of and associated cost savings from transitioning to therapeutic biosimilar use in a large community oncology network

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Background: The use of biosimilar drugs in the treatment of cancer offer an opportunity for oncology providers to decrease total cost of care while preserving quality. However, it remains unclear whether providers and patients may resist biosimilar use due to concerns over safety and efficacy. Our national network of 5 practices with over 100 clinics committed to a conversion to therapeutic biosimilars for trastuzumab and bevacizumab after their introduction in July 2019. Methods: Common steps to foster therapeutic biosimilar conversion included frequent communication from medical directors to providers and staff, incorporation of biosimilars into default treatment regimen orders, providing clinical teams lists identifying candidates for conversion, and tracking reasons why biosimilar switch did not occur. Most practices prioritized converting patients initiating new treatments, then later transitioning patients receiving maintenance therapy. This phased approach was taken to ensure that prior authorization and patient consent could be obtained prior to conversion. Rates of biosimilar use were calculated by comparing the number of administrations for which a biosimilar was given to the total number of administrations for which a biosimilar could have been given. Cost savings were calculated by comparing the difference in Medicare allowed rates for each originator and biosimilar drug pair at the time of administration. Results: Biosimilar use increased over time at all practices, from 0% to an average of 67% for trastuzumab and 78% for bevacizumab. The decrease in cost attributed to the use of biosimilars in the study period totaled over $4.4 million. Challenges to biosimilar use included physician preference for the originator drug, difference in preferred agents across payers, and challenges with biosimilar drug storage. Patients rarely had concerns over efficacy and safety. Conclusions: Therapeutic biosimilar adoption in a large oncology network is feasible and can lead to significant cost savings. [Table: see text]

Finding value in social media: A collaborative online communication platform linking providers to education and an online tumor board across a large community of oncology practices

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Background: Clinical collaboration across fragmented and often small clinic sites can be challenging. As a potential solution, OneOncology, a national community oncology network, launched OneCommunity, a secure, interactive online platform used across our network of six practices and over 130 clinic sites. One feature is a “virtual” tumor board where physicians can post complex cases at any time and obtain input from disease-specific experts from within the network. Members can also post, comment and disseminate information about policy and education updates affecting oncology. Methods: OneCommunity launched on December 15, 2019 and all 442 members of OneOncology were allowed access. We tracked numbers of membership, tumor board cases, policy updates and questions, views and responses per post, and response time for tumor board and policy posts during the study period from launch through June 11, 2020. Results: In the first six months of use, 277 providers signed up and logged into the platform. 71 individual patient cases were presented across 10 specialty tumor boards. The mean time to first response was 35 hours ( < 1 hour, 297 hours), median time was 20 hours, and 73% of postings had a response within 48 hours of original posting. The most robust tumor boards were breast, GI, and lung cancers. There was also a set of general posts that was nonspecific to patients including policy, COVID updates, and educational reviews. The average number of responses for tumor boards was significantly greater than general posts (3.5 vs. 1.8, p < 0.05). The number of views for both types of posts, however, were high (406 vs. 346, p < 0.05). Conclusions: An online communication platform is feasible and allows physicians to receive treatment suggestions for complex cases relatively quickly and across geographies. Tumor board cases received more interaction than policy and education updates. The platform lends itself to rapidly adding other aspects of cancer care such as COVID-19. Future applications include a network wide real-time molecular tumor board.

Prevalence of Phosphatidylinositol-3-Kinase (PI3K) Pathway Alterations and Co-alteration of Other Molecular Markers in Breast Cancer

Background: PI3K/AKT signaling pathway is activated in breast cancer and associated with cell survival. We explored the prevalence of PI3K pathway alterations and co-expression with other markers in breast cancer subtypes. Methods: Samples of non-matched primary and metastatic breast cancer submitted to a CLIA-certified genomics laboratory were molecularly profiled to identify pathogenic or presumed pathogenic mutations in the PIK3CA-AKT1-PTEN pathway using next generation sequencing. Cases with loss of PTEN by IHC were also included. The frequency of co-alterations was examined, including DNA damage response pathways and markers of response to immuno-oncology agents. Results: Of 4,895 tumors profiled, 3,558 (72.7%) had at least one alteration in the PIK3CA-AKT1-PTEN pathway: 1,472 (30.1%) harbored a PIK3CA mutation, 174 (3.6%) an AKT1 mutation, 2,682 (54.8%) had PTEN alterations (PTEN mutation in 7.0% and/or PTEN loss by IHC in 51.4% of cases), 81 (1.7%) harbored a PIK3R1 mutation, and 4 (0.08%) a PIK3R2 mutation. Most of the cohort consisted of metastatic sites (n = 2974, 60.8%), with PIK3CA mutation frequency increased in metastatic (32.1%) compared to primary sites (26.9%), p < 0.001. Other PIK3CA mutations were identified in 388 (7.9%) specimens, classified as "off-label," as they were not included in the FDA-approved companion test for PIK3CA mutations. Notable co-alterations included increased PD-L1 expression and high tumor mutational burden in PIK3CA-AKT1-PTEN mutated cohorts. Novel concurrent mutations were identified including CDH1 mutations. Conclusions: Findings from this cohort support further exploration of the clinical benefit of PI3K inhibitors for "off-label" PIK3CA mutations and combination strategies with potential clinical benefit for patients with breast cancer.

A comparison of eflapegrastim to pegfilgrastim in the management of chemotherapy-induced neutropenia in patients with early-stage breast cancer undergoing cytotoxic chemotherapy (RECOVER): A Phase 3 study

Eflapegrastim (Rolontis^®) is a novel, long‐acting hematopoietic growth factor consisting of a recombinant human granulocyte‐colony stimulating factor (rhG‐CSF) analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. We report results from a second pivotal, randomized, open‐label, Phase 3 study comparing the efficacy and safety of eflapegrastim to pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia. Patients with Stage I to IIIA early‐stage breast cancer (ESBC) were randomized 1:1 to fixed‐dose eflapegrastim 13.2 mg (3.6 mg G‐CSF) or pegfilgrastim (6 mg G‐CSF) administered one day after standard docetaxel/cyclophosphamide (TC) therapy for four cycles. The primary objective was to demonstrate noninferiority (NI) of eflapegrastim compared to pegfilgrastim in mean duration of severe neutropenia (DSN; Grade 4) in Cycle 1. A total of 237 eligible patients were randomized 1:1 to receive either eflapegrastim (n = 118) or pegfilgrastim (n = 119). Cycle 1 severe neutropenia was observed in 20.3% (n = 24) of patients receiving eflapegrastim and 23.5% (n = 28) receiving pegfilgrastim. The DSN of eflapegrastim in Cycle 1 was noninferior to pegfilgrastim with a mean difference of −0.074 days (NI P‐value < .0001). Noninferiority was maintained throughout the four treatment cycles (P < .0001 in all cycles). Other efficacy endpoints results were comparable between treatment arms, and adverse events, irrespective of causality and grade, were comparable between treatment arms. The results demonstrate noninferior efficacy and comparable safety for eflapegrastim, at a lower G‐CSF dose, vs pegfilgrastim. The potential for the increased potency of eflapegrastim to deliver improved clinical benefit warrants further clinical study.

Liquid biopsy mutation panel for non-small cell lung cancer: analytical validation and clinical concordance

Molecular testing for genomic variants is recommended in advanced non-small cell lung cancer (NSCLC). Standard tissue biopsy is sometimes infeasible, procedurally risky, or insufficient in tumor tissue quantity. We present the analytical validation and concordance study of EGFR variants using a new 17-gene liquid biopsy assay (NCT02762877). Of 144 patients enrolled with newly diagnosed or progressive stage IV nonsquamous NSCLC, 140 (97%) had liquid assay results, and 117 (81%) had both EGFR blood and tissue results. Alterations were detected in 58% of liquid samples. Overall tissue-liquid concordance for EGFR alterations was 94.0% (95% CI 88.1%, 97.6%) with positive percent agreement of 76.7% (57.7%, 90.1%) and negative percent agreement of 100% (95.8%, 100%). Concordance for ALK structural variants was 95.7% (90.1%, 98.6%). This assay detected alterations in other therapeutically relevant genes at a rate similar to tissue analysis. These results demonstrate the analytical and clinical validity of this 17-gene assay.

Eflapegrastim, a Long-Acting Granulocyte-Colony Stimulating Factor for the Management of Chemotherapy-Induced Neutropenia: Results of a Phase III Trial

Background

Eflapegrastim, a novel, long‐acting recombinant human granulocyte‐colony stimulating factor (rhG‐CSF), consists of a rhG‐CSF analog conjugated to a human IgG4 Fc fragment via a short polyethylene glycol linker. Preclinical and phase I and II pharmacodynamic and pharmacokinetic data showed increased potency for neutrophil counts for eflapegrastim versus pegfilgrastim. This open‐label phase III trial compared the efficacy and safety of eflapegrastim with pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia.

Materials and Methods

Patients with early‐stage breast cancer were randomized 1:1 to fixed‐dose eflapegrastim 13.2 mg (3.6 mg G‐CSF) or standard pegfilgrastim (6 mg G‐CSF) following standard docetaxel plus cyclophosphamide chemotherapy for 4 cycles. The primary objective was to demonstrate the noninferiority of eflapegrastim compared with pegfilgrastim in mean duration of severe neutropenia (DSN; grade 4) in cycle 1.

Results

Eligible patients were randomized 1:1 to study arms (eflapegrastim, n = 196; pegfilgrastim, n = 210). The incidence of cycle 1 severe neutropenia was 16% (n = 31) for eflapegrastim versus 24% (n = 51) for pegfilgrastim, reducing the relative risk by 35% (p = .034). The difference in mean cycle 1 DSN (−0.148 day) met the primary endpoint of noninferiority (p < .0001) and also showed statistical superiority for eflapegrastim (p = .013). Noninferiority was maintained for the duration of treatment (all cycles, p < .0001), and secondary efficacy endpoints and safety results were also comparable for study arms.

Conclusion

These results demonstrate noninferiority and comparable safety for eflapegrastim at a lower G‐CSF dose versus pegfilgrastim. The potential for increased potency of eflapegrastim to deliver improved clinical benefit warrants further clinical study in patients at higher risk for CIN.

Implications for Practice

Chemotherapy‐induced neutropenia (CIN) remains a significant clinical dilemma for oncology patients who are striving to complete their prescribed chemotherapy regimen. In a randomized, phase III trial comparing eflapegrastim to pegfilgrastim in the prevention of CIN, the efficacy of eflapegrastim was noninferior to pegfilgrastim and had comparable safety. Nevertheless, the risk of CIN remains a great concern for patients undergoing chemotherapy, as the condition frequently results in chemotherapy delays, dose reductions, and treatment discontinuations.

Myelosuppression, particularly neutropenia, has presented a major challenge in cancer treatment since the introduction of cytotoxic chemotherapy. This article reports the results of a phase III trial that compared the efficacy and safety of eflapegrastim with pegfilgrastim for reducing the risk of chemotherapy‐induced neutropenia.

Real-world evaluation of effectiveness and tolerance of chemotherapy for early-stage breast cancer in older women

PURPOSE

Older patients with early-stage breast cancer (ESBC) tend to receive less aggressive treatment, have higher mortality rates, and are underrepresented in clinical trials. Outcomes, tolerance and toxicity of chemotherapy are underreported. Thus, we assessed the outcomes of chemotherapy in the real-world in a community oncology setting.

METHODS

We retrospectively chart reviewed consecutive older patients (≥ 70 years) with ESBC diagnosed between January 1, 2010, and December 31, 2016, who received chemotherapy at our institution. Study outcomes were survival estimates. Logistic regression determined associations with measures of intolerance.

RESULTS

Of 1296 patients, 229 received chemotherapy. Overall, 24% had early chemotherapy cessation; 18% had dose reductions; and 27% had dose delays. Severe, life threatening and lethal toxicities occurred in 38%, 1.3%, and 2.2%, respectively; constitutional toxicity (37%) was the most common. The 1- and 3-year overall survivals were 94% and 79%; 1- and 3-year breast-specific survivals were 96% and 89%, while 1- and 3-year disease-free survivals were 95% and 82%, respectively. Anthracyclines were the most poorly tolerated regimen having associations with hospital visits (OR 10.97, 95% CI 2.10-57.23) and severe toxicities (OR 5.28, 95% CI 1.27-21.89). Anti-HER2 therapies (OR 3.03, 95% CI 1.18-7.78) and poorer performance status (PS) (OR 7.48, 95% CI 1.75-31.98) were associated with severe toxicities. Older age (> 80 years) was associated with early cessation of therapy (OR 3.64, 95% CI 1.34-9.83).

CONCLUSIONS

Chemotherapy can be effectively delivered to older patients with ESBC and is reasonably well tolerated. The high rate of anthracycline intolerability, poorer PS, and advanced age should be considered when tailoring treatment regimens.

Racial and socioeconomic disparities in overall survival in colorectal cancer (CRC) at West Cancer Center & Research Institute (WCCRI), Memphis, TN

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Background: WCCRI, a comprehensive regional community oncology center in Memphis, Tennessee and the Mid-South region, serves a racially, geographically and socioeconomically diverse patient cohort. We sought to evaluate disparity of outcomes in survival by race and socioeconomic status, in addition to patient and tumor characteristics. Methods: All consecutive patients referred to and treated at WCCRI with colorectal adenocarcinoma from 2007-2013 were included. Individual chart review was performed to verify diagnosis, stage, and date and cause of death. Kaplan-Meier Overall Survival curves were generated for the entire cohort and by race, sex, tumor location and income derived from zip code. WCCRI survival data were compared to SEER data. Results: From 2007-2013, 1,176 patients were included in the analysis: 405 blacks, 757 whites, 14 others. Median age at diagnosis: Blacks 58 yrs, whites 61 yrs. Stage distribution at diagnosis: stage 1: 100, stage 2: 275, stage 3: 425, stage 4: 376. All stages combined, blacks trended towards shorter OS vs whites (5-year OS: 52.8% vs 58.3%; median survival 71.0 mos vs 98.6 mos; p= 0.095). Blacks presented at later stages (71.4% at stage 3 or 4 vs 66.3% for whites) but no statistically significant OS differences were seen when compared by stage. Patients at or below the median income of $39,590 for WCC had worse 5-year OS (51.6% vs. 61.1%; p= 0.006), as did patients without private insurance (5-year OS: uninsured: 48.0%, Medicare/Medicaid: 50.0%, private: 62.0%; p< 0.001). Adjusted for stage, 5-year OS was statistically significant for stage 4 (private: 18.0%, Medicare/Medicaid: 9.4%, uninsured: 8.3%; p= 0.020). A higher proportion of blacks were below the median income (69% vs 39%) but no statistically significant OS differences were seen when adjusted by race. Overall, cancer survival outcomes were similar to SEER results. Conclusions: At WCCRI, black patients with CRC presented at a later stage than whites, however, adjusted for stage, no significant racial difference in OS was found. Income and insurance status influenced survival outcomes. Overall, our results reveal racial and socioeconomic disparities in colorectal cancer in a diverse US population and further detailed multivariate data analyses are underway.

Real-world incidence, duration, and severity of treatment-emergent (TE) neutropenia among patients (pts) with metastatic breast cancer (MBC) treated with ribociclib (RIB) or palbociclib (PAL)

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Background: Neutropenia is the most common adverse event following administration of CDK4/6 inhibitors RIB and PAL for hormone receptor–positive (HR+) MBC. There are limited comparative real-world data on TE neutropenia in pts receiving these agents. Here we report incidence, duration, and severity data on TE neutropenia in such pts from an electronic health record dataset and administrative claims. Methods: This retrospective study comprised 2 mutually exclusive cohorts of pts with MBC receiving RIB or PAL. Pts were matched 1:1 based on age and year of treatment start. Prior baseline activity of ≥6 mo was required. The MarketScan claims databases was used to evaluate incidence rates of TE neutropenia from Jan 1, 2015, to Dec 31, 2018, in pts receiving RIB or PAL. Rate ratio was calculated using a Poisson model. Data on neutropenia severity and duration were obtained from Optum de-identified Electronic Health Record dataset. Neutropenia severity was defined by neutrophil counts from lab tests (grade 1/2, 1000- < 1500/μL; grade 3, 500- < 1000/μL; grade 4 < 500/μL) within the first 180 days of treatment. Neutropenia duration was estimated using Kaplan-Meier analysis and defined as the time between first abnormal neutrophil result and a lab result demonstrating neutropenia resolution. Results: After 1:1 matching, 152 pts from the MarketScan database were included in both the PAL and RIB cohorts; 168 matched pts were included from the Optum dataset. Neutropenia was reported in 38 pts (25%) in the PAL group and 25 pts (17%) in the RIB group. The rate of neutropenia per person–treatment year was 0.5 (95% CI, 0.4-0.7) in PAL pts vs 0.4 (95% CI, 0.3-0.6) in RIB pts. The rate ratio of neutropenia between treatments (PAL vs RIB) was 1.4 (95% CI, 0.8-2.3), which was not statistically significant, likely due to small sample size. Rates of neutropenia by severity with PAL vs RIB were 32% vs 32% for grade 1/2, 35% vs 26% for grade 3, and 4% vs 4% for grade 4, respectively. The rate ratio for grade 3 or grade 4 neutropenia (PAL vs RIB) was 1.3 (95% CI, 0.9-1.8). Median neutropenia duration was 29 vs 20 days ( P< .01) with PAL vs RIB. Conclusions: Treatment of HR+ MBC with RIB and PAL requires optimal management of TE neutropenia. Real-world data showed that pts with MBC receiving PAL had a numerically higher rate of neutropenia than pts receiving RIB. Rates of grade 3 neutropenia were higher with PAL vs RIB, and duration of neutropenia was longer with PAL vs RIB. Economic burden analyses of neutropenia will be presented.

Work loss and activity impairment due to duration of nausea and vomiting in patients with breast cancer receiving CINV prophylaxis

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Background: The impact of chemotherapy-induced nausea and vomiting (CINV) on work loss and activity impairment is important to patients yet not well described in literature. We sought to evaluate CINV-related work loss and activity impairment and their associations with CINV duration. Methods: In a prospective CINV prophylaxis trial of oral or intravenous netupitant/palonestron (NEPA) + dexamethasone (DEX) (12mg day 1 only) for patients with breast cancer receiving anthracycline + cyclophosphamide (AC), we defined CINV as vomiting or use of rescue medication during days 1-5 after AC. Pre-specified endpoints included CINV duration (0-5 days), patient reported CINV-associated work loss (Work Productivity and Activity Impairment survey), and CINV-related impaired activity [0 (none) - (worst) Likert scale] for chemotherapy cycles 1 and 2. CINV-related work loss and activity impairment could involve nausea with or without vomiting or rescue medication use. We categorized CINV duration as 1-2 days (d) or ≥3 d, and compared results using the chi-squared test. We report here on the first 2 cycles. Results: Survey data was captured for 792 cycles in 402 female patients including 132 (32.8%) employed patients. Mean age was 55.4. CINV was observed in 173 (21.8%) of total cycles. CINV-related work loss was reported in 26 (3.3% of all cycles, 15.0% of cycles with CINV, 38.2% of employed patient cycles with CINV) while 142 had related activity impairment. When we categorized cycles by CINV duration, CINV-related work loss was seen in 25.9% of 81 cycles with ≥3 d CINV duration vs. 5.4% for 92 cycles of 1-2 d of CINV (p < 0.001); mean scores of CINV-related impaired activity were 5.0 for ≥3 d CINV vs 3.0 for 1-2 d CINV (p < 0.001). Conclusions: Despite guideline recommended prophylaxis, CINV occurred in > 20% of AC cycles. In cycles with CINV, CINV-related work loss occurred in 38.2% for employed patients while activity impairment occurred in 82.1% for all patient cycles. The majority of CINV lasted 1-2 d. Notably, ≥3 d of CINV was associated with considerably higher levels of work loss and activity impairment suggesting that duration may be a meaningful measure of CINV impact. Clinical trial information: NCT03403712 . [Table: see text]

Using an ePRO tool to help meet quality metric reporting standards: Screening for tobacco usage and falls risk

e19191

Background: ASCO has implemented the Quality Oncology Practice Initiative (QOPI), a certification program established to evaluate oncology practice performance. Also, a growing number of accreditation (JCAHO) and merit-based organizations (MIPS) maintain falls risk assessment standards. Practices often lack the necessary resources to comply with required metric reporting standards. The study purpose was to document the effectiveness of using an electronic Patient Reported Outcome (ePRO) system to facilitate compliance with a core QOPI standard, documentation of smoking status by second office visit, and with JCAHO and MIPS falls risk assessment. Methods: This study used a retrospective, observational design with ePRO collected via the Patient Care Monitor (PCM), a web-based ePRO system linked to electronic medical record data. All study data were collected as part of routine clinical care at a community oncology practice during an 11-month interval (1/2019–11/2019). Patients at an initial clinic visit completed a tobacco usage survey and a brief falls risk survey on the PCM platform via a handheld e-tablet. Results: Overall, 6,613 unique patients completed the PCM survey (mean age 59; 33% male/67% female; 55.4% White, 38% Black). Cancer type was known for a subset of patients (22% breast, 9% hematologic, 4% lung, 5% colorectal, 3% prostate, 11% other types). Across the collected PRO measures, there was an over 98% completion rate with only 1-2% missing data. A relatively significant proportion (51%) indicated they had never used tobacco products and 15% indicated that they were current users. Among patients who ever used tobacco products, 34% indicated they smoked cigarettes, 4% smoked cigars, and 3% used electronic cigarettes. Over a fifth of patients (22%) indicated they had at least one fall over six months; 10% indicated having experienced one fall; 6% indicated two falls; 6% indicated 3 falls or more. 17% indicated they use an ambulatory aid and 12% reported a recent fall within the past 3 months. Conclusions: This study demonstrates that using an ePRO system is an effective way to screen for tobacco usage and falls risk and can be used to: 1) monitor health-related behaviors to enhance physician-patient communication; 2) provide an audit trail for QOPI, JCAHO, MIPS and other quality metric reporting. Automated collection of PRO data allows the healthcare team to focus their clinical time on patients showing increased risk. Overall, an ePRO system contributes to creating a culture of excellence at community oncology practices.

A multi-stakeholder platform to prospectively link longitudinal real-world clinico-genomic, imaging, and outcomes data for patients with metastatic lung cancer

TPS2087

Background: Making personalized diagnostics and treatments a reality for every cancer patient necessitates comprehensively capturing the patient journey. Real-world data has shown promise for the future of clinical research and advancing precision medicine. However, certain limitations exist such as data quality management as well as bias and confounding factors associated with retrospective analyses. We present a multi-stakeholder platform to prospectively collect and link real-world clinico-genomic, imaging, and outcomes data to longitudinal blood genomic profiling for lung cancer. Methods: This study is enrolling approximately 1000 patients with metastatic non-small cell lung cancer or extensive-stage small cell lung cancer who will initiate standard-of-care systemic anti-neoplastic treatment, regardless of line of therapy, at 20 community oncology and academic practices within the Flatiron Health network. Relevant clinical data points from both structured and unstructured fields will be collected through the electronic health records via technology-enabled abstraction, eliminating the need for case report forms. Digital pathology and clinical images at standard-of-care visits will be collected. Blood samples for circulating tumor DNA (ctDNA) profiling using FoundationOne Liquid will be collected at three timepoints: enrollment, first tumor assessment, and end of treatment. Tumor tissue samples may be submitted at baseline for genomic profiling using FoundationOne CDx. Overall survival follow-up will occur until death, withdrawal of consent, loss to follow-up, or end of study. The objectives are to evaluate 1) the feasibility of building a scalable, prospective platform and 2) the associations between ctDNA and real-world clinical outcomes, including overall survival. Enrollment is ongoing. Clinical trial information: NCT04180176.

Use of real-world data to understand barriers to interventional clinical trial enrollment in community oncology clinics (COC)

2061

Background: Increasing enrollment in clinical trials remains a national priority, yet there are limited data from COCs on the degree to which common trial exclusion criteria (EC) and socioeconomic factors play a role in low enrollment rates. Methods: We analyzed data from the nationwide Flatiron Health electronic health record (EHR) derived de-identified database. COC were eligible if they had given a clinical trial study drug to ≥2 patients (pts)/year. We included pts with one of eight advanced or metastatic solid tumors who received ≥1 line of systemic anticancer therapy between 1/1/2014 and 11/30/2019. We defined EC as either: creatinine > 1.5 mg/dl or Ccl < 45 ml/min, Hb < 9 g/dL, ANC < 1500/ul, plts < 100,000/ul, bilirubin > 1.5 upper limit of normal (uln) or AST/ALT > 2.5 uln within 30 days or ECOG performance status (PS) ≥ 2 within 60 days prior to start of therapy. We calculated the percentage of pts with ≥1 EC relative to the group of candidate pts, stratified by therapy line (1L, 2L, 3L+). We used multivariate logistic regression models to evaluate the effect of EC and socioeconomic factors (age, race, Medicaid) on the likelihood of receiving a clinical study drug for each line of therapy. Results: In this sample of 35 COCs, 26,988 pts received ≥1 systemic therapy. Pts with ≥ 1 EC: 28.4% in 1L, 34.2% in 2L, 37.4% in 3L. Percentages of pts with an ECOG PS ≥ 2 were: 15.6% (1L), 18.2% (2L), 19.8% (3L). Pts receiving a clinical study drug: 1.7% of 26,988 in 1L, 2.0% of 12,738 in 2L, 2.9% of 5,333 in 3L+, and 3.1% in any line. Excluding pts with ≥1 EC from the denominator modestly improved overall accrual: 2.0% of 19,729 in 1L, 2.3% of 8,588 in 2L, 3.7% of 3,470 in 3L+. In multivariate logistic regression, ECOG PS ≥ 2 was strongly associated with not receiving a study drug [odds ratio (95% CI); 1L: 0.25 (0.16-0.4); 2L: 0.28 (0.17-0.49); 3L: 0.21 (0.1-0.44)]. The likelihood of receiving a clinical study drug (any line) was lower for pts who are Black [0.63 (0.48-0.82)], Latino [0.49 (0.32-0.75)], and pts older than 70 years [0.63 (0.54-0.72)]. Medicaid pts were not significantly less likely to receive study drug [0.83 (0.64-1.07)]. Conclusions: In COC, common trial EC reduce pt availability for trials by > 25%. Poor PS is highly prevalent and influential. These EC and complex trial requirements challenge COC’s ability to recruit representative pt populations. Future efforts to increase enrollment in trials must consider common EC along with well known barriers to enrollment of unrepresented groups.

CONTESSA TRIO: A multinational, multicenter, phase (P) II study of tesetaxel (T) plus three different PD-(L)1 inhibitors in patients (Pts) with metastatic triple-negative breast cancer (TNBC) and tesetaxel monotherapy in elderly pts with HER2-metastatic breast cancer (MBC)

TPS1111

Background: Chemotherapy treatments with robust efficacy that preserve quality of life are needed. T is a novel, oral taxane that has potential advantages over currently available taxanes, including: oral administration with a low pill burden and once every 3 week (Q3W) dosing; no observed hypersensitivity reactions; preclinical evidence of central nervous system (CNS) penetration; and improved activity against chemotherapy-resistant tumors. More than 600 pts have been treated with T in clinical studies. T had robust monotherapy activity in a P2 study in 38 pts with HER2-, HR+ MBC, with a confirmed objective response rate (ORR) per RECIST 1.1 of 45%. Methods: CONTESSA TRIO is a 2-cohort, multinational, multicenter, P2 study. In Cohort 1, 90 pts (potential expansion to up to 150 pts) with metastatic TNBC who have not received prior chemotherapy for advanced disease will be randomized 1:1:1 to receive T at 27 mg/m2 Q3W plus either: (1) nivolumab at 360 mg Q3W; (2) pembrolizumab at 200 mg Q3W; or (3) atezolizumab at 1,200 mg Q3W. Nivolumab and pembrolizumab (PD-1 inhibitors) and atezolizumab (a PD-L1 inhibitor) are approved for the treatment of multiple types of cancer; atezolizumab, in combination with nab-paclitaxel, was recently approved in the US for the treatment of metastatic TNBC. The dual primary endpoints for Cohort 1 are ORR and progression-free survival (PFS). A sample size of 30 pts in each PD-(L)1 inhibitor treatment group has approximately 70% power to detect an ORR difference of ≥ 35% between the treatment group with the highest ORR and the treatment group with the lowest ORR. Secondary endpoints include duration of response (DoR) and overall survival (OS). Efficacy results for each of the 3 PD-(L)1 inhibitor combinations will be assessed for correlation with the results of each of the 3 approved PD-L1 diagnostic assays. CONTESSA TRIO is the first randomized clinical study to compare 3 approved PD-(L)1 inhibitors. In Cohort 2, 40 elderly pts (potential expansion to up to 60 pts) with HER2- MBC who have not received prior chemotherapy for advanced disease will receive T monotherapy at 27 mg/m2 Q3W. The primary endpoint for Cohort 2 is ORR. A sample size of 40 will allow the ORR to be estimated with a maximum standard error of < 8%. Secondary endpoints include PFS, DoR and OS. Pts with CNS metastases are eligible for both cohorts. The study was initiated in March 2019. Clinical trial information: NCT03952325 .

Treatment Outcomes in Patients with Metastatic Neuroendocrine Tumors: a Retrospective Analysis of a Community Oncology Database

Purpose

Metastatic neuroendocrine tumors (mNETs) are rare, heterogeneous tumors that present diagnostic and treatment challenges, with limited data on the management of mNETs in clinical practice. The present study was designed to identify current diagnostic and treatment patterns in mNET patients treated in the US community oncology setting.

Methods

Patient-level data was collected from medical records of adults with mNETs from the Vector Oncology Data Warehouse, a comprehensive US community oncology network database.

Results

Of the 263 patients included (median follow-up, 22 months; range, 0.1–193.9), 30.4% (80/263) had intestinal tumors, 11.0% (29/263) had pancreatic, and 58.6% (154/263) had tumors of other or unknown location. Progression-free survival (PFS) from the start of first-line therapy differed significantly by tumor grade (log rank P = 0.0016) and location (P = 0.0044), as did overall survival (OS) (grade, P < 0.0001; location, P = 0.0068). Median PFS and OS for patients with undocumented tumor grade were shorter than for patients with G1/G2 tumors and longer than patients with G3 tumors. Median PFS and OS for patients with other or unknown tumors were shorter than for patients with intestinal tumors.

Conclusions

While potentially confounded by the high number of patients with other or unknown tumor locations, this retrospective study of patients in a US community oncology setting identified the importance of awareness of tumor grade and tumor location at diagnosis, as these were direct correlates of PFS and OS.

Targeting PIK3CA Alterations in Hormone Receptor-Positive, Human Epidermal Growth Factor Receptor-2-Negative Advanced Breast Cancer: New Therapeutic Approaches and Practical Considerations

The phosphatidylinositol-3-kinase (PI3K) pathway is frequently dysregulated in human breast cancer. Approximately 30% of all patients with breast cancer will carry mutations of the PIK3CA gene, which encodes the PI3K catalytic subunit isoform p110α. Mutations in PIK3CA have been associated with resistance to endocrine therapy, HER2-directed therapy, and cytotoxic therapy. Early trials of pan-PI3K inhibitors showed little treatment benefit as monotherapy owing to disease resistance arising through enhanced estrogen receptor pathway signaling. Combining PI3K inhibition with endocrine therapy can help overcome resistance. Clinical trials of pan-PI3K inhibitors combined with endocrine therapy demonstrated modest clinical benefits but challenging toxicity profiles, facilitating the development of more selective PI3K-targeting agents. More recent trials of isoform-specific PI3K inhibitors in patients with PIK3CA mutations have shown promising clinical efficacy with a predictable, manageable safety profile. In the present review, we discuss the clinical relevance of mutations of PIK3CA and their potential use as a biomarker to guide treatment choices in patients with HR⁺ HER2^- advanced breast cancer.