Cabozantinib and Panitumumab for RAS Wild-Type Metastatic Colorectal Cancer.

LESSONS LEARNED: Antitumor activity was observed in the study population. Dose modifications of cabozantinib improve long-term tolerability. Biomarkers are needed to identify patient populations most likely to benefit. Further study of cabozantinib with or without panitumumab in patients with metastatic colorectal cancer is warranted. BACKGROUND: The epidermal growth factor receptor (EGFR) antibody panitumumab is active in patients with RAS wild-type (WT) metastatic colorectal cancer (mCRC), but nearly all patients experience resistance. MET amplification is a driver of panitumumab resistance. Cabozantinib is an inhibitor of multiple kinases, including vascular endothelial growth factor receptor 2 (VEGFR2) and c-MET, and may delay or reverse anti-EGFR resistance. METHODS: In this phase Ib clinical trial, we established the maximum tolerated dose (MTD) and recommended phase II dose (RP2D) of cabozantinib and panitumumab. We then treated an expansion cohort to further describe the tolerability and clinical activity of the RP2D. Eligibility included patients with KRAS WT mCRC (later amended to include only RAS WT mCRC) who had received prior treatment with a fluoropyrimidine, oxaliplatin, irinotecan, and bevacizumab. RESULTS: Twenty-five patients were enrolled and treated. The MTD/RP2D was cabozantinib 60 mg p.o. daily and panitumumab 6 mg/kg I.V. every 2 weeks. The objective response rate (ORR) was 16%. Median progression free survival (PFS) was 3.7 months (90% confidence interval [CI], 2.3-7.1). Median overall survival (OS) was 12.1 months (90% CI, 7.5-14.3). Five patients (20%) discontinued treatment due to toxicity, and 18 patients (72%) required a dose reduction of cabozantinib. CONCLUSION: The combination of cabozantinib and panitumumab has activity. Dose reductions of cabozantinib improve tolerability.

Using a geriatric oncology assessment to link with services (GOAL).

OBJECTIVE: Geriatric screening tools assess functional limitations and inform clinical decision-making for older adults with cancer. Our objective was to evaluate the feasibility and effectiveness of a screener in community-based oncology clinics. MATERIALS AND METHODS: Eligible patients were from two rural, underserved community-based cancer clinics; within 12 months of a cancer diagnosis (breast, lung, colorectal, pancreas, esophageal); aged ≥60 years; and not exclusively pursuing palliative care. We used a previously validated tool that was embedded in the electronic health record (EHR). Patient-reported responses identified memory impairment, depressive symptoms, deficits in activities of daily living, poor nutrition, and polypharmacy. At the discretion of the oncologist, responses prompted service referrals. From the EHR, we extracted information about referrals and completion of planned therapy. We present descriptive statistics. RESULTS: Enrolled patients (n = 44) had a mean age of 71.5 years (SD = 6.9). Most were non-white (61%), women (66%), with government-sponsored health insurance (80%). The most commonly identified geriatric syndromes: polypharmacy (89%), reduced quality of life (39%), and poor nutrition (39%). The screener triggered a referral in 98% of patients. Generated referrals were for depressive symptoms (52% needed, 39% received), nutrition (43% needed, 37% received), and polypharmacy (89% needed, 26% received). Patients were referred to social work (56%), nutrition (44%), and pharmacy (25%). Many patients completed planned radiation therapy (100%), surgery (70%), and chemotherapy (60%). CONCLUSIONS: Use of an EHR-embedded brief geriatric oncology assessment in rural oncology clinics identified geriatric syndromes that would benefit from provision of services in nearly all enrolled patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02906592.