A Phase 1 Study of Cabozantinib and Trifluridine/Tipiracil in Metastatic Colorectal Adenocarcinoma.

INTRODUCTION: This study determined the safety and recommended phase 2 dose (RP2D) of the multikinase inhibitor cabozantinib in combination with trifluridine/tipiracil (FTD/TPI) in refractory metastatic colorectal carcinoma (mCRC). PATIENTS AND METHODS: Single institution investigator-initiated phase 1 study using 3+3 design. Eligible mCRC patients had received prior standard regimens. Cabozantinib was given orally (p.o.) at 20 mg (dose level [DL] 0) or 40 mg (DL 1) daily on days 1-28, and FTD/TPI p.o. at 35 mg/m2 on days 1-5 and 8-12 every 28 days. Prophylactic growth-factor support was allowed. RESULTS: Fifteen patients were enrolled. Median age 56 years (31-80), male (12/15), ECOG 0/1 = 9/6. Three patients were treated at DL 0 and another nine were treated at DL 1, none exhibiting a DLT. Most common any grade (G) treatment related adverse events (TRAE) were diarrhea (50%), nausea (42%), neutropenia (42%), fatigue (33%), and rash (25%). G3-4 TRAE were neutropenia (25%) and thrombocytopenia, hypokalemia, and weight loss (each 8%). No serious TRAE or G5 were reported. The RP2D was determined to be DL 1. Median PFS was 3.8 months (95% CI 1.9-6.8) and disease control rate was 86.7%. CONCLUSION: The combination of cabozantinib and FTD/TPI is feasible and tolerable at standard doses with the use of growth factors and showed encouraging clinical activity in refractory mCRC. CLINICALTRIALS: GOV: NCT04868773.

Age-dependent overall survival benefit of androgen deprivation therapy for metastatic prostate cancer.

BACKGROUND: Androgen deprivation therapy (ADT) remains a standard of care in metastatic prostate cancer. Recent prospective trials have explored addition of chemotherapy to ADT. We retrospectively examined overall survival in metastatic prostate cancer patients treated with ADT, chemotherapy plus ADT (C + ADT), or observation from 2004 to 2010 using National Cancer Database data. METHODS: Using the National Cancer Database, 21,977 patients with metastatic prostate cancer diagnosed from 2004 to 2010 were identified. Multivariate logistic regression, Kaplan-Meier survival analysis and Cox proportional hazards regression modeling were implemented, with overall survival as the primary endpoint. RESULTS: Five-year overall survival was 13.6% in patients aged ≥ 75 years vs. 30.1% (age 65-74) and 34.5% (age 18-64). Subgroup analysis of age-based cohorts (<65 and ≥65 years) showed poor overall survival for C + ADT vs. ADT alone, both in younger (HR 1.35, 95% CI 1.21-1.50; p < 0.0001) as well as older (HR 1.21, 95% CI 1.08-1.34; p = 0.0006) populations. Younger patients had no significant difference in overall survival for observation vs. ADT (HR 0.99, 95% CI 0.92-1.08; p = 0.9121). Besides age, other factors impacting overall survival included race, rural/urban settings, comorbidity score, income, PSA and radiation. DISCUSSION: Younger patients had no significant difference in overall survival between observation or ADT. This implies a group of younger patients in whom ADT does not confer any overall survival benefit. Future clinical trials with genetic and biologic markers are needed to delineate which subgroups would not benefit from C + ADT or ADT alone. This is of utmost clinical importance given the negative impact of ADT on quality of life and comorbidities.