Abstract PO-208: Patient-reported out-of-pocket costs and financial toxicity during early- phase oncology clinical trials

Background Clinical trials are an important therapeutic option for cancer patients (pts). Although financial burden in cancer treatment is well-documented, the financial burden associated with clinical trials is not well understood, especially for pts with lower income. Methods We conducted a survey regarding economic burden and financial toxicity in cancer pts who had been on Phase I clinical trials for ≥1 month. Financial Toxicity Score (FTS) was assessed using the validated COmprehensive Score for Financial Toxicity (COST) survey (scale 0-44, lower scores indicate worse toxicity). Pts also reported monthly out-of-pocket (OOP) medical and non-medical expenses. We applied multivariable logistic regression to analyze risk of financial toxicity, and unanticipated expenses. Results Early-phase clinical trial pts (N=213, median age = 59y; 59% female; 74% White, 45% w/ annual income ≤$60K; 54% had employer sponsored insurance; 37% had Medicare; 50% lived >300 miles from the clinic; 37% required air travel) had a median FTS of 20, with interquartile range of 12. Median monthly OOP costs for non-medical expenses was $1075, and for medical expenses was $475. Median total monthly OOP costs was $1750. 55% and 64% of pts reported that actual medical and non-medical expenses were higher than expected, respectively. Worse financial toxicity (≤ median FTS) in pts was associated with yearly household income <$60K (OR: 2.7, P=0.008), having medical costs higher than expected (OR: 3.2, P=0.024), participation on ≥1 Phase I clinical trial prior to their current trial (OR: 2.2, P=0.028), and living >100 miles away from the clinical trials hospital (OR: 2.3, P=0.043). 29% of pts received partial/full reimbursement of clinical trial-related travel costs from study sponsor/other/insurance. Racial/ethnic minority (OR: 2.6, P=0.008) and pts who were unemployed or not working outside the home (OR: 2.4, P=0.023) were more likely to report that actual medical costs were much higher than expected. 53% of pts used savings and 19% borrowed money from friends/family or had a personal fundraiser to pay for treatment. Conclusions Among cancer pts participating on clinical trials, economic burden is high, and most of pts’ OOP costs were on non- medical expenses. Financial toxicity is disproportionally higher in pts with lower income and those who travel farther, and unexpected medical costs were more common among minorities. OOP costs can be substantial and are often unexpected for pts. Future work should focus on methods to reduce disparities in clinical trial participation, including the role of reimbursement of trial-related expenses.

Citation Format: Ryan W. Huey, Goldy C. George, Penny Phillips, Revenda White, Filip Janku, Daniel D. Karp, Aung Naing, Sarina Piha-Paul, Vivek Subbiah, Apostolia M. Tsimberidou, Shubham Pant, Timothy A. Yap, Jordi Rodon, Funda Meric-Bernstam, Ya-Chen Tina Shih, David S. Hong. Patient-reported out-of-pocket costs and financial toxicity during early- phase oncology clinical trials [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-208.

Evaluating the psychometric properties of the Immunotherapy module of the MD Anderson Symptom Inventory

INTRODUCTION

Immunotherapies have revolutionized the treatment of various cancers, but little is known about their symptomatic toxicity. Assessing these symptoms is best accomplished by asking the patients themselves. However, such reports are subjective and may face challenges as bonafide scientific data. Demonstrating the validity of symptom assessment tools, mainly through the reduction of measurement errors, has the potential to improve patient care if these tools are widely adopted. To that end, we present herein the psychometric properties of the Immunotherapy for Early-Phase Trials module of the MD Anderson Symptom Inventory (MDASI-Immunotherapy EPT) in patients receiving various immunotherapies in early phase trials at a major cancer center.

METHODS

One hundred forty-five patients completed the inventory at baseline, with 85 of them also doing so after 9 weeks of treatment. The mean (±SD) age of the patients was 57.0±12.9 years. Also, 56% of the patients were women, 79% identified as white, and 49% had at least some college education.

RESULTS

The internal consistency reliability of the MDASI-Immunotherapy EPT was excellent, as the Cronbach's alphas for all of its subscales were at least 0.88 (range 0.88-0.95). Known-group validity based on Eastern Cooperative Oncology Group performance status groupings was excellent at 9 weeks after the start of an immunotherapy trial for the MDASI-Immunotherapy EPT severity (effect size, 0.96) and interference (effect size, 0.82) subscales. We found substantial changes in the symptom items difficulty remembering (effect size, -0.85), fever and/or chills (effect size, -0.63), disturbed sleep (effect size, -0.52), diarrhea (effect size, -0.42), and swelling of hands, legs, or feet (effect size, -0.39).

CONCLUSIONS

In conclusion, the MDASI-Immunotherapy EPT is a valid, reliable, and sensitive tool for measuring symptomatic toxicity.

Intratumoral Injection of Clostridium novyi-NT Spores in Patients with Treatment-refractory Advanced Solid Tumors

PURPOSE

Intratumorally injected Clostridium novyi-NT (nontoxic; lacking the alpha toxin), an attenuated strain of C. novyi, replicates within hypoxic tumor regions resulting in tumor-confined cell lysis and inflammatory response in animals, which warrants clinical investigation.

PATIENTS AND METHODS

This first-in-human study (NCT01924689) enrolled patients with injectable, treatment-refractory solid tumors to receive a single intratumoral injection of C. novyi-NT across 6 dose cohorts (1 × 10⁴ to 3 × 10⁶ spores, 3+3 dose-escalation design) to determine dose-limiting toxicities (DLT), and the maximum tolerated dose.

RESULTS

Among 24 patients, a single intratumoral injection of C. novyi-NT led to bacterial spores germination and the resultant lysis of injected tumor masses in 10 patients (42%) across all doses. The cohort 5 dose (1 × 10⁶ spores) was defined as the maximum tolerated dose; DLTs were grade 4 sepsis (n = 2) and grade 4 gas gangrene (n = 1), all occurring in three patients with injected tumors >8 cm. Other treatment-related grade ≥3 toxicities included pathologic fracture (n = 1), limb abscess (n = 1), soft-tissue infection (n = 1), respiratory insufficiency (n = 1), and rash (n = 1), which occurred across four patients. Of 22 evaluable patients, nine (41%) had a decrease in size of the injected tumor and 19 (86%) had stable disease as the best overall response in injected and noninjected lesions combined. C. novyi-NT injection elicited a transient systemic cytokine response and enhanced systemic tumor-specific T-cell responses.

CONCLUSIONS

Single intratumoral injection of C. novyi-NT is feasible. Toxicities can be significant but manageable. Signals of antitumor activity and the host immune response support additional studies of C. novyi-NT in humans.

Abstract PR10: PIK3CA mutations in plasma cell-free DNA predict survival and treatment outcomes in patients with advanced cancers

Background: Cell-free DNA (cfDNA) analysis from plasma offers a minimally invasive detection of genomic alterations in personalized cancer therapy. PIK3CA is an actionable gene, which can be targeted with PI3K, AKT and mTOR inhibitors. We hypothesized that common hot-spot PIK3CA mutations can be detected in small amount of plasma cfDNA from patients with progressing advanced cancers.

Methods: PIK3CA mutations (p.H1047R, p.H1047L, p.E542K and p.E545K) were detected by droplet digital PCR (QX 200, BioRad) using 16 ng of unamplified cfDNA from plasma of 68 patients with advanced cancer. Results were compared to the clinical molecular testing of archival tumor tissue performed by next-generation sequencing or PCR during the clinical care.

Results: Of 68 patients (breast cancer, n=41; colorectal cancer, n=13; other tumor types, n=14), 58 patients (85%) had a PIK3CA mutation in the tumor. Testing of plasma cfDNA was in agreement with tumor tissue in 72% of samples (kappa 0.38), sensitivity 67% and specificity 100%. Of 19 falsely negative plasma cfDNA samples, 6 were found to be collected from patients not having disease progression. Additional 9 samples with available cfDNA were retested with increased DNA input (22-247 ng) and 4 had a PIK3CA mutation resulting in agreement for patients with progressing cancers of 85% (kappa 0.61), sensitivity 83% and specificity 100%. Patients with plasma PIK3CA-mutant cfDNA variant-allele frequency (VAF) < 8.5% (<5% trimmed mean) had a longer median survival compared to patients with VAF ≥ 8.5% (68 vs. 40 weeks; P=0.01). Serial collections of plasma cfDNA during systemic therapies were available for 18 patients with a median of 5 time points (range 2-22). Patients with decrease in PIK3CA-mutant VAF in cfDNA compared to increase or no change had a longer time to treatment failure to PI3K pathway-targeted therapies (46 vs. 11 weeks; p=0.04).

Conclusion: Common PIK3CA mutations can be detected in plasma cfDNA with high sensitivity and specificity in patients with progressing cancer if the cfDNA input is sufficient. Low amount of PIK3CA-mutant cfDNA is associated with longer survival. Changes in PIK3CA VAF could be an early surrogate biomarker for time to treatment failure to PI3K-targeted therapies.

This abstract is also being presented as Poster B16.

Citation Format: Ecaterina E. Ileana Dumbrava, Helen J. Huang, Ana Stuckett, Kiran Madwani, Abha Adat, David S. Hong, Sarina A. Piha-Paul, Vivek Subbiah, Daniel D. Karp, Siqing Fu, Aung Naing, Apostolia M. Tsimberidou, Stacey Moulder, Kimberly Koenig, Carlos H. Barcenas, Bryan Kee, David Fogelman, Scott Kopetz, Funda Meric-Bernstam, Filip Janku. PIK3CA mutations in plasma cell-free DNA predict survival and treatment outcomes in patients with advanced cancers [abstract]. In: Proceedings of the AACR Special Conference on Targeting PI3K/mTOR Signaling; 2018 Nov 30-Dec 8; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Res 2020;18(10_Suppl):Abstract nr PR10.

Phase II study of pembrolizumab efficacy and safety in women with recurrent small cell neuroendocrine carcinoma of the lower genital tract

OBJECTIVE

To investigate the efficacy and safety of pembrolizumab in women with recurrent small cell neuroendocrine tumors of the lower genital tract.

METHODS

We conducted an open-label, investigator-initiated phase II basket trial of pembrolizumab 200 mg intravenously every 3 weeks in patients with rare tumors (ClinicalTrials.gov: NCT02721732). The trial had prespecified cohorts, including small cell malignancies of extrapulmonary origin. Eligibility criteria included disease progression during standard treatment in the 6 months before study enrollment. Patients were enrolled from February 2017 to February 2019. The primary endpoint was the proportion of patients alive without progression at 27 weeks. Response to pembrolizumab was evaluated every 9 weeks (3 cycles) with radiographic imaging.

RESULTS

Seven women with gynecologic extrapulmonary small cell carcinoma were enrolled, 6 with cervical and 1 with vulvar carcinoma. No patient was progression free at 27 weeks. At first radiologic assessment, 1 patient had stable disease, while 6 had progression. The single patient with stable disease at 6 weeks had disease progression at 14 weeks. The median progression-free interval was 2.1 months (range 0.8-3.3 months). Severe treatment-related adverse events (≥grade 3) were seen in 2 of 7 patients (29%); 1 patient had grade 3 asymptomatic elevation of serum alkaline phosphatase, and 1 had grade 3 asymptomatic elevation of serum alanine aminotransferase.

CONCLUSIONS

Pembrolizumab alone showed minimal activity in women with recurrent small cell neuroendocrine tumors of the lower genital tract. Treatment was well tolerated in the majority of study participants, and the rate of severe adverse events was low.

Abstract 3011: Phase I study of TT-00420, a multiple kinase inhibitor, in patients with triple negative breast cancers and other advanced solid tumors

Background: TT-00420, a multikinase inhibitor, targets cell proliferation, angiogenesis, and immunomodulatory pathways by inhibiting the mitotic kinases Aurora A/B, Janus kinases (JAK) involved in cytokine signalling, and receptor tyrosine kinases involved in angiogenesis (FGFRs and VEGFRs). These pathways are important in the pathogenesis of triple negative breast cancer (TNBC) and TT-00420 has shown preclinical efficacy against multiple subtypes of TNBC.

Methods: This phase I, open-label, first-in-human study is enrolling adult patients with advanced or metastatic TNBC and other advanced solid tumors. The study contains a dose escalation phase (N=22), followed by dose expansion in two parallel cohorts, a TNBC cohort (N=22) and a selected advanced tumor (SAT) cohort (N=22). The provisional dose range for dose escalation is 1 mg/d to 20 mg/d. Dose escalation is guided by Bayesian modeling with overdose control until a dose recommended for dose expansion is determined. Adverse events (AE) are evaluated per CTCAE v5.0 criteria, and tumor response is evaluated per RECIST v1.1 criteria. Patients receive a single daily oral administration of TT-00420 continuously for 28-day cycles. The primary endpoint is to evaluate dose limiting toxicity (DLT) and identify a maximum tolerated dose (MTD). Secondary objectives include evaluating the efficacy and pharmacokinetic profile of TT-00420.

Results: As of the data cut-off date on September 26, 2019, 11 patients have received TT-00420 treatment in 4 dose levels, 1 mg/d (N=1), 3 mg/d (N=1), 5 mg/d (N=3), and 8 mg/d (N=6). No DLTs have been observed at any of the tested dose levels. Commonly reported suspected AEs across all tested dose levels were grades 1 or 2 diarrhea (n=4, 36.4%), myalgia (n=2, 18.2%) and hypertension (n=2, 18.2%). Two suspected serious adverse events reported were grade 2 hypertension (8 mg/d) and grade 3 nausea (5 mg/d). No grade 3 AEs have occurred in more than one subject. Stable disease has been observed in 4 patients, including a metastatic TNBC patient treated at 8 mg/d, who received 9 lines of prior antineoplastic therapy. Per RECIST v1.1 criteria, this TNBC patient had a 21% decrease in target lesions observed on restaging after two cycles of TT-00420 treatment. Interestingly, significant clinical improvement in the skin lesions were observed as well. More detailed data from this TNBC patient and other patients treated in the study will be presented. Enrollment in dose escalation is currently ongoing. Clinical trial information: NCT03654547

Citation Format: Sarina A. Piha-Paul, Ecaterina Ileana-Dumbrava, Filip Janku, Daniel D. Karp, Funda Meric-Bernstam, Jordi Rodon, Brenda Ngo, Peng Peng, Frank Wu. Phase I study of TT-00420, a multiple kinase inhibitor, in patients with triple negative breast cancers and other advanced solid tumors [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3011.

Investigating the disparate enrollment of older adults on phase I clinical trials: Evolving participation patterns of patients 65 years and older w advanced cancer on phase I trials

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Background: While safety and dose-finding remain the primary objective of Phase 1 trials, the potential for clinical benefit has taken a greater meaning in the last decade with the novel therapies. With data from phase I trials being submitted for regulatory approval, the finer details of these studies are under even more scrutiny: in particular, do the trial participants reflect the general patient population for whom the drug may be indicated? To that end, we investigated age-based enrollment on phase I clinical trials over time. Methods: We queried a prospectively maintained database at a major phase I trials center to identify eligible patients and demographic + clinical variables including phase I trial characteristics, age at date of enrollment into 3 age-based cohorts: AYA ages 15-39y, mid-age 40-64y, older adults aged 65y+. We calculated descriptive statistics, and explored correlations (Pearson/Spearman) and associations (linear regression) between age and independent variables. Results: Over a 3-year period (1/1/17 to 12/31/19), we identified 6267 pts enrolled on 338 phase I trials. Median overall age 58.4y (range 15.5-95.1y). 729 (12%, median age 34.8y) were AYA, 3652 (58%, median age 55.4y) mid-age and 1886 (30%, median 70y) older adults, of whom 870 pts were aged 70-79y and 76 pts aged 80y+ (18 being >85y). There was no association b/w senior participation and year of enrollment (2017 31%, 2018 29%, 2019 30%, b/w age and type of therapy (i.e. targeted vs immunotherapy, etc.) or b/w age and # of drugs given on trial (single agent vs combo) (all p > 0.05). Conclusions: Older adults remain underrepresented on phase I trials esp. when compared to incidence of cancer in that age group (30% enrollment vs 60% incidence), a discordance more staggering in the oldest old pts (85y+; only 18 pts enrolled over 3 yrs when compared to 140,690 pts 85y+ w a new cancer dx in just 2019). Once enrolled, older adults received similar types of phase I therapies with comparable number of drugs as compared to middle age patients, i.e. older adults were just as likely to get immunotherapy or targeted therapy as well mono- vs combo therapy as mid-age pts. [Table: see text]

Patient-reported out-of-pocket costs and financial toxicity during early-phase oncology clinical trials

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Background: Clinical trials are an important therapeutic option for cancer patients (pts). Although financial burden in cancer treatment is well-documented, the financial burden associated with clinical trials is not well understood, especially for pts with lower income. Methods: We conducted a survey regarding economic burden and financial toxicity in cancer pts who had been on Phase I clinical trials for ≥1 month. Financial Toxicity Score (FTS) was assessed using the validated COmprehensive Score for Financial Toxicity (COST) survey (scale 0-44, lower scores indicate worse toxicity). Pts also reported monthly out-of-pocket (OOP) medical and non-medical expenses. We applied multivariable logistic regression to analyze risk of financial toxicity, and unanticipated expenses. Results: Early-phase clinical trial pts (N = 213, median age = 59y; 59% female; 74% White, 45% w/ annual income ≤$60K; 50% lived > 300 miles from the clinic; 40% required air travel; 37% had Medicare, 54% had employer sponsored insurance) had a median FTS of 20, with interquartile range of 12. Median monthly OOP costs for non-medical expenses was $1075, and for medical expenses was $475. Median total monthly OOP costs was $1750. 55% and 64% of pts reported that actual medical and non-medical expenses were higher than expected, respectively. Worse financial toxicity (≤ median FTS) in pts was associated with yearly household income < $60K (OR: 2.7, P = 0.008), having medical costs higher than expected (OR: 3.2, P = 0.024), participation on ≥1 Phase I clinical trial prior to their current trial (OR: 2.2, P = 0.028), and living > 100 miles away from the clinical trials hospital (OR: 2.3, P = 0.043). However, 34% of pts who lived > 100 miles away received partial/full reimbursement of clinical trial-related travel costs from study sponsor/other/insurance. Racial/ethnic minority (OR: 2.6, P = 0.008) and pts who were unemployed or not working outside the home (OR: 2.4, P = 0.023) were more likely to report that actual medical costs were much higher than expected. 53% of pts used savings and 18% retirement accounts to pay for treatment. Conclusions: Among cancer pts participating on clinical trials, economic burden is high, and most of pts’ OOP costs were on non-medical expenses. Financial toxicity is disproportionally higher in pts with lower income. OOP costs can be substantial and are often unexpected for pts. Furthermore, prior participation in ≥1 Phase I clinical trial and living far away from the clinical trials hospital seem to increase risk of financial toxicity.

Genomically informed longitudinal monitoring of circulating tumor DNA (ctDNA) to predict outcomes of cancer therapy

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Background: Short fragments of ctDNA can be detected and quantified from blood samples of patients with cancer. We hypothesize that dynamic changes in quantity of ctDNA in patients with advanced solid cancers during the first few weeks of therapy can predict treatment outcomes reported by standard imaging. Methods: We enrolled patients with advanced cancers treated with experimental therapies, who had blood collection for ctDNA isolation and testing at baseline, mid-cycle and at the time of restaging imaging. Patients who were treated with multiple treatment lines were included with separate record for each therapy. Genomically informed molecular testing of ctDNA was performed using unamplified droplet digital PCR (QX200, Bio-Rad) designed based on known molecular profile of tumor tissue and ctDNA was quantified as aggregate variant allele frequency (VAF%) for detected molecular aberrations. Patients were classified based on results of their first restaging imaging as responders (complete [CR] or partial response [PR]) vs. non-responders (stable disease [SD], progressive disease [PD]) and progressors (PD) vs. non-progressors (CR, PR, SD). Results: Total of 85 patients who received 132 courses of therapies between May 2012 and June 2019 were analyzed. Breast (N = 21), melanoma (N = 14) and cholangiocarcinoma (N = 14) were most frequent tumor types. Aggregate VAF at mid-cycle was higher in non-responders (3.98%) compared to responders (0.40%, P = 0.016) and in progressors (4.40%) compared to non-progressors (2.10%, P = 0.019) as measured by 5% trimmed mean. Similarly, aggregate VAFs at first imaging restaging was higher in non-responders (5.10%) compared to responders (0.10%, P = 0.001) and in progressors (10.80%) compared to non-progressors (0.90%, P < 0.001). Progressors demonstrated increase in ctDNA VAF at the time of the first imaging restaging compared to decrease in non-progressors (0.7% vs. -4%, P = 0.015). In addition, increase in ctDNA VAF at the first imaging restaging was associated with more PD (44% vs. 8%, P = 0.019) and less PR/CR (0% vs. 31%, P < 0.001). Median time-to-treatment failure was shorter in patients with increase in ctDNA VAF at the time of the first imaging restaging (52 days vs. 89 days, P = 0.002). Conclusions: Dynamic changes in quantity of blood-derived ctDNA within the first few weeks of therapy correspond with treatment outcomes reported by the first restaging imaging and time-to-treatment failure.

PT-112 in advanced metastatic castrate-resistant prostate cancer (mCRPC), as monotherapy or in combination with PD-L1 inhibitor avelumab: Findings from two phase I studies

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Background: PT-112, the first pyrophosphate conjugate in Phase I/II clinical development, induces robust immunogenic cell death and is osteotropic, prompting study in mCRPC during Phase I. We report safety and efficacy findings in the mCRPC sub-population given PT-112 monotherapy (NCT02266745) or in combination with avelumab (“PAVE”) (NCT03409458, ongoing). Methods: Patients (pts) received PT-112 days 1, 8, 15 of a 28d cycle; pts on the PAVE combination also received 800 mg avelumab days 1 and 15; all enrolled during dose escalation or at PT-112 doses previously deemed safe. Pts on therapy (Tx) for ≥2 cycles or who stopped Tx due to progressive disease or treatment-related adverse events (TRAEs) were evaluated for exploratory efficacy. Results: 10 pts on PT-112 (200-420 mg/m2) and 18 pts on PAVE (150-200 mg/m2 PT-112) were evaluable for safety. The most common PT-112 TRAEs were thrombocytopenia (70%, grade (Gr) ≤3) and fatigue (40%, Gr ≤2) with mono-Tx; nausea (50%, Gr ≤2) and fatigue (39%, Gr ≤2) with PAVE. Mono-Tx pts had 6.5 median prior lines of Tx; 2/7 pts with measurable disease (MD) had reductions in target lesions; prostate specific antigen (PSA) declined in 3/10 pts, 1 with ≥50% reduction; and serum alkaline phosphatase (ALP) reductions were seen in 9/10 pts. PAVE pts had 5.5 median prior lines of Tx; radiographic reductions were seen in 2/9 pts with MD; PSA declined in 6/14 pts, 3 with ≥50% decrease, with 1 responder progression free 11.3 months (microsatellite stable). An additional response is ongoing at 4 mos, with 93% PSA decrease and 48% reduction in target lesions (PIK3CBmut & PTEN loss). 13/14 pts with bone metastases had ALP reductions. Pain improvement, opioid cessation and improved performance status were noted in both cohorts. Conclusions: PT-112 was well-tolerated with evidence of efficacy in mCRPC as mono-Tx and in combination with avelumab in heavily pre-treated pts. Bone pain improvement and nearly universal observation of ALP reduction suggest marked therapeutic activity of PT-112 in bone metastases. Serologic / RECIST responses and prolonged disease control in multiple pts substantiate further development of PT-112 in mCRPC. Clinical trial information: NCT02266745, NCT03409458.

Abstract P1-19-18: Everolimus, letrozole and trastuzumab in hormone receptor-positive, HER2-positive/amplified or mutant metastatic cancer: Evaluating synergy and overcoming resistance

Background: Combinations of HER2 and aromatase or mTOR inhibitors demonstrated activity in the clinical setting. We hypothesized that the triple combination of HER2 targeted therapy, aromatase and mTOR inhibitor has increased anticancer activity.

Methods: We designed a 3+3 dose escalation phase I study of the aromatase inhibitor letrozole 2.5mg PO daily, mTOR inhibitor everolimus 2.5-10mg PO daily and HER2 antibody trastuzumab 4-8mg loading dose followed by 2-4mg maintenance dose IV on day 1 of 21-day cycle in patients with hormone-receptor positive, HER2-positive/amplified or mutant advanced cancers (confirmed by immunohistochemistry and/or FISH and/or next-generation sequencing) with preplanned expansion cohort at for patients with metastatic breast cancer to determine maximum tolerated dose (MTD) and/or recommended phase 2 dose (RP2D), dose limiting toxicities (DLT), overall safety and response (NCT02152943).

Results: A total of 32 patients (men, 1; women, 31; HER2 amplification, 28; HER2 mutation, 4; breast cancer, 26; other cancers, 6), median age 55.5 years, median of 5 prior therapies (including letrozole [13] or other aromatase inhibitor [10]; everolimus [3]; trastuzumab [25] or other HER2 targeted therapy [2]) were enrolled in the planned 6 dose levels. The MTD has not been reached and letrozole 2.5mg PO daily, everolimus 10mg PO daily and trastuzumab 8mg loading dose followed by 4mg maintenance dose IV on day 1 of 21-day cycle was declared as RP2D. DLTs included grade 3 (G3) mucositis (1 patient) at dose level 3, and G3 thrombocytopenia, neutropenia (1 patient) at dose level 4. Other G3 or G4 treatment-related toxicities included G4 hyperglycemia in 1 patient, G3 hyperglycemia in 3 patients, G4 anemia in 1 patient, G3 anemia in 2 patients, G3 thrombocytopenia in 1 patient, G3 transaminitis in 1 patient, G3 mucositis in 1 patient and G3 headache in 1 patient. Of 32 patients, 5 (16%) had a partial response (all with heavily-pretreated breast cancer with HER2 amplification [4] or HER2A775_G776insYVMA mutation [1]), 23 (72%) stable disease (SD) including 5 (16%) patients with SD &gt; 12 months (all with heavily-pretreated breast cancer) and 4 (13%) progressed. The median change in size of target lesions per RECIST 1.1. was -5% (-91% to +47%). Median time to treatment failure (TTF) was 4.3 months (95% CI 0.0-9.6). A total of 14 patients had serial plasma collection to assess dynamics of circulating tumor DNA and clonal evolution and the data will be presented at the meeting.

Conclusions: The combination of letrozole, everolimus and trastuzumab is well tolerated with encouraging activity in heavily-pretreated patients with HER2-amplified or mutant advanced breast cancer.

Citation Format: Alexej Ballhausen, Jennifer J Wheler, Daniel D Karp, Sarina A Piha-Paul, Siqing Fu, Shubham Pant, Apostolia M Tsimberidou, David S Hong, Vivek Subbiah, Veronica R Holley, Helen J Huang, Abeena M Brewster, Kimberly H Koenig, Nuhad K Ibrahim, Funda Meric-Bernstam, Filip Janku. Everolimus, letrozole and trastuzumab in hormone receptor-positive, HER2-positive/amplified or mutant metastatic cancer: Evaluating synergy and overcoming resistance [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P1-19-18.

Radiomics to predict response to pembrolizumab in patients with advanced rare cancers

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Background: To predict responders versus non-responders to Pembrolizumab, an anti PD-1 monoclonal antibody, in patients with advanced rare cancers. Methods: The study included 58 patients with advanced rare cancers (eg. squamous cell carcinoma of the skin, adrenocortical carcinoma, carcinoma of unknown primary, and paraganglioma) who were enrolled in a phase 2 trial of Pembrolizumab. Tumor response was evaluated using Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. Patients were categorized into: 21 responders (stable disease, partial response, and complete response) and 37 non-Responders (progressive disease). Target lesion(s) obtain from standard-of-care, pre-treatment contrast enhanced CT scans were segmented using 3D slicer v4.8.1. A total of 610 features (10 histogram-based and 600 second-order texture features) were calculated from each extracted volume of interest (VOI). Radiomic features were obtained using a feature selection approach based on Least Absolute Shrinkage and Selection Operator (LASSO). Selected features were used to build a classification model, using XGboost, for prediction of tumor response to Pembrolizumab. To evaluate the robustness of the estimates, Leave-One-Out Cross-Validation (LOOCV) was performed. Results: A total of 10 radiomic features were selected; the XGboost-based classification robustly differentiated between responders vs non-responders (area under the curve, sensitivity and specificity were 99%, 100%, and 95%, respectively [p<0.0001]). Conclusions: Our radiomic derived features were able to identify imaging differences that can evaluate patients’ response to Pembrolizumab treatment.

Out-of-pocket costs and financial toxicity experienced by patients in early-phase clinical trials

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Background: Clinical trials are an important therapeutic option for cancer patients. Although financial burden in cancer treatment is well-described, the financial burden associated with clinical trials is not well understood, especially for patients with lower socioeconomic status. Methods: We conducted a survey regarding economic burden and financial toxicity among cancer patients on Phase I clinical trials for at least 1 month. Financial Toxicity Score (FTS) was assessed using the validated COmprehensive Score for Financial Toxicity (COST) survey (scale 0-44, lower scores indicating worse financial toxicity). Patients also reported monthly out of pocket (OOP) medical and non-medical expenses. Results: Of 147 consecutive patients approached, 105 agreed to participate; median age = 60y; 62% female; 49% had annual income < $60K; 50% lived < 300 miles from the clinic; 34% required air travel; 41% had Medicare, 50% had employer sponsored insurance. Median FTS = 20, with interquartile range of 12.5. Median monthly OOP costs for non-medical expenses was $985, and for medical expenses was $475. Median total monthly OOP costs was $1695. Compared to patients in the highest quartile of FTS, a significantly lower % of patients in the lowest (worst) quartile of FTS had incomes > $60K (27% v. 77%, P < 0.001), and a significantly higher % were unemployed or not working outside the home (54% v. 12%, P = 0.001), and incurred higher than expected medical (39% vs. 12%, P = 0.025) and non-medical (64% vs. 15%, P = 0.003) expenses. Compared with patients for whom medical costs were not much higher than expected, a significantly higher % of patients with medical costs much higher than expected were non-White (77% v. 46%, P = 0.004) and unemployed/not working outside the home (46% v. 19%, P = 0.009). Conclusions: Among cancer patients participating on clinical trials, economic burden is high and financial toxicity is disproportionally higher in patients with lower income. OOP costs can be substantial and are often unexpected for patients.

Phase II clinical trial of pembrolizumab efficacy and safety in advanced adrenocortical carcinoma

Background

Adrenocortical carcinoma (ACC) is a rare malignancy without good treatment options. There are limited data about the use of immunotherapy in ACC. We investigated the efficacy and safety of pembrolizumab in patients with metastatic ACC.

Methods

This is a pre-specified cohort of a single-center, investigator-initiated, phase II clinical trial using pembrolizumab monotherapy in patients with rare malignancies. Patients must have had prior treatment fail in the past 6 months before study enrollment. Patients were enrolled from August 2016 to October 2018. Follow-up data were updated as of March 26, 2019.

Patients received 200 mg pembrolizumab intravenously every 3 weeks without concomitant oncologic therapy. The primary endpoint was non-progression rate (NPR) at 27 weeks. Other endpoints included adverse events, tumor responses measured independently by objective radiologic criteria, and select immunological markers.

Results

Sixteen patients with ACC (including eight women [50%]) were included in this cohort. Ten patients (63%) had evidence of hormonal overproduction (seven had cortisol-producing ACC). Non-progression rate at 27 weeks was evaluable in 14 patients, one patient was lost to follow-up, and one patient left the study because of an adverse event. Five of 14 patients were alive and progression-free at 27 weeks (non-progression rate at 27 weeks was 36, 95% confidence interval 13–65%). Of the 14 patients evaluable for imaging response by immune-related Response Evaluation Criteria in Solid Tumors, two had a partial response (including one with cortisol-producing ACC), seven had stable disease (including three with cortisol-producing ACC), and five had progressive disease, representing an objective response rate of 14% (95% confidence interval 2–43%). Of those who had stable disease, six had disease stabilization that lasted ≥4 months. Severe treatment-related adverse events (≥grade 3) were seen in 2 of 16 patients (13%) and resulted in one patient discontinuing study participation. All studied tumor specimens (14/14) were negative for programmed cell death ligand-1 expression. Thirteen of 14 tumor specimens (93%) were microsatellite-stable. Eight of 14 patients (57%) had a high tumor-infiltrating lymphocyte score on immunohistochemistry staining.

Conclusions

Single-agent pembrolizumab has modest efficacy as a salvage therapy in ACC regardless of the tumor’s hormonal function, microsatellite instability status, or programmed cell death ligand-1 status. Treatment was well tolerated in most study participants, with a low rate of severe adverse events.

Trial registration

ClinicalTrials.gov identifier: NCT02721732, Registered March 29, 2016.

Phase I trial of IACS-010759 (IACS), a potent, selective inhibitor of complex I of the mitochondrial electron transport chain, in patients (pts) with advanced solid tumors

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Background: A subset of tumors possess genetic or microenvironmental alterations that render cells dependent on mitochondria oxidative phosphorylation (OXPHOS) for survival. IACS, a potent oral selective inhibitor of mitochondrial complex I, showed robust responses in multiple preclinical tumor models, providing strong rationale for clinical testing. Methods: Pts with advanced cancers received IACS in increasing dose levels (DL) using 3+3 dose escalation. 7-day QD induction of IACS was followed by maintenance weekly (QW) or twice weekly (BIW) dosing. Phamacokinetics (PK), lactate and pH were assessed serially. Paired tumor biopsies were assessed for pharmacodynamic and predictive biomarkers. Results: 18 pts were treated; M/F 16/2; ECOG PS 0/1: 3/15. Mean age 49 (23-69) yrs. Tumors comprised advanced colorectal (n = 4), castration resistant prostate cancer (CRPC) (n = 3), pancreatic (n = 2), other cancers (n = 9). DL1: 2mg QD 7 days induction/0.5mg QW maintenance (n = 3); DL2: 2.5mg QD 7 days/1mg QW (n = 3); DL3: 3mg QD 7 days/3mg QW (n = 3); DL4: 2.5mg QD 7 days/2.5mg BIW (n = 4); DL5: 2mg QD 7 days/2mg BIW (n = 5). IACS was well tolerated with 12 (67%) pts reporting G1-2 IACS related toxicities, such as raised lactate (n = 10), nausea (n = 8), fatigue (n = 7), vomiting (n = 5), myalgia (n = 4) and peripheral neuropathy (n = 4). 1 pt in DL3 and 2 pts in DL4 had ≥G3 IACS related toxicities, such as nausea (n = 2), vomiting (n = 1), raised lactate (n = 1), dehydration (n = 1), visual changes (n = 1), and peripheral neuropathy (n = 1). Raised lactate was not associated with acidosis. DL5 is now being expanded to assess the maximum tolerated dose (MTD). PK showed good oral bioavailability, with long T1/2 and low intrapatient variability. Cmax = 14nM on Day 7 at the end of DL5 induction phase, confirming biologically active doses. 7 pts had best response of RECIST stable disease. A pt with heavily pretreated CRPC achieved RECIST partial response with resolution of CRPC related pain. Conclusions: IACS is well tolerated with preliminary evidence of antitumor activity. MTD expansions include CRPC, TNBC, pancreatic cancer and molecularly selected (ENO1 loss; SMARCA4 mutation) tumor cohorts. Clinical trial information: NCT03291938.

Out of pocket costs and financial toxicity experienced by patients in early phase clinical trials

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Background: Clinical trials are an important therapeutic option for cancer patients. Although financial burden in cancer treatment is well-described, the financial burden associated with clinical trials is not well understood, especially for patients with lower socioeconomic status. Methods: We conducted a survey regarding economic burden and financial toxicity among cancer patients on Phase I clinical trials for at least 1 month. Financial Toxicity Score (FTS) was assessed using the validated COmprehensive Score for Financial Toxicity (COST) survey (scale 0-44, lower scores indicating worse financial toxicity). Patients also reported monthly out of pocket (OOP) medical and non-medical expenses. Results: Of 147 consecutive patients approached, 105 agreed to participate; median age = 60y; 62% female; 49% had annual income < $60K; 50% lived < 300 miles from the clinic; 34% required air travel; 41% had Medicare, 50% had employer sponsored insurance. Median FTS = 20, with interquartile range of 12.5. Median monthly OOP costs for non-medical expenses was $985, and for medical expenses was $475. Median total monthly OOP costs was $1695. Compared to patients in the highest quartile of FTS, a significantly lower % of patients in the lowest (worst) quartile of FTS had incomes > $60K (27% v. 77%, P < 0.001), and a significantly higher % were unemployed or not working outside the home (54% v. 12%, P = 0.001), and incurred higher than expected medical (39% vs. 12%, P = 0.025) and non-medical (64% vs. 15%, P = 0.003) expenses. Compared with patients for whom medical costs were not much higher than expected, a significantly higher % of patients with medical costs much higher than expected were non-White (77% v. 46%, P = 0.004) and unemployed/not working outside the home (46% v. 19%, P = 0.009). Conclusions: Among cancer patients participating on clinical trials, economic burden is high and financial toxicity is disproportionally higher in patients with lower income. OOP costs can be substantial and are often unexpected for patients.

Baseline cfDNA characteristics and evolution of cfDNA profile during treatment with selective FGFR inhibitor TAS-120

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Background: There is an increasing role for cfDNA in monitoring response and mechanisms of resistance. We performed cfDNA analysis in a subset of patients enrolled on a Phase I trial with an irreversible, selective FGFR1-4 inhibitor, TAS-120. Methods: 58 plasma samples from 17 patients (13 with cholangiocarcinoma) were analyzed on a 73-gene, next-generation sequencing panel. Selected patients(pts) had longitudinal samples. Results: At least one alteration was detected in 46 cfDNA samples, in 16 (94%) of 17 pts – a pt with GBM had no alterations detected. 14 pts had alterations in FGFR2/3 by genomic testing of archival tumor samples, comprising 20 total alterations (18 unique). 10 of 20 FGFR2/3 alterations were also detected by cfDNA testing: 4/5 SNVs, 1/2 amplifications, 5/13 fusions. Three pts had FGFR/FGF alterations not included (thus not detected) in the cfDNA panel: 2 with FGF ligand amplification, and one FGFR4 mutation. 6 pts (35%) had PR, 5 (29%) had SD and 6 (35%) PD as a best response to TAS-120. Four pts had prior FGFRi: 2 had a PR, 1 SD, and 1 PD on TAS-120. Baseline cfDNA mutations became undetectable during treatment in 4/6 pts with PR. 4 of 6 PD pts had other driver mutations at baseline including mutations in PIK3CA, KRAS, IDH1, BRCA2, or amplifications in PIK3CA, PDGFR. 9 pts with cfDNA available at progression after SD/PR: 3 had acquired FGFR2 mutations (one each of V564L, V564F, or N549K). Two also acquired alterations in other candidate resistance genes ( PTEN and MAP2K1). Another pt had low variant allele frequency (VAF) NRAS G12D and BRAF A694T pretreatment and had SD. At progression, cfDNA revealed an increase in NRAS VAF and mutations acquired in the MAPK pathway . One pt with prior FGFRi acquired FGFR2 V564I and V564K detected by cfDNA prior to initiation of TAS-120, and had a PR on TAS-120. There was a drop in FGFR2 V564I VAF with response that subsequently increased with progression. The patient also acquired a FGFR2 V564L mutation at progression. Conclusions: FGFR alterations can be detected by cfDNA. cfDNA may detect potential resistance mechanisms, including PI3K or MAPK pathway alterations and acquired FGFR2 mutations. Patients with gatekeeper mutations in cfDNA at baseline may still respond to TAS-120. Further study is needed to determine the impact of FGFR2 mutations and co-alterations on TAS-120 sensitivity.

A phase Ib study of prexasertib, a checkpoint kinase (CHK1) inhibitor, and LY3023414, a dual inhibitor of class I phosphatidylinositol 3-kinase (PI3K) and the mammalian target of rapamycin (mTOR) in patients with advanced solid tumors

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Background: Prexasertib inhibits CHK1, a kinase involved in DNA repair and replication. LY3023414 inhibits PI3K/mTOR signaling, implicated in the development of malignant disease. Prexasertib + LY3023414 has resulted in enhanced antitumor activity in triple negative breast cancer (TNBC) in vitro models. Methods: This Phase 1b study in patients (pts) with solid tumors assessed escalating doses of prexasertib (60-105 mg/m2 IV every 14 days [q14d]) and LY3023414 (100-200 mg orally twice daily [BID]). Dose escalation ceased once the maximum tolerated dose of each monotherapy was reached. An initial expansion cohort (Arm E) explored prexasertib 105 mg/m2 q14d + LY3023414 200 mg BID. Subsequent expansion cohorts evaluated prexasertib 105 mg/m2 q14d + LY3023414 150 mg BID in pts with solid tumors with PIK3CA mutations (Arm E2) or TNBC (Arm E3). Results: Fifty pts were enrolled (escalation: n = 13; Arm E: n = 9; Arm E2: n = 15; Arm E3: n = 13). No dose-limiting toxicities (DLTs) were observed during escalation however DLT-equivalent toxicities were observed in 2 pts in Arm E (anemia, neutropenia, thrombocytopenia, oral mucositis, abdominal pain, fatigue). Due to toxicity, a reduced dose of LY3023414 (150 mg BID) was assessed in Arm E2/E3. In the 28 patients treated in Arms E2/E3, common treatment-related adverse events (any grade; grade ≥3) were: leukopenia/neutropenia (82%; 79%), thrombocytopenia (46%; 36%), nausea (46%; 0%), stomatitis (39%, 4%), vomiting (36%; 0%), and anemia (29%; 18%). Febrile neutropenia was reported in 25% of pts. Dose reductions in Arm E2/E3 were common. In escalation, 2 pts achieved a partial response (PR) and 3 pts achieved stable disease (SD). In Arm E, 78% of pts achieved SD. Of the pts evaluable at the time of data transfer, PRs were achieved in 1 pt with an unknown primary (Arm E2) and 2 pts with TNBC (Arm E3). Each agent’s pharmacokinetic profile was consistent with prior monotherapy data. Conclusions: Prexasertib + LY3023414 showed preliminary efficacy in heavily pretreated pts with solid tumors but was associated with toxicity, suggesting supportive care may be required. Clinical trial information: NCT02124148.

Cancer-Related Internet Use and Its Association With Patient Decision Making and Trust in Physicians Among Patients in an Early Drug Development Clinic: A Questionnaire-Based Cross-Sectional Observational Study

Background

The role of cancer-related internet use on the patient-physician relationship has not been adequately explored among patients who are cancer-related internet users (CIUs) in early-phase clinical trial clinics.

Objective

We examined the association between cancer-related internet use and the patient-physician relationship and decision making among CIUs in an early drug development clinic.

Methods

Of 291 Phase I clinic patients who completed a questionnaire on internet use, 179 were CIUs. Generations were defined by the year of patient’s birth: “millennials” (after 1990) and “Generation X/Y” (1965-1990) grouped as “Millennials or Generation X/Y”; “Baby Boomers” (1946-1964); and “Greatest or Silent Generation” (1945 and earlier). Statistical analyses included the Wilcoxon matched-pairs signed-rank test and the Mann-Whitney U test.

Results

CIUs were 52% (94/179) female, 44% (78/179) were older than 60 years, and 60% (108/179) had household incomes exceeding US $60,000. The sources of information on cancer and clinical trials included physicians (171/179, 96%), the internet (159/179, 89%), and other clinical trial personnel (121/179, 68%). For the overall sample and each generation, the median values for trust in referring and Phase I clinical trial physicians among early drug development clinic CIUs were 5 on a 0-5 scale, with 5 indicating “complete trust.” CIUs’ trust in their referring (5) and phase 1 (5) physicians was higher than CIUs’ trust in Web-based cancer-related information (3; P<.001 for both). CIUs who reported visiting the National Cancer Institute (NCI) website, NCI.org, to learn about cancer reported higher levels of trust in Web-based cancer-related information than CIUs who did not use the NCI website (P=.02). Approximately half of CIUs discussed internet information with their doctor. Only 14% (23/165) of CIUs had asked their physician to recommend cancer-related websites, and 24% (35/144) of CIUs reported at least occasional conflict between their physician’s advice and Web-based information.

Conclusions

Despite the plethora of websites related to cancer and cancer clinical trials, patients in early-phase clinical trial settings trust their physicians more than Web-based information. Cancer-related organizations should provide regularly updated links to trustworthy websites with cancer and clinical trial information for patients and providers and educate providers on reliable cancer websites so that they can better direct their patients to appropriate internet content.

Phase 1 study of the combination of vemurafenib, carboplatin, and paclitaxel in patients with BRAF-mutated melanoma and other advanced malignancies

BACKGROUND

BRAF inhibitors are effective against selected BRAFV600 -mutated tumors. Preclinical data suggest that BRAF inhibition in conjunction with chemotherapy has increased therapeutic activity.

METHODS

Patients with advanced cancers and BRAF mutations were enrolled into a dose-escalation study (3+3 design) to determine the maximum tolerated dose (MTD) and dose-limiting toxicities (DLTs).

RESULTS

Nineteen patients with advanced cancers and BRAF mutations were enrolled and received vemurafenib (480-720 mg orally twice a day), carboplatin (area under the curve [AUC] 5-6 intravenously every 3 weeks), and paclitaxel (100-135 mg/m2 intravenously every 3 weeks). The MTD was not reached, and vemurafenib at 720 mg twice a day, carboplatin at AUC 5, and paclitaxel at 135 mg/m2 were the last safe dose levels. DLTs included a persistent grade 2 creatinine elevation (n = 1), grade 3 transaminitis (n = 1), and grade 4 thrombocytopenia (n = 1). Non-dose-limiting toxicities that were grade 3 or higher and occurred in more than 2 patients included grade 3/4 neutropenia (n = 5), grade 3/4 thrombocytopenia (n = 5), grade 3 fatigue (n = 4), and grade 3 anemia (n = 3). Of the 19 patients, 5 (26%; all with melanoma) had a partial response (PR; n = 4) or complete response (CR; n = 1); these responses were mostly durable and lasted 3.1 to 54.1 months. Of the 13 patients previously treated with BRAF and/or mitogen-activated protein kinase kinase (MEK) inhibitors, 4 (31%) had a CR (n = 1) or PR (n = 3). Patients not treated with prior platinum therapy had a higher response rate than those who did (45% vs 0%; P = .045).

CONCLUSIONS

The combination of vemurafenib, carboplatin, and paclitaxel is well tolerated and demonstrates encouraging activity, predominantly in patients with advanced melanoma and BRAFV600 mutations, regardless of prior treatment with BRAF and/or MEK inhibitors.

Phase I Study of the BRAF Inhibitor Vemurafenib in Combination With the Mammalian Target of Rapamycin Inhibitor Everolimus in Patients With BRAF-Mutated Malignancies

Purpose

Parallel activation of the phosphatidylinositol 3-kinase-mammalian target of rapamycin pathway represents a mechanism of primary and acquired resistance to BRAF-targeted therapy, but the two pathways have yet to be cotargeted in humans. We performed a phase I study to evaluate the safety and activity of the BRAF inhibitor vemurafenib in combination with the mammalian target of rapamycin inhibitor everolimus in BRAF-mutated advanced solid tumors.

Patients and Methods

We performed a 3+3 dose-escalation study with escalating doses of both oral (PO) vemurafenib administered twice a day and PO everolimus administered daily.

Results

Twenty patients with advanced cancers were enrolled. The median adult age was 64 years (range, 17 to 85 years); two pediatric patients were 10 and 13 years old. Patients were heavily pretreated with prior BRAF or MEK inhibitors (n = 11), phase I clinical trial therapy (n = 10), surgery (n = 18), radiation therapy (n = 11), and chemotherapy (n=13). One of the two pediatric patients initially experienced grade 3 rash, but after dermatologic intervention, the patient remains on trial with partial response and no dose reduction at time of analysis. Four dose-limiting toxicities (rash, n = 1; fatigue, n = 3) were observed at dose level 2. Therefore, dose level 1 (vemurafenib 720 mg PO twice a day and everolimus 5 mg PO daily) was the maximum-tolerated dose. Overall, four patients (22%) had a partial response and nine patients (50%) had stable disease as best response. One pediatric patient with pleomorphic xanthroastrocytoma remains on protocol with continued clinical response after 38 cycles.

Conclusion

The combination of vemurafenib 720 mg PO twice a day and everolimus 5 mg PO daily is safe and well tolerated and has activity across histologies, with partial responses noted in advanced non-small-cell lung cancer, melanoma, optic nerve glioma, and xanthroastrocytoma, including patients who previously experienced progression on BRAF and/or MEK inhibitor therapy. Further investigation in a larger cohort of molecularly matched patients is warranted.

A phase I clinical trial of hepatic arterial infusion of oxaliplatin and oral capecitabine, with or without intravenous bevacizumab, in patients with advanced cancer and predominant liver involvement

BACKGROUND

We investigated hepatic arterial infusion (HAI) oxaliplatin combined with capecitabine +/- bevacizumab in advanced cancer with predominant liver involvement.

METHODS

Patients received HAI oxaliplatin (140 mg/m²) and escalating doses of capecitabine (500, 750, and 1000 mg/m²), with (Group 1) or without (Group 2) bevacizumab (10 mg/kg IV). A 3 + 3 dose design was used, followed by an expansion phase.

RESULTS

From 9/2009 to 2/2014, 61 patients (34 men, 27 women) were enrolled (Group 1 = 44; Group 2 = 17). Patients were treated in Group 2 if they had contraindications to bevacizumab (n = 13) or if there was no opening in Group 1 (n = 4). The median age was 60 years (range, 20-88). The most common cancers were colorectal (22 patients), liver (12), pancreatic (7), breast (4), and biliary tract (4). The median number of prior therapies was 3 (range, 1-12); 32 (53%) patients had received oxaliplatin. The dose-limiting toxicity was Grade 3 diarrhea and occurred in 2 patients receiving 1000 mg/m² capecitabine. The maximum tolerated dose was HAI oxaliplatin 140 mg/m², capecitabine 750 mg/m², and bevacizumab 10 mg/kg. The most common toxicities were nausea/vomiting, anemia, thrombocytopenia, neutropenia, and hypomagnesemia. The rates of partial response and stable disease ≥ 4 months were 22% and 39% (Group 1) and 9% and 0% (Group 2). The respective median time to treatment failure and overall survival were 3 and 6.9 months (Group 1) and 1.5 and 5.9 months (Group 2).

CONCLUSION

HAI oxaliplatin combined with capecitabine +/- bevacizumab was well-tolerated and was associated with favorable outcomes in selected patients.

Prevalence of MDM2 amplification and coalterations in 523 advanced cancer patients in the MD Anderson phase 1 clinic

Background

TP53 is the most commonly mutated gene in cancer and codes for the best studied tumor suppressor, p53. MDM2 is involved in the negative regulation of p53 and itself serves as an oncogene, reported to be overexpressed in several cancer tumor types. In this retrospective study, we assessed the occurrence of MDM2 amplification among patients with various types of cancers and its association with clinical factors, other genetic aberrations, and response to targeted therapy in a phase I clinical trial setting.

Methods

Samples from patients with advanced solid tumors who had been referred to the MD Anderson phase I clinical trials program between January 2011 and January 2016 were collected and analyzed for MDM2 amplification using FoundationOne's genomic profiling assay. Patients whose tumors expressed MDM2 amplification were compared to those with tumors of the same histologic types without MDM2 amplification.

Results

We tested tumors from 523 patients, of which 23 (4.4%) had MDM2 amplification. The highest prevalence of MDM2 amplification was in sarcoma (57%), breast cancer (13%) and bladder cancer (9%). Six patients with liposarcoma were treated on phase I protocol with an MDM2 inhibitor. The most common molecular aberrations co-occurring with MDM2 amplification was CDK4 amplification (70%). TP53 mutation was also detected in 7 patients (30%).

Conclusion

MDM2 amplification was most commonly associated with liposarcoma. Concomitant alterations in additional genes such as CDK4 amplification and TP53 mutations, along with variable responses to targeted therapies including MDM2 inhibitors, suggest that further combinational studies are needed to target this population.

Comparative Effectiveness of an mTOR-Based Systemic Therapy Regimen in Advanced, Metaplastic and Nonmetaplastic Triple-Negative Breast Cancer

BACKGROUND

Triple-negative breast cancer (TNBC) is a heterogeneous disease with subtypes having different "targetable" molecular aberrations. Metaplastic breast cancers (MpBCs) are typically TNBCs and commonly have alterations in the PI3K/Akt/mTOR pathway. We previously reported efficacy for an mTOR-based chemotherapy regimen in MpBC. To determine if tumor subtype influences prognosis, we compared treatment outcomes of patients with MpBC with those of patients with nonmetaplastic TNBC receiving an mTOR-based systemic therapy regimen.

PATIENTS AND METHODS

Patients with advanced MpBC and nonmetaplastic TNBC were treated at our institution from April 16, 2009, through November 4, 2014, using mTOR inhibition (temsirolimus or everolimus) with liposomal doxorubicin and bevacizumab (DAT/DAE). Median progression-free survival (PFS) and overall survival (OS) were estimated by the Kaplan-Meier method. Cox regression analyses were used to evaluate associations between tumor histology and outcomes. Multivariable models were adjusted for all covariates.

RESULTS

Fourteen patients with nonmetaplastic TNBC and 59 patients with advanced MpBC were treated with DAT/DAE. MpBC patients were older (p = .002) and less likely to have a history of bevacizumab use (p = .023). Median PFS for the nonmetaplastic TNBC and MpBC patients was 2.5 months and 4.8 months, respectively. This difference in PFS was statistically significant on univariable (p = .006) but not multivariable analysis (p = .087). Median OS for the nonmetaplastic TNBC and MpBC patients was 3.7 months and 10.0 months, respectively (p = .0003). MpBC remained significantly associated with improved OS on multivariable analysis (p < .0001).

CONCLUSION

In our study, DAT/DAE appeared to be more effective in MpBC compared with nonmetaplastic TNBC. These data support patient selection for targeted therapy in TNBC.

IMPLICATIONS FOR PRACTICE

Metaplastic breast cancers (MpBCs) represent <1% of all breast cancers, demonstrate mesenchymal differentiation, and are typically resistant to chemotherapy. Patients with advanced MpBC treated with an mTOR-based systemic therapy regimen had better long-term outcomes compared with patients with nonmetaplastic triple-negative breast cancer treated with the same regimen, suggesting that metaplastic histology may predict benefit from agents targeting the PI3K/Akt/mTOR pathway.