CD200 is overexpressed in the pancreatic tumor microenvironment and predictive of overall survival

Pancreatic cancer is an aggressive disease with a 5 year survival rate of 13%. This poor survival is attributed, in part, to limited and ineffective treatments for patients with metastatic disease, highlighting a need to identify molecular drivers of pancreatic cancer to target for more effective treatment. CD200 is a glycoprotein that interacts with the receptor CD200R and elicits an immunosuppressive response. Overexpression of CD200 has been associated with differential outcomes, depending on the tumor type. In the context of pancreatic cancer, we have previously reported that CD200 is expressed in the pancreatic tumor microenvironment (TME), and that targeting CD200 in murine tumor models reduces tumor burden. We hypothesized that CD200 is overexpressed on tumor and stromal populations in the pancreatic TME and that circulating levels of soluble CD200 (sCD200) have prognostic value for overall survival. We discovered that CD200 was overexpressed on immune, stromal, and tumor populations in the pancreatic TME. Particularly, single-cell RNA-sequencing indicated that CD200 was upregulated on inflammatory cancer-associated fibroblasts. Cytometry by time of flight analysis of PBMCs indicated that CD200 was overexpressed on innate immune populations, including monocytes, dendritic cells, and monocytic myeloid-derived suppressor cells. High sCD200 levels in plasma correlated with significantly worse overall and progression-free survival. Additionally, sCD200 correlated with the ratio of circulating matrix metalloproteinase (MMP) 3: tissue inhibitor of metalloproteinase (TIMP) 3 and MMP11/TIMP3. This study highlights the importance of CD200 expression in pancreatic cancer and provides the rationale for designing novel therapeutic strategies that target this protein.

Intracystic injection of large surface area microparticle paclitaxel for chemoablation of intraductal papillary mucinous neoplasms: Insights from an expanded access protocol

AIMS

A novel large surface area microparticle paclitaxel (LSAM-PTX) has unique properties of long retention in cystic spaces while maintaining high drug concentration. We prospectively evaluated the safety and response of EUS-guided fine needle injection (EUS-FNI) of LSAM-PTX to chemoablate branch duct (BD)-IPMNs.

METHODS

Subjects diagnosed with BD-IPMNs exhibiting at least one worrisome criteria and considered non-surgical were enrolled in a multicenter clinical trial (NCT03188991) and subsequently included in an Expanded Access Protocol (EAP) where they received EUS-FNI of LSAM-PTX (15 mg/mL).

RESULTS

Six BD-IPMNs measuring (mean ± SD) 3.18 ± 0.76 cm in diameter among 5 subjects (mean age: 66 years) were treated by EUS-FNI of LSAM-PTX. A mean of 4 doses of LSAM-PTX (mean dose/cyst: 73 ± 31 mg) were administered, and subjects were followed for up to 32 months. The mean volume reduction/cyst ranged from 42 to 89% (9.58 ± 5.1 ml to 2.2 ± 1.1 ml (p = 0.016)). The mean surface area reduction ranged from 31 to 83% (21.9 ± 8.7 cm2 to 5.7 ± 2.5 cm2 (p = 0.009)). Higher dosing-frequency of EUS-FNI of LSAM-PTX significantly correlated with a reduction in cyst volume (R2 = 0.87, p = 0.03) and surface area (R2 = 0.83, p = 0.04). Comparing pre- and post-ablation samples, molecular analysis of the cyst fluid revealed a loss of IPMN-associated mutations in 5 cases (83.3%), while reemergence was observed in 1 case and persistence in 1 case. Intracystic changes (fibrosis/calcification) were observed in 83.3% (n = 5). One subject developed mild acute pancreatitis (1 of 22 EUS-FNIs of LSAM-PTX).

CONCLUSION

In this EAP, EUS-FNI of LSAM-PTX into BD-IPMNs was safe and resulted in volume and surface area reduction, morphological changes, and loss of pathogenic mutations.

Phase Ib study of HSP90 inhibitor, onalespib (AT13387), in combination with paclitaxel in patients with advanced triple-negative breast cancer

Background

Heat shock protein 90 (HSP90) is a molecular chaperone required for stabilization of client proteins over-activated in triple-negative breast cancer (TNBC). Over-expression of HSP90 client proteins has been implicated in paclitaxel resistance. Onalespib (AT13387) is a potent inhibitor of HSP90 that could improve paclitaxel efficacy when administered in combination.

Design

This phase Ib trial administered onalespib with paclitaxel in patients with advanced TNBC to assess safety and establish a recommended phase II dose (RP2D).

Objectives

The primary objectives were determining the dose-limiting toxicities and maximum tolerated dose of combination therapy. Secondary objectives included pharmacokinetic (PK) analysis and determination of overall response rate (ORR), duration of response (DOR), and progression-free survival (PFS).

Methods

Patients with advanced TNBC were treated with standard dose intravenous paclitaxel in combination with intravenous onalespib at doses ranging from 120 to 260 mg/m2 administered on days 1, 8, and 15 of a 28-day cycle using a standard 3 + 3 design. A total of 15 patients were enrolled to dose expansion cohort at RP2D to confirm safety profile.

Results

Thirty-one patients were enrolled in the study, of which over 90% had received prior taxane therapy. Paclitaxel was given for metastatic disease in 23% of patients. Adverse events (AEs) included anemia (grade 3: 20%), lymphopenia (grade 3: 17%), and neutropenia (grade 3: 33%, grade 4: 4%). The most frequent grade ⩾3 non-hematologic AE was diarrhea (7%). The established RP2D was 260 mg/m2 onalespib when given with paclitaxel at 80 mg/m2. PK analysis revealed a modest drug interaction profile for onalespib in the combination regimen. ORR was 20%. Three patients achieved complete responses, all of whom had received prior taxane therapy. Median DOR was 5.6 months; median PFS was 2.9 months.

Conclusion

Combination treatment with onalespib and paclitaxel had an acceptable toxicity profile and RP2D was determined to be 260 mg/m2 of onalespib. Combination therapy showed antitumor activity in patients with advanced TNBC.

Trial registration

Onalespib and paclitaxel in treating patients with advanced TNBC https://clinicaltrials.gov/ct2/show/NCT02474173.

Inflamed but not impulsive: Acute inflammatory cytokine response does not impact prepotent response inhibition

BACKGROUND

Prior evidence has linked inflammation with impulsivity, but most of this evidence is cross-sectional. In this study, we provoked an acute inflammatory cytokine response to see whether it lowered prepotent response inhibition on three cognitive tasks.

METHOD

This study features secondary analyses from a randomized crossover trial in which 171 postmenopausal breast cancer survivors (Stage I-IIIA) each received a typhoid capsular polysaccharide vaccination and a saline placebo injection in a random sequence at two separate visits at least one month apart. Participants completed the Stroop Color-Discrepant Task, the 2-back, and the Conners Continuous Performance Test (CPT) on the computer between 5 and 7 h after the injections. They had their blood drawn once before and repeatedly after the injection to measure interleukin-1 receptor antagonist and interleukin-6 responses.

RESULTS

Women committed marginally fewer errors on the Stroop color-discrepant trials after the typhoid vaccine (M = 0.36, SE = 0.08), compared to placebo (M = 0.54, SE = 0.09, p = .076). Injection type did not predict 2-back accuracy (p = .80) or CPT commission errors (p = .47). Inflammatory cytokine responses were also unrelated to the outcomes of interest (ps>.16).

CONCLUSION

We found no evidence that an acute inflammatory cytokine response provokes response disinhibition - an important facet of impulsivity. In fact, our only marginally non-significant result suggested that women were better able to inhibit their prepotent responses on the Stroop after receiving the typhoid vaccine, compared to placebo. Further experimental tests of the acute inflammatory cytokine response's effect on other aspects of impulsivity are warranted.

LIMITATIONS

The sample was female, primarily White, highly educated cancer survivors, and recruitment was not premised on impulsive traits or diagnosis with an impulsive-related disorder. Also, there are many facets of impulsivity, and this study only measured response inhibition.

Worry and Mindfulness Differentially Impact Symptom Burden Following Treatment Among Breast Cancer Survivors: Findings From a Randomized Crossover Trial

BACKGROUND

Breast cancer survivors often experience many somatic and cognitive side effects resulting from their cancer diagnosis and treatment, including higher rates of pain, fatigue, and memory/concentration problems. Emotion regulation offers opportunities to either enhance or dampen physical health.

PURPOSE

In a secondary analysis of a double-blind randomized controlled trial (RCT) using a typhoid vaccine to assess factors associated with breast cancer survivors' inflammatory responses, we assessed how two specific aspects of emotion regulation, mindfulness, and worry, corresponded to acute changes in focus problems, memory problems, and fatigue along with performance on pain sensitivity and cognitive tasks across two visits among breast cancer survivors.

METHODS

Breast cancer survivors (N = 149) completed two 8.5-hr visits at a clinical research center. Survivors were randomized to either the vaccine/saline placebo or a placebo/vaccine sequence. Worry and mindfulness questionnaires provided data on trait-level emotion regulation abilities. Fatigue, memory problems, and focus difficulties were assessed via Likert scales six times-once before the injections and then every 90 min for 7.5 hr thereafter. Women also completed a pain sensitivity task and several cognitive tasks at each visit.

RESULTS

Findings from this study showed that breast cancer survivors who worried more and were less mindful experienced subjective memory problems, focus problems, and cold pain sensitivity across two visits and irrespective of injection type. Lower mindfulness also corresponded to higher subjective fatigue and hot pain sensitivity and objective ratings. Emotion regulation skills did not predict objective pain sensitivity or cognitive problems.

CONCLUSION

Results from this study highlight the benefits of adaptive emotion regulation in helping mitigate symptoms associated with breast cancer survivorship.

Latent class symptom profiles of colorectal cancer survivors with cancer-related cognitive impairment

PURPOSE

Colorectal cancer (CRC) survivors experience cancer-related cognitive impairment and co-occurring symptoms after cancer treatments. There has been little data to inform the risk factors of complex symptom phenotypes in CRC survivors.

OBJECTIVES

To determine if subgroups of CRC survivors after cancer treatments could be identified based on the cognitive impairment and common co-occurring symptoms (depression, anxiety, sleep disturbance, fatigue, and pain); and to explore risk factors (sociodemographic and clinical characteristics, perceived stress, and social support) of these subgroups.

METHODS

Latent class profile analysis (LCPA) was used to identify subgroups based on self-reported symptoms in 64 CRC survivors. Cognitive impairment was measured by assessing subjective cognitive function using the Patient-Reported Outcome Measurement Information System (PROMIS) measure. The Kruskal-Wallis test and regression analyses were performed.

RESULTS

Three distinct latent classes were identified (Class 1: All Low '28.1%'; Class 2: High Psychological Symptoms (depression/anxiety) '25%'; Class 3: High Somatic Symptoms (fatigue, sleep disturbance, and pain) with High Cognitive Impairment'46.9%'). The pain was the most distinguishable symptom across the latent classes. The high symptom burden group was associated with less time since cancer diagnosis, higher perceived stress levels, and poor emotional social support.

CONCLUSION

Our study adds to the information on interindividual variability in symptom experience of CRC survivors with cognitive impairment. Findings suggest a need for increased attention to screening for co-occurring symptoms (e.g., high pain) and future interventions focused on stress management and social support.

Depression, Inflammation, and Intestinal Permeability: Associations with Subjective and Objective Cognitive Functioning throughout Breast Cancer Survivorship

About one-in-three breast cancer survivors have lingering cognitive complaints and objective cognitive impairment. Chronic inflammation and intestinal permeability (i.e., leaky gut), two risk factors for cognitive decline, can also fuel depression-another vulnerability for cognitive decline. The current study tested whether depression accompanied by high levels of inflammation or intestinal permeability predicted lower subjective and objective cognitive function in breast cancer survivors. We combined data from four breast cancer survivor studies (n = 613); some had repeated measurements for a total of 1015 study visits. All participants had a blood draw to obtain baseline measures of lipopolysaccharide binding protein-a measure of intestinal permeability, as well as three inflammatory markers that were incorporated into an inflammatory index: C-reactive protein, interleukin-6, and tumor necrosis factor-α. They reported depressive symptoms on the Center for Epidemiological Studies depression scale (CES-D), and a binary variable indicated clinically significant depressive symptoms (CES-D ≥ 16). The Kohli (749 observations) and the Breast Cancer Prevention Trial (591 observations) scales assessed subjective cognitive function. Objective cognitive function tests included the trail-making test, Hopkins verbal learning test, Conners continuous performance test, n-back test, FAS test, and animal-naming test (239-246 observations). Adjusting for education, age, BMI, cancer treatment type, time since treatment, study visit, and fatigue, women who had clinically elevated depressive symptoms accompanied by heightened inflammation or intestinal permeability reported poorer focus and marginally poorer memory. However, poorer performance across objective cognitive measures was not specific to inflammation-associated depression. Rather, there was some evidence of lower verbal fluency; poorer attention, verbal learning and memory, and working memory; and difficulties with visuospatial search among depressed survivors, regardless of inflammation. By themselves, inflammation and intestinal permeability less consistently predicted subjective or objective cognitive function. Breast cancer survivors with clinically significant depressive symptoms accompanied by either elevated inflammation or intestinal permeability may perceive greater cognitive difficulty, even though depression-related objective cognitive deficits may not be specific to inflammation- or leaky-gut-associated depression.

Conflicts hurt: social stress predicts elevated pain and sadness after mild inflammatory increases

ABSTRACT

Individuals respond differently to inflammation. Pain, sadness, and fatigue are common correlates of inflammation among breast cancer survivors. Stress may predict response intensity. This study tested whether breast cancer survivors with greater exposure to acute or chronic social or nonsocial stress had larger increases in pain, sadness, and fatigue during an acute inflammatory response. In total, 156 postmenopausal breast cancer survivors (ages 36-78 years, stage I-IIIA, 1-9 years posttreatment) were randomized to either a typhoid vaccine/saline placebo or the placebo/vaccine sequence, which they received at 2 separate visits at least 1 month apart. Survivors had their blood drawn every 90 minutes for the next 8 hours postinjection to assess levels of interleukin-6 and interleukin-1 receptor antagonist (IL-1Ra). Shortly after each blood draw, they rated their current levels of pain, sadness, and fatigue. Women also completed the Test of Negative Social Exchange to assess chronic social stress and the Trier Inventory of Chronic Stressors screen to index chronic general stress. At each visit, a trained experimenter administered the Daily Inventory of Stressful Events to assess social and nonsocial stress exposure within the past 24 hours. After statistical adjustment for relevant demographic and behavioral covariates, the most consistent results were that survivors who reported more chronic social stress reported more pain and sadness in response to IL-1Ra increases. Frequent and ongoing social stress may sensitize the nervous system to the effects of inflammation, with potential implications for chronic pain and depression risk among breast cancer survivors.

Risk Factors of Health-Related Quality of Life among Gastrointestinal Cancer Survivors in the U.S.: With a Focus on Social and Behavioral Determinants of Health (SBDH)

BACKGROUND

Increasing numbers of long-term gastrointestinal (GI) cancer survivors highlight the importance of understanding the factors contributing to their health-related quality of life (HRQoL). We investigated the risk factors of HRQoL, including demographics, clinical characteristics, and social and behavioral determinants of health (SBDH).

METHODS

Data on adult GI cancer survivors (n = 3201) from the Behavioral Risk Factors Surveillance System (BRFSS) surveys from 2014-2021 (except for 2015) were analyzed. Unadjusted/adjusted logistic regression was used.

RESULTS

The majority were women (54%) and white (78%), with a median age of 67. Survivors who were 65 years or older, diagnosed with colorectal cancer, or who had fewer comorbidities were more likely to report significantly better HRQoL. Significant social factors of poor HRQoL included unmarried, racial and ethnic minorities, poor socioeconomic status, and poor healthcare access. Significant behavioral factors of poor HRQoL were lack of physical activity, heavy alcohol consumption, and current smoking, with lack of physical activity being the most significant factor.

CONCLUSIONS

The SBDH has a critical role in HRQoL. Future studies are warranted to develop a tailored survivorship intervention, such as physical rehabilitation, and to explore machine learning/artificial intelligence-based predictive models to identify cancer survivors at a high risk of developing poor HRQoL.

Real-World Use of Immunotherapy for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the third most common cause of cancer-related mortality worldwide and accounts for 90% of all primary liver cancers. Chronic inflammation is the hallmark across most prevalent etiologies among which HBV is the leading cause worldwide (33%), followed by alcohol (30%), HCV (21%), other factors like non-alcoholic steatohepatitis linked to insulin resistance/metabolic syndrome, and obesity associated inflammation (16%). Deregulation of the tightly controlled immunological network leads to liver disease, including chronic infection, autoimmunity, and tumor development. While inflammation drives oncogenesis in the liver, HCC also recruits ICOS+ FOXP3+ Tregs and MDSCs and upregulates immune checkpoints to induce a state of immunosuppression in the tumor microenvironment. As such, research is focused on targeting and modulating the immune system to treat HCC. The Checkmate 040 and Keynote 224 studies established the role of immunotherapy in the treatment of patients with HCC. In Phase I and II trials, nivolumab and pembrolizumab demonstrated durable response rates of 15-20% and were subsequently approved as second-line agents after sorafenib. Due to the success of the IMbrave 150 and HIMALAYA trials, which examined the combination of atezolizumab/bevacizumab and tremelimumab/durvalumab, respectively, the FDA approved these regimens as first-time treatment options for patients with advanced HCC. The encouraging results of immunotherapy in the management of HCC has led researchers to evaluate if combination with locoregional therapies may result in a synergistic effect. Real-world studies represent an invaluable tool to assess and verify the applicability of clinical trials in the bedside setting with a more varied patient population. We herein review current real-life use of ICIs in the management of HCC and highlight some of the ongoing clinical trials that are expected to change current recommended first-line treatment in the near future.

Distress Disorder Histories Relate to Greater Physical Symptoms Among Breast Cancer Patients and Survivors: Findings Across the Cancer Trajectory

BACKGROUND

Psychological disorders can substantially worsen physical symptoms associated with breast cancer diagnosis and treatment, reducing survivors' quality of life and increasing recurrence risk. Distress disorders may be particularly detrimental given their physical correlates. Across two studies, we examined the relationship between a distress disorder history and physical symptoms pre- and post-adjuvant treatment - two important periods of the cancer trajectory.

METHODS

Breast cancer patients awaiting adjuvant treatment (n = 147; mean age = 52.54) in study 1 and survivors 1-10 years post-treatment (n = 183; mean age = 56.11) in study 2 completed a diagnostic interview assessing lifetime presence of psychological disorders. They also rated their pain, fatigue, physical functioning, and self-rated health. Covariates included body mass index, age, cancer stage, menopause status, and physical comorbidities.

RESULTS

Results from both studies indicated that a distress disorder history was associated with higher pain, fatigue, and sleep difficulties as well as lower self-rated health compared to those without such a history.

CONCLUSIONS

These findings suggest that breast cancer survivors with a distress disorder may be particularly at risk for more physical symptoms, poorer sleep, and worse self-rated health both prior to and following adjuvant treatment.

First-in-human study of oleclumab, a potent, selective anti-CD73 monoclonal antibody, alone or in combination with durvalumab in patients with advanced solid tumors

BACKGROUND

CD73 upregulation in tumors leads to local immunosuppression. This phase I, first-in-human study evaluated oleclumab (MEDI9447), an anti-CD73 human IgG1λ monoclonal antibody, alone or with durvalumab in patients with advanced colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDAC), or epidermal growth factor receptor-mutant non-small-cell lung cancer (NSCLC).

METHODS

Patients received oleclumab 5-40 mg/kg (dose-escalation) or 40 mg/kg (dose-expansion) intravenously every 2 weeks (Q2W), alone (escalation only) or with durvalumab 10 mg/kg intravenously Q2W.

RESULTS

192 patients were enrolled, 66 during escalation and 126 (42 CRC, 42 PDAC, 42 NSCLC) during expansion. No dose-limiting toxicities occurred during escalation. In the monotherapy and combination therapy escalation cohorts, treatment-related adverse events (TRAEs) occurred in 55 and 54%, respectively, the most common being fatigue (17 and 25%). In the CRC, PDAC, and NSCLC expansion cohorts, 60, 57, and 45% of patients had TRAEs, respectively; the most common were fatigue (15%), diarrhea (9%), and rash (7%). Free soluble CD73 and CD73 expression on peripheral T cells and tumor cells showed sustained decreases, accompanied by reduced CD73 enzymatic activity in tumor cells. Objective response rate during escalation was 0%. Response rates in the CRC, PDAC, and NSCLC expansion cohorts were 2.4% (1 complete response [CR]), 4.8% (1 CR, 1 partial response [PR]), and 9.5% (4 PRs), respectively; 6-month progression-free survival rates were 5.4, 13.2, and 16.0%.

CONCLUSIONS

Oleclumab ± durvalumab had a manageable safety profile, with pharmacodynamic activity reflecting oleclumab's mechanism of action. Evidence of antitumor activity was observed in tumor types that are generally immunotherapy resistant.

CLINICAL TRIAL REGISTRATION

Clinicaltrials.gov, NCT02503774; date of registration, July 17, 2015.

NRG/RTOG 1112: Randomized phase III study of sorafenib vs. stereotactic body radiation therapy (SBRT) followed by sorafenib in hepatocellular carcinoma (HCC)

489

Background: To determine if SBRT followed by sorafenib (SBRT/S) improves overall survival (OS), progression free survival (PFS) and quality of life (QOL) vs. sorafenib alone (S), in patients (pts) with HCC. Methods: Eligible pts had new or recurrent HCC, unsuitable for surgery, ablation or TACE, with Zubrod performance status (PS) 0-2, Child-Pugh (CP) A, BCLC stage B or C, ≤ 5 HCCs, sum of hepatic HCCs ≤ 20 cm, and distant metastases ≤ 3 cm. Pts were randomized 1:1 to S 400 mg BID vs. SBRT (27.5-50 Gy in 5 fractions) followed by S 200 mg BID, increased to 400 mg BID after 28 days. Primary endpoint was OS; reported secondary endpoints - PFS, adverse events (AEs - CTCAEv4), and QOL (improvement in FACT-Hep score by ≥ 5 points from baseline to 6 months). Planned sample size was 292 pts (238 OS events, HR=0.72, 80% power, 1-sided α=0.05). Accrual closed early, due to a change in HCC standard of care. Statistics were amended to report as of 7/1/2022, projecting 155 OS events, with 65% power and the same α. OS and PFS were estimated by Kaplan-Meier and arms compared using log-rank test. Cox proportional hazards models were used to analyze treatment effect. Secondary endpoints were tested with 2-sided α=0.05. Results: Of 193 pts accrued from April 2013 to March 2021 from 23 sites, 177 eligible pts were randomized to S (n=92) vs. SBRT/S (n=85). Median age was 66 yrs (27-84); 41% had Hep. C; 19% had Hep. B or B/C. 82% were BCLC stage C. 74% had macrovascular invasion (MVI), 63% with VP3 or VP4 MVI. 4% had metastases. Median sum of max diameter of HCCs was 8.2 cm for S and 6.7 cm for SBRT/S; 40% had a single HCC. Median follow-up for all and alive pts was 13.2 and 33.7 mo. 22% of S pts received SBRT after discontinuing S. With 153 OS events, median OS was improved from 12.3 mo. (90% CI 10.6, 14.3) with S to 15.8 mo. (90% CI 11.4-19.2) with SBRT/S (HR=0.77, 1-sided p=0.0554). After adjusting for PS, M stage, CP A5 vs. 6, and degree of MVI, OS was statistically significantly improved for SBRT/S (HR=0.72, 95% CI 0.52-0.99, 2-sided Cox p=0.042). Median PFS was improved from 5.5 mo. (95% CI 3.4-6.3) with S to 9.2 months (95% CI 7.5-11.9) with SBRT/S (HR=0.55, 95% CI 0.40-0.75, 2-sided p=0.0001). 8 grade (G) 3+ bleeds were seen: 5 in S arm (1 G3 variceal, 2 G3 upper GI, 1 G3 hepatic, and 1 G4 abdominal) and 3 post SBRT/S (2 G3 upper GI, 1 G3 lower GI). Treatment-related G3+ AEs were not significantly different (S - 42%; SBRT/S - 47%; p=0.52), with 3 G5 AEs (S - 1 hepatic failure, 1 death NOS; SBRT/S - 1 lung infection). 83 (47%) pts consented to QoL. Of 20 S and 17 SBRT/S pts with QoL assessments at baseline and 6 months, 10% on S improved in FACT-Hep score vs 35% on SBRT/S. Conclusions: Compared to S alone, SBRT improved OS & PFS in patients with HCC, with no observed increase in AEs, and a strong suggestion for QOL benefit at 6 months. Supported by U10CA180868 (NRG Onc. Op., U10CA180822 (NRG Onc. SDMC), UG1CA189867 (NCORP), and U24CA180803 (IROC) from the NCI. Clinical trial information: NCT01730937 .

BXQ-350 may alleviate symptoms of chemotherapy- induced peripheral neuropathy via modulation of S1P

93

Background: Chemotherapy Induced Peripheral Neuropathy (CIPN) is a debilitating side effect associated with many chemotherapeutic agents. It significantly impacts quality of life during treatment, causes lasting neuropathy, and may also shorten the treatment regimen, potentially impacting clinical benefit. The pathology of CIPN is still not completely understood, however, increasing evidence suggests sphingosine-1-phosphate (S1P) may be an important signaling molecule. Altered neuronal sphingolipid metabolism has been linked to neuropathic pain, evidenced by elevated plasma levels of S1P in patients receiving chemotherapy. Methods: BXQ-350 is a nanovesicle of Saposin C, an allosteric activator of sphingolipid metabolism, that lowers systemic S1P. BXQ-350 was investigated in an adult Phase 1 dose-escalation safety study in heavily pretreated all-comer cancer patients with advanced solid malignancies ( NCT02859857 ). The primary objective was to determine the safety profile and potential clinical activity of BXQ-350 as monotherapy. Samples were collected to explore potential biomarkers. Results: BXQ-350 was safe and well tolerated. Clinical signs of activity were observed in 13 patients (~17.8% of evaluable patients) experiencing a clinical benefit (PR, SD) up to cycle 6 and beyond including: 4 CRC, 1 pancreatic, and 1 GIST patient. Two patients are still on study six years after enrollment, including 1 CRC. Interestingly, a pancreatic cancer patient with chronic CIPN at time of enrollment spontaneously reported a significant improvement of her neuropathic symptoms shortly after receiving BXQ-350. Investigation of potential improvements in patients with chronic CIPN at time of enrollment revealed that 4 out of 10 patients experienced an improvement of their symptoms that seemed to be associated with a decrease in S1P systemic levels following BXQ-350 administration. BXQ-350 was subsequently investigated in a murine oxaliplatin-CIPN preclinical model with results showing a dose-dependent prevention/resolution of CIPN correlating with decreasing systemic S1P levels. Conclusions: Results of this Phase 1 study in heavily pretreated patients shows that BXQ-350 was well tolerated and seems to generate a clinical benefit via modulation of S1P. There were preliminary signs that BXQ-350 may alleviate symptoms of CIPN in relation to decreasing S1P concentration. Additional studies are underway to better understand this novel mechanism of action. Clinical trial information: 02859857 .

BXQ-350: Modulating ceramide and sphingosine-1-phosphate for antitumor activity in patients with advanced CRC

154

Background: Sphingolipids are a class of bioactive signaling molecules implicated in multiple cellular processes and molecular pathways. Many publications have demonstrated that ceramides are proapoptotic, synergize with cancer treatments, and mitigate chemoresistance. Findings also demonstrated that sphingosine-1-phosphate (S1P) is a key sphingolipid that promotes cancer cell proliferation, activates multiple oncogenic pathways, and stimulates immuno-suppressor cell populations promoting a pro-tumoral microenvironment. Several studies of colorectal cancer patients have shown high levels of ceramides being associated with improved survival, while high S1P levels are associated with a poor prognosis. Hence, modulation of sphingolipid metabolism continues to be a promising treatment approach. Methods: BXQ-350 is a nanovesicle of Saposin C, an allosteric activator of sphingolipid metabolism, that lowers systemic S1P and increases C18 ceramide. BXQ-350 was investigated in a Phase 1 dose-escalation safety study in an all-comer cancer patients with advanced solid malignancies ( NCT02859857 ) to determine its safety profile and potential clinical activity as monotherapy. Samples were collected to explore potential biomarkers. Results: 13 patients (~17.8% of evaluable patients) had a clinical benefit up to cycle 6 (PR, SD), with the majority experiencing a decrease in systemic S1P levels and an increase in C18 levels. 8 patients (~11% of evaluable patients) had PFS > 6 months, with 2 patients still on study six years after enrollment. Analysis of plasma samples also revealed an increase in anti-tumoral cytokines (IFNg, TNFa, IL-2) and a decrease in pro-tumoral ones (IL-6, 8, 10). Among patients with PFS > 6 months, there were 4 recurrent CRC patients (1PR, 3SD): 1 patient had a PFS of ~12 months, 2 of ~18 months, and 1 is still on study after 6 years. Conclusions: Results of this Phase 1 study in heavily pretreated patients show BXQ-350 was well tolerated and seem to generate a clinical benefit in CRC patients via modulation of S1P and ceramides. A phase 2 trial of BXQ-350 in combination with FOLFOX/Bevacizumab in newly diagnosed mCRC is on-going with plans to further investigate this novel mechanism of action. Clinical trial information: 02859857 .

Breast cancer survivors' typhoid vaccine responses: Chemotherapy, obesity, and fitness make a difference

PURPOSE

To investigate breast cancer survivors' inflammatory responses to typhoid vaccine as a window into their innate immune response to novel pathogens.

METHODS

This double-blind crossover trial randomized 158 breast cancer survivors to either the vaccine/saline placebo or the placebo/vaccine sequence. The relative contributions of age, cardiorespiratory fitness (VO_2peak), type of cancer treatment, central obesity, and depression to interleukin (IL)-6, IL-1 receptor antagonist (IL-1Ra), and WBC vaccine responses were assessed pre-injection and 1.5, 3, 4.5, 6, and 7.5 h post-injection.

RESULTS

The vaccine produced larger IL-6, IL-1Ra, and WBC responses than placebo, ps < 0.0001. Prior chemotherapy, higher central obesity, and lower VO_2peak were associated with smaller vaccine responses after controlling for baseline inflammation. Vaccine response was summarized by the percent increase in area under the curve (IL-6, WBC) or average post-injection mean (IL-1Ra) for vaccine relative to placebo. Women who received chemotherapy had smaller vaccine responses than women who did not for both IL-6 (44% vs 78%, p <.001) and WBC (26% vs 40%, p <.001); IL-1ra response was not significantly moderated by chemotherapy. Women whose central adiposity was one standard deviation above the mean had smaller vaccine responses than women with average adiposity for IL-6 (33% vs 54%, p <.001), WBC (20% vs 30%, p <.001), and IL-1Ra (2.0% vs 3.2%, p <.001). Women with an average level of VO_2peak had smaller vaccine responses than women whose VO_2peak was one standard deviation above the mean for IL-6 (54% vs 73%, p <.001), WBC (30% vs 40%, p <.001), and IL-1Ra (3.2% vs. 4.1%, p = 0.01). Age and depression did not significantly moderate vaccine responses.

CONCLUSIONS

This study provided novel data on chemotherapy's longer-term adverse immune consequences. The data also have an important public health message: even relatively low levels of fitness can benefit the innate immune response to a vaccine.

A phase 1, safety and dose escalation study of BXQ-350, a nanovesicle formulation of saposin c, a modulator of sphingolipid metabolism, in patients with advanced solid malignancies

e15059

Background: Bexion recently completed an all-comer Phase 1 clinical study of BXQ-350 in patients with advanced solid tumors including high grade gliomas to evaluate the safety profile and to determine the maximum tolerated- or biologically effective dose. BXQ-350 is a nanovesicle comprised of recombinantly expressed Saposin C (SapC) and dioleoylphosphatidylserine. SapC, a human protein encoded by the Psap gene, is an allosteric activator of several enzymes involved sphingolipid metabolism. Sphingolipids are bioactive signaling molecules implicated in multiple cellular processes including apoptosis and immune stimulation/inhibition. In nonclinical studies, BXQ-350 evidences broad anticancer activity, selectively inducing apoptosis of cancer cells by modulating sphingolipids (ceramides/S1P), and BXQ-350 acts synergistically with multiple classes of anticancer agents and treatments. Methods: In the trial (NTC02859857), performed at four US sites, BXQ-350 was administered intravenously for a minimum of 6 cycles over 28 weeks at escalating doses from 0.7 mg/kg up to 2.4 mg/kg. Multiple secondary parameters were included to characterize its pharmacokinetics, efficacy profile and identify potential biomarkers. Results: Results indicate that: i) BXQ-350 was safe and well-tolerated as no DLT was observed and an MTD was not reached; ii) treatment related adverse events leading to discontinuation were typical for this patient population and disease related; iii)* biomarker analyses suggest positive modulation of sphingolipid metabolism and stimulation of the immune system; iv)* surprisingly, some patients noted improvement of existing peripheral neuropathies. RANO or RECIST ver 1.1 criteria were used to evaluate tumor response: 13 patients reached Cycle 6 restaging (17% ORR); 8 patients (11.0% of evaluable patients) demonstrated progression free survival over more than 6 months; and 2 patients (a GBM and CRC patient) are still on study after 5 years. * subject of separate abstracts. Conclusions: In conclusion, BXQ-350 is a first-in-human and first-in-class novel biologic whose Phase 1 results suggest that it may have clinical utility either as a monotherapy or when combined with other targeted agents. Clinical trial information: 028559857.

The impact of HRD in patients with pancreatic adenocarcinoma undergoing surgical resection: An updated analysis

4132

Background: Limited data is available regarding which mutations in the homologous recombination repair (HRR) pathway beyond BRCA can be targeted with platinum-based chemotherapy in the perioperative setting in patients with pancreatic ductal adenocarcinoma (PDAC). In this updated analysis, we assess the outcome of patients with homologous recombination deficiency (HRD) in response to platinum vs. non-platinum based perioperative chemotherapy in resected PDAC and have included additional variants linked to HRD. Methods: Patients with resectable PDAC, diagnosed between 1999-2020 from the participating members of the Oncology Research Information Exchange Network (ORIEN) were included in the study. Patient’s germline and somatic whole exome sequencing (WES) data were analyzed for known pathogenic and likely pathogenic variants according to ClinVar for the following HRR pathway genes: BRCA1, BRCA2, PALB2, BRIP1, BRAD1, BLM, BAP1, ATM, RAD51C, RAD51, RAD50, RAD54B, CHECK2, NBN, FANCA/B/C/D2/E/F/G, ARID1A, MRE11 and XRCC2. The Kaplan Meier method was used to compare median overall survival (mOS) between patients with and without HRR pathway mutations in response to perioperative platinum vs non-platinum-based chemotherapy. Multivariate cox proportional hazard model was used to calculate HR and 95% CIs adjusting for age, sex and pathologic stage. Results: The ORIEN cohort included 311 patients with resectable PDAC and available WES data. A total of 22 patients (7%) had an HRR pathway mutation. Of these, 8 (36%) received perioperative platinum-based chemotherapy and 9 (41%) a non-platinum based regimen, 4 patients (23%) received no perioperative systemic treatment. Frequency of HRR variants detected: BRCA2 n=8 (2.6%), BRCA1 n=3 (1%), ATM n=2 (0.6%), ARID1A n=1 (0.3%), BRIP1 n=1 (0.3%), CHECK2 n=1 (0.3%), FANCG n=1 (0.3%), PALPB2 n=1 (0.3%), RAD50 n=4 (1.3%), RAD51C n=1 (0.3%). The mOS for patients with HRR mutations exposed to perioperative platinum-based chemotherapy was 3.5 years (95% CI 3.4-NA), patients with HRR mutation but no platinum exposure had a mOS of 1.2 years (CI 0.9-NA). In patients with no HRR mutation exposed to platinum-based chemotherapy mOS was 2.7 years (CI 2.3-3.9) and in those without exposure mOS was 2.9 years, p=0.43. Comparison of risk of death between the 4 groups is demonstrated in the table. Conclusions: There was a trend towards improved survival in patients with PDAC who harbored a HRR pathway mutation and were treated with perioperative platinum-based chemotherapy compared to those with no platinum exposure. Our results highlight the importance of identifying patients with HRD beyond BRCA and the need for large prospective studies in the perioperative setting to further assess their predictive role. [Table: see text]

S1P/ceramides and cytokines as potential biomarkers of response following administration of bxq-350

e15007

Background: BXQ-350 was investigated in a Phase 1 dose-escalation safety study of all-comer cancer patients with advanced solid malignancies, including high grade gliomas ( NCT02859857 ) (safety/efficacy results reported in a separate abstract). The primary objective of this single agent study was to describe the safety profile and to determine the maximum tolerated dose. Multiple secondary parameters were included to characterize BXQ-350’s pharmacokinetic parameters, efficacy profile and elucidation of potential biomarkers. BXQ-350 is a nanovesicle of recombinantly expressed Saposin C (SapC) and dioleoylphosphatidylserine. In nature, SapC is a protein encoded by the Psap gene, and serves as an allosteric activator of several enzymes involved in sphingolipid/ceramide metabolism, enzymes which are being investigated as novel therapeutic targets in cancers. Indeed, sphingolipids are a class of bioactive signaling molecules implicated in multiple cellular processes and molecular pathways. Amongst these sphingolipids, Sphingosine-1-Phosphate (S1P) induces cancer cell survival and proliferation, activates multiple oncogenic pathways, and promotes a pro-tumoral microenvironment. SapC has broad anticancer activity, lowering S1P and increasing ceramides, also inducing an anti-tumoral immune response. Methods: Lipodomic analysis (sphingolipids) and cytokines were analyzed in plasma samples of a subset of patients enrolled in this study. Results: Analysis of plasma biomarker samples, collected throughout the period patients were on study, reveals notable changes of circulating sphingolipids and cytokines. A subset of patients exhibited clinical benefits following BXQ-350 administration (see other presentation for details; ̃17% of the evaluable patients remained on study up to Cycle 6; and 8 patients (̃11%) with PFS> 6 months). Concomitant circulating changes in S1P and other ceramides may be indicative of treatment effect. Also, concurrent changes in circulating levels of pro/antitumoral cytokines were noted. Conclusions: While these results are exploratory and preliminary in nature, these initial results warrant further investigation. These observations will be further explored in specific cancer and non-cancer indications. Clinical trial information: 02859857.

The impact of germline and somatic mutations in the homologous recombination repair pathway in pancreatic cancer patients who undergo perioperative chemotherapy

602

Background: Limited data is available regarding the effects of germline and somatic mutations in the homologous recombination repair (HRR) pathway in patients with resectable pancreatic cancer and exactly which mutations can be targeted with platinum-based chemotherapy. We aimed to assess the impact of HRR pathway mutations in a large cohort of pancreatic patients who underwent curative intent surgical resection. Methods: Patients with resectable pancreatic cancer who underwent perioperative chemotherapy, diagnosed from 1999-2020 from the participating members of the Oncology Research Information Exchange Network (ORIEN) were included in the study. Patients with germline and somatic whole exome sequencing data were analyzed for known pathogenic and likely pathogenic variants according to ClinVar in the following HRR pathway genes: BRCA1, BRCA2, PALB2, BRIP1, BRAD1, ATM, RAD51C, RAD51, RAD50, CHECK2, FANCC, FANCA, MRE11 and XRCC2. The Kaplan Meier method was used to compare median overall survival (OS) between patients with adenocarcinoma, with and without HRR pathway mutations. Multivariate cox proportional hazard model was used to calculate HR and 95% CI adjusting for age at diagnosis, sex and pathologic stage. Results: During the study period, the ORIEN cohort included 417 patients with resectable pancreatic cancer and whole exome sequencing. Of these 313 (75%) patients had adenocarcinoma and 104 (25%) neuroendocrine tumor. A total of 19 patients (5%) had an HRR pathway mutation - 15 (5%) in the adenocarcinoma group and 4 (4%) in the neuroendocrine group. In the adenocarcinoma group, 97 (31%) patients underwent platinum-based perioperative chemotherapy. Median OS was 2.8 years (IQR 2.5-3.3) in the adenocarcinoma group without HRR pathway mutation and 3.8 years (IQR 3.4-NA) in the group with HRR pathway mutation (HR 0.6: 95% CI 0.3-1.4, p = 0.76). Conclusions: There was a trend towards improved survival in patients with adenocarcinoma receiving perioperative platinum-based chemotherapy with HRR pathway mutations compared to those without a mutation. This finding supports previous data in the literature regarding the prognostic role of HRR pathway alterations in pancreatic cancer. Larger prospective studies are needed to assess the predictive role of these mutations in the perioperative setting in response to platinum-based chemotherapy.

Long-Term Follow-Up of Fractional CO2 Laser Therapy for Genitourinary Syndrome of Menopause in Breast Cancer Survivors

(1) Background: The objective of this study was to determine the long-term efficacy of fractional CO₂ laser therapy in breast cancer survivors. (2) Methods: This was a single-arm study of breast cancer survivors. Participants received three treatments of fractional CO₂ laser therapy and returned for a 4 week follow-up. Participants were contacted for follow-up at annual intervals. The Vaginal Assessment Scale (VAS), the Female Sexual Function Index (FSFI), the Female Sexual Distress Scare Revised (FSDS-R), the Urinary Distress Inventory (UDI), and adverse events were collected and reported for the two-year follow-up. The changes in scores were compared between the four-week and two-year and the one-year and two-year follow-ups using paired t-tests. (3) Results: In total, 67 BC survivors were enrolled, 59 completed treatments and the four week follow-up, 39 participated in the one-year follow-up, and 33 participated in the two-year follow-up. After initial improvement in the VAS from baseline to the four week follow-up, there was no statistically significant difference in the VAS score (mean Δ 0.23; 95% CI [−0.05, 0.51], p = 0.150) between the four week follow-up and the two-year follow-up. At the two-year follow-up, the FSFI and FSDS-R scores remained improved from baseline and there was no statistically significant change in the FSFI score (mean Δ −0.83; 95% CI [−3.07, 2.38] p = 0.794) or the FSDS-R score (mean Δ −2.85; 95% CI [−1.88, 7.59] p = 0.227) from the one to two-year follow-up. The UDI scores approached baseline at the two-year follow-up; however, the change between the one- and two-year follow-ups was not statistically significant (mean Δ 4.76; 95% CI [−1.89, 11.41], p = 0.15). (4) Conclusions: Breast cancer survivors treated with fractional CO₂ laser therapy have sustained improvement in sexual function two years after treatment completion, suggesting potential long-term benefit.

Multicenter randomized phase II trial of atezolizumab with or without cobimetinib in biliary tract cancers

BACKGROUNDMEK inhibitors have limited activity in biliary tract cancers (BTCs) as monotherapy but are hypothesized to enhance responses to programmed death ligand 1 (PD-L1) inhibition.METHODSThis open-label phase II study randomized patients with BTC to atezolizumab (anti-PD-L1) as monotherapy or in combination with cobimetinib (MEK inhibitor). Eligible patients had unresectable BTC with 1 to 2 lines of prior therapy in the metastatic setting, measurable disease, and Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 1. The primary endpoint was progression-free survival (PFS).RESULTSSeventy-seven patients were randomized and received study therapy. The trial met its primary endpoint, with a median PFS of 3.65 months in the combination arm versus 1.87 months in the monotherapy arm (HR 0.58, 90% CI 0.35-0.93, 1-tail P = 0.027). One patient in the combination arm (3.3%) and 1 patient in the monotherapy arm (2.8%) had a partial response. Combination therapy was associated with more rash, gastrointestinal events, CPK elevations, and thrombocytopenia. Exploratory analysis of tumor biopsies revealed enhanced expression of antigen processing and presentation genes and an increase in CD8/FoxP3 ratios with combination treatment. Patients with higher baseline or lower fold changes in expression of certain inhibitory ligands (LAG3, BTLA, VISTA) on circulating T cells had evidence of greater clinical benefit from the combination.CONCLUSIONThe combination of atezolizumab plus cobimetinib prolonged PFS as compared with atezolizumab monotherapy, but the low response rate in both arms highlights the immune-resistant nature of BTCs.TRIAL REGISTRATIONClinicalTrials.gov NCT03201458.FUNDINGNational Cancer Institute (NCI) Experimental Therapeutics Clinical Trials Network (ETCTN); F. Hoffmann-La Roche, Ltd.; NCI, NIH (R01 CA228414-01 and UM1CA186691); NCI's Specialized Program of Research Excellence (SPORE) in Gastrointestinal Cancers (P50 CA062924); NIH Center Core Grant (P30 CA006973); and the Passano Foundation.

In Vitro and In Vivo Inhibition of MATE1 by Tyrosine Kinase Inhibitors

The membrane transport of many cationic prescription drugs depends on facilitated transport by organic cation transporters of which several members, including OCT2 (SLC22A2), are sensitive to inhibition by select tyrosine kinase inhibitors (TKIs). We hypothesized that TKIs may differentially interact with the renal transporter MATE1 (SLC47A1) and influence the elimination and toxicity of the MATE1 substrate oxaliplatin. Interactions with FDA-approved TKIs were evaluated in transfected HEK293 cells, and in vivo pharmacokinetic studies were performed in wild-type, MATE1-deficient, and OCT2/MATE1-deficient mice. Of 57 TKIs evaluated, 37 potently inhibited MATE1 function by >80% through a non-competitive, reversible, substrate-independent mechanism. The urinary excretion of oxaliplatin was reduced by about 2-fold in mice with a deficiency of MATE1 or both OCT2 and MATE1 (p < 0.05), without impacting markers of acute renal injury. In addition, genetic or pharmacological inhibition of MATE1 did not significantly alter plasma levels of oxaliplatin, suggesting that MATE1 inhibitors are unlikely to influence the safety or drug-drug interaction liability of oxaliplatin-based chemotherapy.

Assessment of Leptomeningeal Carcinomatosis Diagnosis, Management and Outcomes in Patients with Solid Tumors Over a Decade of Experience

Objective

Leptomeningeal carcinomatosis (LMC), a common complication of advanced malignancies, is associated with high morbidity and mortality, yet diagnosis and treatment decisions remain challenging. This study describes the diagnostic and treatment modalities for LMC and identifies factors associated with overall survival (OS).

Materials and Methods

We performed a single-institution retrospective study (registration #: OSU2016C0053) of 153 patients diagnosed with LMC treated at The Ohio State University, Comprehensive Cancer Center, (OSUCCC)-James between January 1, 2010 and December 31, 2015.

Results

Median age at diagnosis was 55.7 years, and 61% had Eastern Cooperative Oncology Group baseline performance status ≤1. Most common primary tumors were breast (43%), lung (26%), and cutaneous melanoma (10%). At presentation, most patients were stage III-IV (71%) with higher grade tumors (grade III: 46%). Metastases to bone (36%), brain (33%), and lung (12%) were the most common sites with a median of 0.5 years (range, 0-14.9 years) between the diagnosis of first metastasis and of LMC. 153 (100%) patients had MRI evidence of LMC. Of the 67 (44%) who underwent lumbar puncture (LP), 33 (22%) had positive cerebrospinal fluid (CSF) cytology. Most patients received radiotherapy for LMC (60%) and chemotherapy (93%) for either the primary disease or LMC. 28 patients received intrathecal chemotherapy, 22 of whom had a primary diagnosis of breast cancer. 98% died with median OS of all patients was 1.9 months (95% CI: 1.3-2.5 months).

Conclusion

Despite improved treatments and targeted therapies, outcomes of LMC remain extremely poor. Positive CSF cytology was associated with lower OS in patients who had cytology assessed and specifically in patients with breast cancer. CSF cytology serves as an important indicator for prognosis and helps aid in developing individualized therapeutic strategies for patients with LMC.

Safety and efficacy of the anti-CD73 monoclonal antibody (mAb) oleclumab ± durvalumab in patients (pts) with advanced colorectal cancer (CRC), pancreatic ductal adenocarcinoma (PDAC), or EGFR-mutant non-small cell lung cancer (EGFRm NSCLC)

9047

Background: Upregulation of CD73 in multiple cancers increases adenosine production, leading to local immunosuppression. Oleclumab, a human IgG1λ mAb, inhibits CD73 function and may increase antitumor immunity. Initial data from a Phase I, first-in-human, dose-escalation and expansion study showed that oleclumab ± durvalumab had manageable safety and encouraging clinical activity in pts with advanced CRC or PDAC. We report updated safety and activity in these cohorts and the first results in an expansion cohort of pts with advanced EGFRm NSCLC. Methods: Previously treated pts with histologically or cytologically confirmed microsatellite stable CRC, PDAC, or EGFRm NSCLC received oleclumab 5–40 mg/kg (escalation) and 40 mg/kg (expansion) IV Q2W, alone (escalation only) or with durvalumab 10 mg/kg IV Q2W. The primary objective was safety; secondary efficacy objectives included objective response (OR) per RECIST v1.1 and duration of response (DoR). Results: 66 pts were enrolled in the escalation phase (35 CRC, 31 PDAC) and 126 in the expansion phase (42 CRC, 42 PDAC, 42 EGFRm NSCLC). At data cutoff (DCO; June 9, 2020), the median number of oleclumab doses was 4 in pts on monotherapy (range 1–26) and 4 in pts on combination therapy across both phases (range 1–76). In the escalation phase, there were no DLTs in pts on monotherapy or combination therapy; treatment-related adverse events (TRAEs) occurred in 54.8% of pts on monotherapy (Grade 3–4 in 7.1%) and 54.2% of pts on combination therapy (Grade 3–4 in 20.8%); fatigue was the most common TRAE with both regimens. No TRAEs resulted in death. In previous interim analyses before this DCO, no ORs were reported in the escalation phase. In the expansion phase, 5 pts were treated for ≥12 mos; 6 pts were ongoing at DCO. TRAEs occurred in 54.0% (Grade 3–5 in 15.1%); the most common TRAEs were fatigue (15.1%), diarrhea (9.5%), and rash (7.1%). One pt had a TRAE resulting in death (systemic inflammatory response syndrome). ORs were seen in 1 CRC pt (DoR 35.9+ mos [+ = ongoing response]), 2 PDAC pts (DoR 22.1+ and 28.6+ mos), and 4 EGFRm NSCLC pts (DoR range 5.6 to 15.7+ mos, median not reached; only 1 of the 4 pts had ≥25% programmed cell death ligand-1 [PD-L1]+ tumor cells). Nine CRC pts, 8 PDAC pts, and 9 EGFRm NSCLC pts had SD. Of 6 pts with matched biopsies who received combination therapy, 5 had increases in CD8+ T cells, PD-L1, and granzyme B. Baseline tumor CD73 expression and association with clinical response will be presented. Conclusions: Oleclumab ± durvalumab had a tolerable safety profile and combination therapy showed promising antitumor activity in EGFRm NSCLC. ORs and SD were durable, even in tumor types that are generally immunotherapy-resistant. Clinical trial information: NCT02503774.

Biologically optimized schedule of gemcitabine and nab-paclitaxel regimen in metastatic pancreatic adenocarcinoma

TPS4168

Background: Metastatic pancreatic adenocarcinoma has a poor prognosis, and improvements in therapy have been challenging. Alongside efforts in developing novel agents, there is a need to optimize and maximize the benefit of currently approved drugs. Gemcitabine + nab-paclitaxel is a frequently used regimen for pancreatic adenocarcinoma. Nab-paclitaxel is albumin–bound chemotherapy; hence the role of albumin uptake is critical for its effect. Caveolae are small membrane invaginations essential for transendothelial albumin uptake. Cav-1 is the principal structural component of caveolae. Williams and colleagues have published a series of preclinical studies demonstrating that tumor cell-specific Cav-1 expression directly correlates with albumin and albumin-bound chemotherapy uptake and subsequent apoptotic response in tumor cells. In vitro studies showed that exposure of pancreatic cancer cells to Gemcitabine resulted in up-regulation of Cav-1 peaking 48 hours after gemcitabine exposure. This Cav-1 up-regulation correlated with increased temporal albumin cellular uptake. In addition, Williams and colleagues noted that exposure of pancreatic cancer cell lines to Gemcitabine resulted in a time–specific re-entry of cells into the G2/M phase (nab-paclitaxel cytotoxicity phase) between 48-60 hours after gemcitabine treatment. Collectively this data suggest that infusing nab-paclitaxel after 48 hours of gemcitabine infusion would be optimal for both increased uptake as well as increased susceptible tumor cells. We had previously shown this effect on multiple cell lines as well as mouse models. Methods: This is a phase II trial; patients will receive a standard of care chemotherapy regimen consisting of FDA-approved Gemcitabine + nab-paclitaxel with modification of the schedule to deliver nab-paclitaxel 48 hours (2 days) after gemcitabine infusions. The primary endpoint is ORR, with a null hypothesis of 20% vs. a target of 35%. Employing a 2-stage design (minimax) and assuming 80% power and a 0.05 significance level, a total of 53 patients will be required. In the first stage, if at least 7/31 patients respond to therapy, an additional 22 patients will be added for a total of 53 patients. The study will be terminated early if ≤ six patients respond in the first stage. Observation of response in at least 16/53 patients would be required to warrant further investigation of this infusion schedule of combination therapy. The secondary endpoints include the safety of the regimen schedule, Relative dose intensity, disease control rate, PFS, and OS. The trial opened to enrollment in June 2020 and is accepting patients. Clinical trial information: NCT04115163.

Patient-reported sexual function of breast cancer survivors with genitourinary syndrome of menopause after fractional CO2 laser therapy

OBJECTIVE

The objective of this pilot study was to evaluate the change in sexual function following treatment with fractional CO2 laser therapy in breast cancer (BC) survivors with genitourinary syndrome of menopause (GSM).

METHODS

A single-arm feasibility study of BC survivors with symptoms of GSM, including dyspareunia and/or vaginal dryness, was conducted. Participants who received three treatments with fractional CO2 laser and 4-week follow-up were contacted for patient-reported outcomes and adverse events at 12 months. Sexual function was measured using the Female Sexual Function Index (FSFI) and Female Sexual Distress Scale Revised (FSDS-R). Descriptive statistics were calculated for patient demographics and disease characteristics for the set of participants who agreed to long-term follow-up and those who were lost to follow-up. FSFI and FSDS-R scores were summarized at baseline, 4 weeks and 12 months, as well as the change from baseline, and were compared using a Wilcoxon signed rank test.

RESULTS

A total of 67 BC survivors enrolled, 59 completed treatments and 4-week follow-up; 39 participated in the 12 month follow-up. The overall FSFI score improved from baseline to 4-week follow-up (median Δ 8.8 [Q1, Q3] (QS) (2.2, 16.7)], P < 0.001). There were improvements at 4 weeks in all domains of the FSFI (P < 0.001 for each) including desire (median Δ 1.2; QS [0.6, 1.8]), arousal (median Δ 1.2; QS [0.3, 2.7]), lubrication (median Δ 1.8 (0, 3.3), orgasm (median Δ 1.2; QS [0, 3.6]), satisfaction (median Δ 1.6 (0.4, 3.2)), and pain (median Δ 1.6 (0, 3.6). The FSDS-R score also improved from baseline to 4-week follow-up (median Δ -10.0; QS [-16, -5] P < 0.001) indicating less sexually related distress. The scores of the FSFI and FSDS-R remained improved at 12 months and there were no serious adverse events reported.

CONCLUSIONS

In BC survivors with GSM, the total and individual domain scores of the FSFI and the FSDS-R improved after fractional CO2 laser therapy.

Phase II/III study of SM-88 in patients with metastatic pancreatic cancer

437

Background: SM-88 (racemetyrosine, Tyme Inc) is a dysfunctional tyrosine derivative used with MPS (methoxsalen 10mg, phenytoin 50mg and sirolimus 0.5mg). SM-88 was well tolerated with improvement in survival among select heavily pretreated PDAC patients who achieved stable disease (HR 0.08, p = 0.02) (Noel et al. Annal Oncol 2019). Circulating tumor cells (CTCs) were prognostic in identifying a PDAC subgroup that may be more likely to benefit from SM-88. Preliminary radiomic analysis of the largest metastases at baseline correlated with baseline CTCs (Ocean et al, Annal Oncol 2019). Here we describe the subsequent randomized portion of the trial in third-line patients only, of SM-88 vs physician/patient choice chemotherapy, to evaluate the potential role of SM-88 in metastatic PDAC through analysis of CTCs and passively acquired biometrics data from a wearable device. Methods:Prospective open-label RCT (Tyme 88 Panc Part 2, NCT03512756) after 2 prior lines for metastatic PDAC. A cell adhesion matrix (CAM) was used to enrich solitary CTCs and cells in clusters floating in the medium after 24 hour culture. Isolated CTCs were collected each cycle on day 1, isolated, and enumerated by flow cytometry using the epithelial cell surface marker Epi+ and cellular uptake of green fluorescent labeled CAM (GCAM+). Results:As of Sept 15, 67 subjects were consented. Randomized and evaluable subjects (n=38) included: mean age 65y (45-86); BMI 24.6 (18.8-38.7); female 39.5%; White 76.3%. Of treated subjects 65.8% (25/38) had 166 AEs, with 25.7% (26/101) being at least possibly SM-88-related, with 1 Grade 3. Four CTC subpopulations defined by GCAM, Epi+ and cluster status, were enumerated and correlated to each other (r=0.03-0.71). At least one CTC subpopulation was detected at baseline (mean 33.8 cells/2mL) in all subjects (n=27). The longest metastatic lesion diameter at baseline correlated with baseline CTCs (r=0.55 for Epi+ cluster; r=0.52 for GCAM+ cluster). CTCs were successfully separated and enumerated at each cycle for correlation with survival, response and other parameters. The median baseline daily step count during the first two weeks on treatment was 3993.8 (IQR: 2745.6 - 5078) for those alive vs. 689.3 (IQR: 630.0-2083.6) among deaths in evaluable subjects (p = NS). Passively acquired mean heart rate during week 3 on trial was 89.3 (SD 10.5) among those who died vs. 78.0 (SD 9.2) among those living; medians are 87.0 for deaths vs. 79.2 for alive (p= NS). Conclusions: In a preliminary exploratory analysis, passively acquired biometrics from a wearable device can be collected for correlation with other clinical outcomes. CTC collection and enumeration is also feasible for correlation with traditional trial outcomes. Given that the longest lesion diameter is correlated with CTCs at baseline, additional radiologic feature analysis (eg radiomics) may be important predictor of CTCs. SM-88 was well tolerated with no treatment-related Grade 4 or 5 events. Clinical trial information: NCT03512756.

Perspectives of Survivorship Care Plans Among Older Breast Cancer Survivors: A Pilot Study

The Commission on Cancer’s standard 3.3 represents a paradigm shift in the care of cancer survivors, recommending that survivors receive a treatment summary and survivorship care plan (SCPs). A focus on older breast cancer survivors is needed, as they are the majority of the breast cancer population and their experiences and perspectives of SCPs is limited in the literature. This pilot study utilized a mixed methods approach (focus groups and self-report questionnaire data) to gather information on older (≥65 years) breast cancer survivors’ perspectives of their SCPs, cancer survivorship, and communication with their health-care providers. The questionnaire was completed individually by the participants prior to the focus group and contained items on basic demographics and their health status following cancer treatment. The focus groups indicated that only a minority of women actually developed a SCP. Those who developed a SCP in collaboration with their providers valued the personal care and attention received. However, some participants reported poor communication with their providers and within their health-care team, resulting in frustration and confusion. Participants’ suggestions for ideal SCPs included better education and personalization, particularly in appropriate nutrition and exercise, and managing side effects and comorbidities. Lastly, the women believed that additional long-term care resources, such as health coaches, were important in improving their survivorship. These findings provide insight into enhancing the content, communication, and application of SCPs to improve the survivorship experience of older breast cancer survivors.

Implementing a multidisciplinary approach for older adults with Cancer: geriatric oncology in practice

BACKGROUND

Evidence-based practice in geriatric oncology is growing, and national initiatives have focused on expanding cancer care and research to improve health outcomes for older adults. However, there are still gaps between knowledge and practice for older adults with cancer.

MAIN TEXT

Here we provide a detailed methodology of geriatric oncology care delivery within a single institution. The Cancer and Aging Resiliency (CARE) clinic is a multidisciplinary approach for implementing geriatric-driven health care for older adults with cancer. The CARE clinic was developed as a direct response to recommendations targeting key multifactorial geriatric health conditions (e.g. falls, nutritional deficits, sensory loss, cognitive impairment, frailty, multiple chronic conditions, and functional status). The multidisciplinary team assesses and delivers a comprehensive set of recommendations, all in one clinic visit, to minimize burden on the patient and the caregiver. The CARE clinic consultative model is a novel approach integrating cancer subspecialties with geriatric oncology healthcare delivery.

CONCLUSIONS

Older adults with cancer have unique needs that are independent of routine oncology care. The CARE clinic model provides specific assessments and interventions to improve health outcomes among older adults with cancer.

CD200 promotes immunosuppression in the pancreatic tumor microenvironment

BACKGROUND

A significant challenge to overcome in pancreatic ductal adenocarcinoma (PDAC) is the profound systemic immunosuppression that renders this disease non-responsive to immunotherapy. Our supporting data provide evidence that CD200, a regulator of myeloid cell activity, is expressed in the PDAC microenvironment. Additionally, myeloid-derived suppressor cells (MDSC) isolated from patients with PDAC express elevated levels of the CD200 receptor (CD200R). Thus, we hypothesize that CD200 expression in the PDAC microenvironment limits responses to immunotherapy by promoting expansion and activity of MDSC.

METHODS

Immunofluorescent staining was used to determine expression of CD200 in murine and human PDAC tissue. Flow cytometry was utilized to test for CD200R expression by immune populations in patient blood samples. In vivo antibody blocking of CD200 was conducted in subcutaneous MT-5 tumor-bearing mice and in a genetically engineered PDAC model (KPC-Brca2 mice). Peripheral blood mononuclear cells (PBMC) from patients with PDAC were analyzed by single-cell RNA sequencing. MDSC expansion assays were completed using healthy donor PBMC stimulated with IL-6/GM-CSF in the presence of recombinant CD200 protein.

RESULTS

We found expression of CD200 by human pancreatic cell lines (BxPC3, MiaPaca2, and PANC-1) as well as on primary epithelial pancreatic tumor cells and smooth muscle actin+ stromal cells. CD200R expression was found to be elevated on CD11b+CD33+HLA-DRlo/- MDSC immune populations from patients with PDAC (p=0.0106). Higher expression levels of CD200R were observed in CD15+ MDSC compared with CD14+ MDSC (p<0.001). In vivo studies demonstrated that CD200 antibody blockade limited tumor progression in MT-5 subcutaneous tumor-bearing and in KPC-Brca2 mice (p<0.05). The percentage of intratumoral MDSC was significantly reduced in anti-CD200 treated mice compared with controls. Additionally, in vivo blockade of CD200 can also significantly enhance the efficacy of PD-1 checkpoint antibodies compared with single antibody therapies (p<0.05). Single-cell RNA sequencing of PBMC from patients revealed that CD200R+ MDSC expressed genes involved in cytokine signaling and MDSC expansion. Further, in vitro cytokine-driven expansion and the suppressive activity of human MDSC was enhanced when cocultured with recombinant CD200 protein.

CONCLUSIONS

These results indicate that CD200 expression in the PDAC microenvironment may regulate MDSC expansion and that targeting CD200 may enhance activity of checkpoint immunotherapy.

Trial in progress: A phase II open-label, randomized study of PARP inhibition (olaparib) either alone or in combination with anti-PD-L1 therapy (atezolizumab) in homologous DNA repair (HDR) deficient, locally advanced or metastatic non-HER2-positive breast cancer

TPS1102

Background: While immunostimulatory therapies have shown great success, a major challenge remains identification of mechanisms to effectively treat the majority of patients with so-called "non-inflamed" tumors lacking marked lymphocyte infiltration and PD-L1 expression. The DNA repair proficiency of a tumor may impact its potential for immune recognition and sensitivity to immune checkpoint blockade. Preclinically, PARP inhibition in HDR-deficient tumors has been shown to trigger antitumor immunity through a STING-dependent antitumor immune response. Effects of PARP inhibitors were augmented when combined with PD-1 blockade. We hypothesize that enhanced DNA damage and cell death induced by PARP inhibition in tumors with homology directed repair (HDR) deficiency will enhance adaptive anti-tumor immune responses and increase sensitivity to PD-1 axis blockers. Methods: This is a randomized, open-label phase II clinical trial exploring the PARP inhibitor olaparib either alone or in combination with the anti-PD-L1 human monoclonal antibody atezolizumab in BRCA1/2 mutated locally advanced or metastatic non-HER2-positive breast cancer. HDR deficiency is defined as the presence of deleterious BRCA 1/2 mutations. Randomization occurs in a 1:1 fashion to two arms: (1) olaparib 300 mg PO bid continuously in 21-day cycles or (2) olaparib 300 mg PO bid continuously in combination with atezolizumab 1200 IV every 3 weeks in 21-day cycles. Patients undergo baseline evaluations and pre-treatment biopsy within 2 weeks of starting therapy. Repeat biopsies are required at the time of first tumor assessment scan (6 weeks from the start of treatment) and in the event of disease progression. Correlative studies, including detailed analysis of the genomic profile and tumor immune contexture, will be performed at each biopsy time point. The primary objective is to compare progression free survival between the study arms. If progression occurs on the olaparib monotherapy arm, cross-over to the combination arm is allowed. This study began enrolling in August 2018; 47 of the planned 72 patients have been registered. Clinical trial information: NCT02849496 .

A phase Ib adaptive study of dasatinib for the prevention of oxaliplatin-induced neuropathy in patients with metastatic colorectal cancer receiving FOLFOX chemotherapy and bevacizumab

TPS12125

Background: Neurotoxicity is one of the most significant and disabling side effects of oxaliplatin and frequently limits the cumulative amount that can be used. The mechanism of oxaliplatin-induced neurotoxicity remains uncertain, although our preliminary studies suggest that oxaliplatin uptake by organic cation transporter 2 (OCT2) into mouse and rat dorsal root ganglion is a prerequisite for oxaliplatin-induced peripheral neuropathy. The activity of OCT2 is dependent on tyrosine phosphorylation by the SRC-kinase family member Yes1, which is highly sensitive to inhibition by several FDA-approved, small molecule kinase inhibitors such as dasatinib. We have previously shown that pre-treatment with oral dasatinib prevented acute and chronic oxaliplatin-induced peripheral neuropathy in mouse and rat models. Methods: This is a phase Ib dose-finding study of dasatinib given in combination with mFOLFOX6 with or without bevacizumab. The study explores the hypothesis that the addition of dasatinib prior to oxaliplatin will inhibit OCT2 activity and reduce oxaliplatin-induced neuropathy. This hypothesis will be tested in a Bayesian Phase 1b trial with adaptive dose selection using efficacy-toxicity trade-offs (modified toxicity-efficacy probability interval dose-finding design) in patients with confirmed stage IV colorectal cancer who are candidates for mFOLFOX6 with bevacizumab therapy. Patients who have documented peripheral neuropathy or prior exposure to oxaliplatin will be excluded. The primary objective is to determine the recommended Phase 2 dose which is defined as the lowest intermittent dose of dasatinib that affects serum biomarkers of OCT2, including methylnicotinamide and creatinine, by ≥2-fold without influencing the clearance of oxaliplatin by > 20%. The following doses will be used: oxaliplatin 85mg/m2 IV, 5FU bolus 400mg/m2 IV bolus with Leucovorin 400mg/m2, bevacizumab 5mg/kg, followed by infusional 5FU 2400mg/m2 IV over 46 hours given on a day 1 and 15 schedule every 28 days. Dasatinib will be administered at one of 2 dose levels – 100mg or 140mg po. Dasatinib will be given 24 hours and 30 mins prior to oxaliplatin on C1D14, C1D15 respectively and repeated on C1D28 and C2D1. Secondary objectives include evaluation of the influence of dasatinib on the pharmacokinetics of oxaliplatin and vice versa. Quality of life will be explored using the CIPN20 questionnaire. The trial opened to enrollment in Dec 2019 (NCT04164069) and is accepting patients. Clinical trial information: NCT04164069 .

A pilot study of Bruton’s tyrosine kinase inhibitor ibrutinib alone and in combination with PD-1 inhibitor nivolumab in patients with metastatic solid tumors

3111

Background: Myeloid-derived suppressor cells (MDSC) are expanded in cancer and promote immune suppression. We have shown that ibrutinib inhibits migration and immunosuppressive function of MDSC. Moreover, the combination of ibrutinib and a PD-L1 inhibitor has been found to have synergistic anti-tumor effects in a multiple solid tumor mouse models. Therefore, we conducted a pilot study testing the combination of ibrutinib and nivolumab in patients with metastatic solid tumors. Methods: Sixteen patients with advanced solid tumors were recruited to this trial. Ibrutinib was dosed as an oral single agent, starting 7 days prior to cycle 1 of nivolumab and given until cycle 1, day 8 of nivolumab. Nivolumab was administered intravenously on days 1 and 15 on 28-day cycles. Patients had blood samples collected prior to initiation of ibrutinib, day 1 of cycle 1, day 8 of cycle 1, day 1 of cycle 2, and at the time of disease progression. From these specimens, we measured circulating MDSC levels, other circulating immune subsets, T cell proliferation, and cytokines/chemokines levels. Circulating MDSC levels were measured by mass spectrometry. T cell function was evaluated by CFSE to monitor proliferating cells by dye dilution and cytokine/chemokine levels were measured with a U-PLEX assay. Data were analyzed using two-tailed, paired Student's t-tests to assess statistical significance. Results: An increase in circulating MDSC (22% to 28%; SD 9.158) levels was observed following 7 days of single-agent ibrutinib compared to baseline. However, in combination therapy, MDSC levels decreased (19%; SD 13.17) prior to cycle 2. Despite increasing levels of circulating MDSC, T cell function improved throughout the study. Furthermore, plasma levels of chemokines associated with MDSC recruitment and migration significantly decreased with ibrutinib treatment (IL-12, CCL2, CCL3, and CCL4). Of the 16 patients, four achieved a partial response and four achieved stable disease. Median progression free survival was 3.5 months and median overall survival was 11.5 months. Conclusions: The combination of ibrutinib and nivolumab was well tolerated, demonstrated early signs of immune modulation, and showed preliminary signs of promising clinical activity in patients with metastatic solid tumors. Clinical trial information: NCT03525925 .

Metastatic breast cancer patient perceptions of somatic tumor genomic testing

BACKGROUND

To assess metastatic breast cancer (MBC) patient psychological factors, perceptions, and comprehension of tumor genomic testing.

METHODS

In a prospective, single institution, single-arm trial, patients with MBC underwent next-generation sequencing at study entry with sequencing results released at progression. Patients who completed surveys before undergoing sequencing were included in the present secondary analysis (n = 58). We administered four validated psychosocial measures: Center for Epidemiologic Studies Depression Scale, Beck Anxiety Inventory, Trust in Physician Scale, and Communication and Attitudinal Self-Efficacy scale for Cancer. Genetic comprehension was assessed using 7-question objective and 6-question subjective measures. Longitudinal data were assessed (n = 40) using paired Wilcoxon signed rank and McNemar's test of agreement.

RESULTS

There were no significant differences between the beginning and end of study in depression, anxiety, physician trust, or self-efficacy (median time on study: 7.6 months). Depression and anxiety were positively associated with each other and both negatively associated with self-efficacy. Self-efficacy decreased from pre- to post-genomic testing (p = 0.05). Objective genetics comprehension did not significantly change from pre- to post-genomic testing, but patients expressed increased confidence in their ability to teach others about genetics (p = 0.04). Objective comprehension was significantly lower in non-white patients (p = 0.02) and patients with lower income (p = 0.04).

CONCLUSIONS

This is the only study, to our knowledge, to longitudinally evaluate multiple psychological metrics in MBC as patients undergo tumor genomic testing. Overall, psychological dimensions remained stable over the duration of tumor genomic testing. Among patients with MBC, depression and anxiety metrics were negatively correlated with patient self-efficacy. Patients undergoing somatic genomic testing had limited genomic knowledge, which varied by demographic groups and may warrant additional educational intervention.

CLINICAL TRIAL INFORMATION

NCT01987726, registered November 13, 2013.

Primary care physician's confidence and coordination regarding the survivorship care for older breast cancer survivors

PURPOSE

To examine primary care physician's (PCPs) internal (confidence, training) and external (communication, receipt of survivorship care plans (SCPs)) regarding their provision of survivorship care to older breast cancer survivors METHOD: A web-based questionnaire was completed individually by PCPs about their training and areas of survivorship they address under their care. A subset of survey participants was interviewed about survivorship care for older breast cancer survivors, care coordination, and areas of improvement regarding SCPs.

RESULTS

PCPs (n = 29) had an average 13.5 years in family practice. Forty-five percent surveyed as "somewhat confident" or "not confident" evaluating and managing the late effects of cancer treatment, and 25% surveyed as "somewhat confident" or "not confident" addressing the chronic comorbidities of older breast cancer survivors. More than half of PCPs surveyed that they reach out to their patients' oncologist "a little" or "none of the time" and that they receive SCPs "a little" or "none of the time." Semi-structured interviews also indicated that many PCPs did not receive a SCP from their patients' oncologists and that communication between the two providers regarding survivorship care was poor.

CONCLUSION

Participants indicated that PCP confidence in providing survivorship care is lacking and that lack of training, infrequent communication with oncologists, and underutilization of SCPs may contribute to this lack of confidence. These findings provide insight into the possible need for a well-defined shared care model, which has been encouraged but not always a routine part of survivorship care in various practice settings.

CEACAM6 as a candidate biomarker for pelareorep sensitivity in pancreatic adenocarcinoma (PDAC)

746

Background: Pelareorep is a proprietary formulation of live, replication-competent, naturally occurring Reovirus Type 3 Dearing strain. A randomized phase II trial of pelareorep in combination with carboplatin and paclitaxel in first-line treatment of metastatic PDAC (NCT01280058) was performed. Although pelareorep did not improve the primary endpoint of progression-free survival compared to carboplatin and paclitaxel alone, impressive durable responses were seen in the pelareorep arm in some patients (pts). Further, prior studies have noted the immunomodulatory carcinoembryonic antigen-related cell adhesion molecule (CEACAM6/CD66c) as a receptor for specific viral subtypes. We thus speculated that altered CEACAM6 levels may be predictive for pelareorep sensitivity. Methods: Pre-treatment tissue biopsies were collected prior enrolment for all 73 pts on study. Evaluable pts with transcriptomic data was available for only 31 pts. RNA was purified from FFPE tissue and gene expression analysis was performed using SensationPlus FFPE Amplification and WT labelling kit and the Human Transcriptome Array 2.0. CEACAM6 protein expression was determined by immunohistochemistry. Differential gene expression and survival analysis using were performed in R/Bioconductor. Appropriate corrections for multiplicity were performed. Results: When comparing extraordinary responders in the pelareorep treated arm to those with poor outcomes, low levels of CEACAM6 mRNA expression were associated with prolonged PFS in pelareorep-treated pts (adjusted p = 0.05). This effect was not seen in non-pelareorep treated pts. The luminal, but not the cytoplasmic immunohistochemistry score, was highly correlated with mRNA expression levels of CEACAM6, p = 0.001. Modulation of CEACAM6 in vitro and in vivo are underway. Conclusions: CEACAM6 may be a candidate biomarker of sensitivity to pelareorep and, in theory, could improve viral trafficking of this compound in tumor cells. Clinical trial information: NCT01280058 . [Table: see text]

Prospective Decision Analysis Study of Clinical Genomic Testing in Metastatic Breast Cancer: Impact on Outcomes and Patient Perceptions

PURPOSE

To evaluate the impact of targeted DNA sequencing on selection of cancer therapy for patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

In this prospective, single-center, single-arm trial, patients with MBC were enrolled within 10 weeks of starting a new therapy. At enrollment, tumor samples underwent next-generation sequencing for any of 315 cancer-related genes to high depth (> 500×) using FoundationOne CDx. Sequencing results were released to providers at the time of disease progression, and physician treatment recommendations were assessed via questionnaire. We evaluated three prespecified questions to assess patients' perceptions of genomic testing.

RESULTS

In all, 100 patients underwent genomic testing, with a median of five mutations (range, 0 to 13 mutations) detected per patient. Genomic testing revealed one or more potential therapies in 98% of patients (98 of 100), and 60% of patients (60 of 100) had one or more recommended treatments with level I/II evidence for actionability. Among the 94 genomic text reports that were released, there was physician questionnaire data for 87 patients (response rate, 92.6%) and 31.0% of patients (27 of 87) had treatment change recommended by their physician. Of these, 37.0% (10 of 27) received the treatment supported by genomic testing. We did not detect a statistically significant difference in time-to-treatment failure (log-rank P = .87) or overall survival (P = .71) among patients who had treatment change supported by genomic testing versus those who had no treatment change. For patients who completed surveys before and after genomic testing, there was a significant decrease in confidence of treatment success, specifically among patients who did not have treatment change supported by genomic testing (McNemar's test of agreement P = .001).

CONCLUSION

In this prospective study, genomic profiling of tumors in patients with MBC frequently identified potential treatments and resulted in treatment change in a minority of patients. Patients whose therapy was not changed on the basis of genomic testing seemed to have a decrease in confidence of treatment success.

Ibrutinib Potentiates Antihepatocarcinogenic Efficacy of Sorafenib by Targeting EGFR in Tumor Cells and BTK in Immune Cells in the Stroma

Hepatocellular carcinoma (HCC), the most prevalent primary liver cancer, is a leading cause of cancer-related death worldwide because of rising incidence and limited therapy. Although treatment with sorafenib or lenvatinib is the standard of care in patients with advanced-stage HCC, the survival benefit from sorafenib is limited due to low response rate and drug resistance. Ibrutinib, an irreversible tyrosine kinase inhibitor (TKI) of the TEC (e.g., BTK) and ErbB (e.g., EGFR) families, is an approved treatment for B-cell malignancies. Here, we demonstrate that ibrutinib inhibits proliferation, spheroid formation, and clonogenic survival of HCC cells, including sorafenib-resistant cells. Mechanistically, ibrutinib inactivated EGFR and its downstream Akt and ERK signaling in HCC cells, and downregulated a set of critical genes involved in cell proliferation, migration, survival, and stemness, and upregulated genes promoting differentiation. Moreover, ibrutinib showed synergy with sorafenib or regorafenib, a sorafenib congener, by inducing apoptosis of HCC cells. In vivo, this TKI combination significantly inhibited HCC growth and prolonged survival of immune-deficient mice bearing human HCCLM3 xenograft tumors and immune-competent mice bearing orthotopic mouse Hepa tumors at a dose that did not exhibit systemic toxicity. In immune-competent mice, the ibrutinib-sorafenib combination reduced the numbers of BTK⁺ immune cells in the tumor microenvironment. Importantly, we found that the BTK⁺ immune cells were also enriched in the tumor microenvironment in a subset of primary human HCCs. Collectively, our findings implicate BTK signaling in hepatocarcinogenesis and support clinical trials of the sorafenib-ibrutinib combination for this deadly disease.

Comparison of conventional versus liposomal irinotecan in combination with fluorouracil for advanced pancreatic cancer: a single-institution experience

The majority of pancreatic cancers are diagnosed at an advanced stage, when surgical options are limited and treatment relies on systemic chemotherapy. In the NAPOLI-1 trial, liposomal irinotecan in combination with fluorouracil (nal-iri/5FU) was shown to improve overall survival when compared to fluorouracil alone for metastatic pancreatic cancer. Other retrospective studies have shown the combination of fluorouracil and conventional irinotecan (FOLFIRI) to be a viable option, though no randomized trials have compared nal-iri/5FU to FOLFIRI. The purpose of this single-center, retrospective, cohort study was to determine if nal-iri/5FU and FOLFIRI are similarly effective for the treatment of advanced pancreatic cancer. Due to the potential for treatment bias, inverse probability of treatment weighting was utilized to correct for baseline differences between the groups. The primary outcome of progression-free survival was similar at 4.1 months for nal-iri/5FU and 3.1 months for FOLFIRI. Overall survival and adverse effect frequency were also similar. Pegfilgrastim was used in 16% and 15% of patients, respectively, and nal-iri/5FU patients required significantly less atropine during treatment (36 vs. 70%). A cost analysis was conducted and concluded that the treatment with nal-iri/5FU was nearly 30 times more expensive than FOLFIRI treatment. Together, these data suggest a potential role for FOLFIRI for the treatment of advanced pancreatic cancer in the absence of clear benefits in effectiveness, toxicity, or cost for nal-iri/5FU.

Association of Liver-Directed Local Therapy With Overall Survival in Adults With Metastatic Intrahepatic Cholangiocarcinoma

IMPORTANCE

Intrahepatic cholangiocarcinoma is an aggressive hepatobiliary malignant neoplasm characterized by local progression and frequent metastasis. Definitive local therapy to the liver in the setting of metastatic intrahepatic cholangiocarcinoma may improve overall survival.

OBJECTIVE

To compare the overall survival of patients with metastatic intrahepatic cholangiocarcinoma treated with chemotherapy alone vs chemotherapy with definitive liver-directed local therapy.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used the National Cancer Database to identify 2201 patients with metastatic intrahepatic cholangiocarcinoma diagnosed between January 2004 and December 2014 who received chemotherapy with or without hepatic surgery or external beam radiation to a dose 45 Gy or higher. Multiple imputation, Cox proportional hazards, propensity score matching, and landmark analysis were used to adjust for confounding variables. Analyses were performed between September 2018 and February 2019.

EXPOSURES

Chemotherapy alone and chemotherapy with liver-directed surgery or radiation.

MAIN OUTCOMES AND MEASURES

Overall survival.

RESULTS

A total of 2201 patients (1131 [51.4%] male; median [interquartile range] age, 63 [55-71] years) who received chemotherapy alone (2097 [95.3%]) or chemotherapy with liver-directed local therapy (total, 104 [4.7%]; surgery, 76 [73.1%]; radiation, 28 [26.9%]) were identified. Patients treated with chemotherapy alone had larger median (interquartile range) primary tumor size (7.0 [4.4-10.0] cm vs 5.6 [4.0-8.3] cm; P = .048) and higher frequency of lung metastases (383 [25.9%] vs 7 [6.7%]; P = .004). Patients treated with liver-directed local therapy had higher frequency of distant lymph node metastases (34 [32.7%] vs 528 [25.2%]; P = .045). Liver-directed local therapy was associated with higher overall survival compared with chemotherapy alone on multivariable analysis (hazard ratio [HR], 0.60; 95% CI, 0.48-0.74; P < .001). A total of 208 patients treated with chemotherapy alone were propensity score matched with 104 patients treated with chemotherapy plus liver-directed local therapy. Liver-directed local therapy continued to be associated with higher overall survival (HR, 0.57; 95% CI, 0.44-0.74; P < .001), which persisted on landmark analysis at 3 months (HR, 0.61; 95% CI, 0.47-0.79; log-rank P < .001), 6 months (HR, 0.68; 95% CI, 0.50-0.92; log-rank P = .01), and 12 months (HR, 0.68; 95% CI, 0.47-0.98; log-rank P = .04).

CONCLUSIONS AND RELEVANCE

In this study, the addition of hepatic surgery or irradiation to chemotherapy was associated with higher overall survival when compared with chemotherapy alone in patients with metastatic intrahepatic cholangiocarcinoma. These findings may be valuable given the paucity of available data for this disease and should be validated in an independent cohort or prospective study.

Assessment of Leptomeningeal Carcinomatosis Diagnosis and Outcomes from 2005 to 2015 at Ohio State University

e13554

Background: Leptomeningeal carcinomatosis (LMC) is a complication of advanced malignancies wherein primary tumors metastasize to the leptomeninges surrounding brain and spinal cord. LMC complicates 4-15% of malignant solid tumors with incidence increasing as survival of patients with advanced cancer improves. Diagnostic methods include magnetic resonance imaging (MRI) and cerebrospinal fluid (CSF) cytology. MRI findings may be nonspecific, and the gold standard of diagnosis is malignant cytology on CSF analysis. We assessed detection methods, incidence, and outcomes of LMC at The Ohio State University Comprehensive Cancer Center from 2005-2015. Methods: This was an IRB-approved single-institution retrospective study of 160 patients with confirmed diagnosis of LMC who were treated at the OSUCCC-James between Jan 1, 2005 and Dec 31, 2015. Patients with hematologic and central nervous system malignancies were excluded. Descriptive statistics were used to summarize demographic and clinical characteristics. Overall survival (OS) was defined as time from LMC diagnosis to death or last known follow-up, and was generated using Kaplan-Meier methods. Results: Median age of LMC diagnosis was 55.8 years (range: 48, 62.5). 69 (43%) patients had primary breast cancer, 41 (26%) had lung cancer, and 17 (11%) had melanoma. 73 patients (46%) presented with stage IV disease at initial diagnosis of the primary cancer, 41 (26%) with stage III disease, and 26 (16%) with stage II disease. Median time from diagnosis of primary cancer to diagnosis of LMC was 2 years (range: 0, 31.2). 158 (99%) patients had metastases at the time of LMC diagnosis, predominantly in bone (36%) or brain (36%). Median OS was 1.9 months (CI: 1.3, 2.5). 160 (100%) patients had an MRI of the brain or spine and 155 (97%) had MRI findings consistent with LMC. 75 (47%) patients underwent lumbar puncture, and 39 (52%) had CSF cytology positive for malignancy. Conclusions: Patients with LMC commonly presented with stage IV breast cancer, lung cancer, or melanoma with metastases to the brain or bone. Despite treatment, prognosis remains poor and confirmation of diagnosis can be challenging. Clinicians should have a low threshold for investigating LMC in high risk patients presenting with neurologic signs or symptoms.

Neoadjuvant FOLFIRINOX versus adjuvant gemcitabine in pancreatic cancer

4123

Background: In the metastatic or adjuvant setting for pancreatic cancer, the combination chemotherapy of fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX) resulted in longer overall survival (OS) compared to gemcitabine therapy. We conducted an institutional study to compare the efficacy of neoadjuvant modified FOLFIRINOX (neo-mFOLFIRINOX) to adjuvant gemcitabine (adj-gem) for pancreatic cancer patients who completed resection. Methods: The study retrospectively enrolled patients from 2006 to 2017 from Ohio State University. While patients who received adjuvant gemcitabine were considered to be resectable upfront, patients who received neo-mFOLFIRINOX were either staged as borderline resectable (BR) or un-resectable (UR) by the institutional tumor board group. 111 patients received adj-gem (average cycles, 5.5) and 52 patients received neo-mFOLFIRINOX (average cycles, 3.5). The survival rates were determined by the Kaplan-Meier method and analyzed using Cox regression and log-rank test. Results: At a median follow up of 21.3 months, the median OS was 35.4 months in the neo-mFOLFIRINOX group and 21.8 months in the adj-gem group (hazard ratio, 0.56, 95% confidence interval (CI), 0.37-0.84 p = 0.005). The OS rate at 3 years was 46% in the neo-mFOLFIRINOX group and 22% in the adjuvant gemcitabine group (p = 0.001). The median disease free survival (DFS) was 18.6 months in the neo-mFOLFIRINOX group and 12.0 months in the adj-gem group (hazard ratio, 0.63, 95% CI, 0.43-0.93 p = 0.022). The DFS rate at 3 years was 17% in the neo-mFOLFIRINOX group and 11% in the adj-gem group (p = 0.02). On surgical pathological specimen review, the neo-mFOLFIRINOX group had statistically (p < 0.05) lower tumor grade, lower rates of perineural invasion and lymphovascular invasion, lower pathological T stage, lower pathological N stage, and lower number of nodes positive compared to the adj-gem group. Frequencies of obtaining R0 resections were higher in the neo-mFOLFIRINOX versus adj-gem groups but not statistically different (51.9% vs 40.4, p = 0.2). The average age and performance status were similar between the two groups. Conclusions: At our institution, BR and UR pancreatic cancer patients who received neo-mFOLFIRINOX and completed resection had longer OS, DFS, and more favorable pathological indicators compared to those patients who had upfront surgery and adjuvant gemcitabine. Randomized clinical trials comparing neoadjuvant versus adjuvant FOLFIRINOX are needed to validate these findings.

Association of liver-directed local therapy with overall survival in metastatic intrahepatic cholangiocarcinoma

e15659

Background: Intrahepatic cholangiocarcinoma (ICC) is an aggressive hepatobiliary malignancy characterized by local infiltration and lymph node, lung, and bone metastases. The majority of patients die from tumor-related liver failure. The standard of care for metastatic ICC is chemotherapy (CHT) and the role of local therapy to the liver is unclear. We used the National Cancer Database (NCDB) to compare overall survival (OS) of patients treated with CHT, with and without local radiotherapy (RT) or surgery of the liver. Methods: We evaluated patients with metastatic ICC who received CHT with or without hepatic surgery or external beam RT to a dose ≥ 45 Gy. We used multiple imputation followed by cox proportional hazards and nearest neighbor propensity score matching (1:1, caliper = 0.1) on the basis of age, sex, race, comorbidity score, T-stage, tumor size, N-stage, primary tumor focality, primary tumor vascular invasion, year of diagnosis, insurance status, and treatment facility, as well as presence of bone, lung, and lymph node metastases. Results: We identified 2201 patients who received either CHT alone (n = 2097), or with hepatic surgery (n = 76) or RT (n = 28). Liver-directed local therapy was associated with improved OS on univariate (hazard ratio [HR] = 0.57; 95% CI 0.15 - 0.71; p < 0.001) and multivariate analysis (HR = 0.61; 95% CI 0.49 - 0.75; p < 0.001). There was no difference in OS between RT versus surgery (HR = 1.37; 95% CI 0.76 - 2.46; p = 0.30). After propensity score matching, there were 104 patients in each cohort. Liver therapy continued to be associated with improved OS (HR = 0.60; 95% CI 0.45 - 0.81; p = 0.001). Conclusions: We found that addition of local therapy to the liver with surgery or RT is associated with higher OS when compared to CHT alone in metastatic ICC. These findings should be validated in an independent cohort.

Fractional CO2 laser therapy for genitourinary syndrome of menopause (GSM) in survivors of breast cancer (BC)

202

Background: Fractional CO2 laser therapy is an emerging treatment for GSM. The objective of this study was to determine the feasibility, tolerability and preliminary efficacy of fractional CO2 laser therapy in BC survivors. Methods: This was a single arm feasibility study of BC survivors with dyspareunia and/or vaginal dryness. Participants received three treatments with office-based fractional CO2 laser on at least 30 day intervals and returned for a one-month follow-up. Feasibility was defined as treatment completion without serious adverse events (SAE) in a minimum of 80% of patients. Primary efficacy was evaluated using the mean change (∆) in the score on the Vaginal Assessment Scale (VAS). Secondary efficacy endpoints included mean ∆ in scores on the Female Sexual Function Index (FSFI) and Urogenital Distress Inventory (UDI). Descriptive statistics (means and 95% confidence intervals (CI) for continuous variables and proportions for categorical variables) were used. Results: The study is ongoing with 65 patients enrolled. To date, 37 patients have completed all study treatments and follow-up. Median age for those who have completed treatment was 57 years (range 34-72). Most were ER/PR positive (78%) and Her 2 negative (81%) with stage I (43%) or II (41%) BC. Ninety-five percent were receiving endocrine therapy, most commonly aromatase inhibitors (73%). No SAEs were reported in the 37 patients who have completed study treatments and their outcomes are as follows. Based on the VAS, 78% reported moderate-severe dyspareunia and 89% reported moderate-severe vaginal dryness at baseline. At follow up, 28% reported moderate-severe dyspareunia and 28% reported moderate-severe vaginal dryness. The VAS score improved from baseline to follow up (mean ∆ 4.1; 95% CI [3.1, 5.1]). Similarly, the FSFI score improved (mean ∆ -10.0; 95% CI [-13.2, -6.9]) and the UDI score improved (mean ∆ -5.7; 95% CI [-10.1, -1.3]). Final efficacy analysis will be reported once all patients have completed all time points. Conclusions: Fractional CO2 laser treatment is feasible and tolerable in BC survivors and may reduce symptom burden from GSM. A randomized controlled trial with sham laser is currently in development. Clinical trial information: NCT03307044.

Phase Ib Results of the Rational Combination of Selumetinib and Cyclosporin A in Advanced Solid Tumors with an Expansion Cohort in Metastatic Colorectal Cancer

MEK inhibition is of interest in cancer drug development, but clinical activity in metastatic colorectal cancer (mCRC) has been limited. Preclinical studies demonstrated Wnt pathway overexpression in KRAS-mutant cell lines resistant to the MEK inhibitor, selumetinib. The combination of selumetinib and cyclosporin A, a noncanonical Wnt pathway modulator, demonstrated antitumor activity in mCRC patient-derived xenografts. To translate these results, we conducted a NCI Cancer Therapy Evaluation Program-approved multicenter phase I/IB trial (NCT02188264) of the combination of selumetinib and cyclosporin A. Patients with advanced solid malignancies were treated with the combination of oral selumetinib and cyclosporin A in the dose escalation phase, followed by an expansion cohort of irinotecan and oxaliplatin-refractory mCRC. The expansion cohort utilized a single-agent selumetinib "run-in" to evaluate FZD2 biomarker upregulation and KRAS-WT and KRAS-MT stratification to identify any potential predictors of efficacy. Twenty and 19 patients were enrolled in dose escalation and expansion phases, respectively. The most common adverse events and grade 3/4 toxicities were rash, hypertension, and edema. Three dose-limiting toxicities (grade 3 hypertension, rash, and increased creatinine) were reported. The MTD was selumetinib 75 mg twice daily and cyclosporin A 2 mg/kg twice daily on a 28-day cycle. KRAS stratification did not identify any differences in response between KRAS-WT and KRAS-MT cancers. Two partial responses, 18 stable disease, and 10 progressive disease responses were observed. Combination selumetinib and cyclosporin A is well tolerated, with evidence of activity in mCRC. Future strategies for concept development include identifying better predictors of efficacy and improved Wnt pathway modulation.Significance: These findings translate preclinical studies combining selumetinib and cyclosporin into a phase I first-in-human clinical trial of such a combination in patients with advanced solid malignancies. Cancer Res; 78(18); 5398-407. ©2018 AACR.

Abstract A69: Efficacy of alternative 28-day capecitabine dosing schedule in metastatic breast cancer

Background: The approved dosing schedule of capecitabine monotherapy in metastatic breast cancer (MBC) is 1250 mg/m2/dose administered days 1 through 14 of a 21-day cycle, but many patients (pts) have difficulty with this schedule due to side effects. Use of a lower starting dose such as 1000 mg/m2/dose or use of an alternative 28-day administration schedule (7 day on, 7 day off, repeat) allows for greater tolerability. Given limited data regarding efficacy of the alternative 28-day schedule, the primary objective of this study was to compare the efficacy of different schedules of capecitabine in patients with MBC.

Methods: A retrospective chart review of pts with metastatic breast cancer who received capecitabine as monotherapy between 2002 and 2014 at the Ohio State University James Cancer Hospital was performed. We excluded any HER2-positive patients who had received concurrent HER2-targeted therapy. Pts who initiated therapy at a dose of 1000 mg/m2/dose were classified by these dosing schedules: Arm A (21 day), B (28 day), and C (changeover from 21 day to 28 day). Time to treatment failure (TTF) and overall survival (OS) were compared between dosing schedules using Kaplan Meier curves and log-rank tests.

Results: A total of 181 MBC patients (Arm A: n = 113, Arm B: n = 25, Arm C: n = 43) with the following patient characteristics met eligibility criteria; 86.2% Caucasians, 13.8% non-Caucasians, 64.64% estrogen receptor (ER)-positive, 3.31% ER positive/HER2-positive, 2.22% ER negative/HER2-positive, and 29.83% triple-negative. The HER2-positive patients were excluded as they received concurrent therapy. A significant difference was seen in TTF (Arm A: 2.7 mo, Arm B: 2.8 mo, Arm C: 7.1 mo, p = 0.001) when comparing all dosing schedules as well as in OS (Arm A: 5.7 yrs, Arm B: 9.6 yrs, Arm C: 7.8 yrs, p = 0.006). After an initial dose reduction, patients on Arm B tolerated capecitabine for a longer period of time than patients on Arm A before needing a second dose reduction (Table 1). The median time on capecitabine for Arm A was 11.9 weeks and 12.6 weeks for Arm B, and the mean time of both Arm A and Arm B on capecitabine was 22.2 weeks. Patients with ER-positive breast cancer had improved TTF (4.45 months vs 2.32 months, p &lt; 0.001) and OS (7.26 years vs 3.99 years, p &lt; 0.001) compared to ER-negative breast cancer. Caucasians had improved TTF compared to African Americans (AA) and other races (3.90 mo vs 2.87 mo, p = 0.004); however, there was no significant difference in OS.

Median starting dose (mg/m2): Arm A - 1000; Arm B - 1043; Arm C - 1000

Time to 1st dose reduction (weeks): Arm A - 6; Arm B - 6; Arm C - 6.5

Dose after 1st reduction (mg/m2): Arm A - 808; Arm B - 848.5; Arm C - 802

Time to 2nd dose reduction (weeks): Arm A - 6; Arm B - 20; Arm C - 8

Dose after 2nd reduction (mg/m2): Arm A - 599.5; Arm B - 690; Arm C - 697

Time to 3rd dose reduction (weeks): Arm A - 6; Arm B - 0; Arm C - 24

Dose after 3rd reduction (mg/m2): Arm A - 575; Arm B - 0; Arm C - 557

Table 1: Median dose (mg/m2) and median time to reductions (in weeks)

Conclusions: Our study shows that patients who received the 28-day cycle initially or who were switched to the 28-day cycle appeared to have improved TTF and OS compared to patients on the 21-day cycle. It also shows that AA women had worse TTF on capecitabine when compared to Caucasians. One hypothesis for the improved TTF and OS is that this could be due to a higher total dose of capecitabine received in Arm B and C as shown in Table 1. We acknowledge that the limitations of our study include the sample size and the retrospective nature, and that further work needs to be done. However, the 28-day dosing schedule for capecitabine could be an alternative for elderly patients or patients with poor performance status who are at higher risk for drug toxicities.

Citation Format: Nicole Olivia Williams, Anupama Suresh, Julie Stephens, Marilly Palettas, Michael J. Berger, Akaansha Ganju, Raquel Reinbolt, Robert Wesolowski, Anne M. Noonan, Jeffrey Bryan VanDeusen, Sagar Sardesai, Maryam Lustberg, Maryam B. Lustberg, Bhuvaneswari Ramaswamy. Efficacy of alternative 28-day capecitabine dosing schedule in metastatic breast cancer [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr A69.