Exelixis Announces Phase 1b Results from Cohort 6 of COSMIC-021 Trial in Patients with Metastatic Castration-Resistant Prostate Cancer
Exelixis (NASDAQ: EXEL) announced results from cohort 6 of the COSMIC-021 trial, focusing on cabozantinib combined with atezolizumab for metastatic castration-resistant prostate cancer (CRPC). The trial included 132 patients, with a primary endpoint of objective response rate (ORR). High-risk patients showed an ORR of 27%, with a disease control rate of 88%. No new safety signals were observed, and treatment discontinuation due to adverse events was 12%. Exelixis plans to discuss FDA regulatory submission next, following the encouraging results.
- High-risk patients showed a 27% objective response rate (ORR).
- Disease control rate was 88%, indicating strong potential for the treatment.
- No new safety signals identified; the treatment profile was consistent with known safety profiles.
- None.
Exelixis, Inc. (NASDAQ: EXEL) today announced results from the metastatic castration-resistant prostate cancer (CRPC) cohort 6 of COSMIC-021, the phase 1b trial of cabozantinib (CABOMETYX®) in combination with atezolizumab in patients with locally advanced or metastatic solid tumors. Cohort 6 included patients with metastatic CRPC who had been previously treated with enzalutamide and/or abiraterone acetate.
Upon enrollment, patients had to have measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST v. 1.1) per investigator assessment, had progressed on prior novel hormonal therapy, and could have received prior docetaxel for hormone-sensitive disease. The analysis included 132 patients, 101 of whom had high-risk disease, defined as measurable visceral and/or extra-pelvic lymph node metastases. The group with high-risk disease is the patient population for which Exelixis would pursue a U.S. regulatory filing. The median follow-up for the high-risk patients was 15.8 months. The primary endpoint was investigator-assessed objective response rate (ORR) per RECIST v. 1.1.
In the high-risk population, the investigator-assessed ORR was
An interim analysis of the initial 44 patients enrolled in the cohort was previously presented at the 2020 American Society of Clinical Oncology Virtual Scientific Program.
“These results from cohort 6 of COSMIC-021 suggest cabozantinib in combination with atezolizumab holds promise as a potential new treatment option in metastatic castration-resistant prostate cancer, a difficult-to-treat tumor type that typically has a poor prognosis,” said Neeraj Agarwal, M.D., Professor of Medicine, Huntsman Cancer Institute, University of Utah and an investigator of the trial. “There is a significant need for more options beyond chemotherapy once patients progress on androgen-deprivation therapy, so it is encouraging to see the response rates, disease control and tolerable safety profile associated with cabozantinib in combination with atezolizumab in this trial.”
The adverse event profile observed in the study was reflective of the known safety profile for each single agent. No new safety signals were identified in this expanded combination cohort. Discontinuation of treatment due to adverse events unrelated to disease progression was
In continuation of prior regulatory interaction and feedback from the U.S. Food & Drug Administration (FDA), Exelixis intends to discuss the results with the FDA to determine next steps toward a regulatory submission for the combination regimen for patients with high-risk metastatic CRPC. The global phase 3 trial, CONTACT-02, initiated enrollment in June 2020 and is evaluating cabozantinib in combination with atezolizumab versus a second novel hormonal therapy in patients with metastatic CRPC who have been previously treated with one novel hormonal therapy.
“Many patients with metastatic castration-resistant prostate cancer who have progressed on a novel hormonal therapy wish to avoid or delay chemotherapy. These results of the COSMIC-021 cohort 6 suggest the combination of cabozantinib and atezolizumab may offer this patient population a new treatment option,” said Gisela Schwab, M.D., President, Product Development and Medical Affairs and Chief Medical Officer, Exelixis. “We look forward to building on these results with the phase 3 CONTACT-02 trial in our continued effort to bring cabozantinib to many more patients in need.”
More information about this trial (NCT03170960) is available at ClinicalTrials.gov.
About the COSMIC-021 Study
COSMIC-021 is a multicenter, phase 1b, open-label study that is divided into two parts: a dose-escalation phase and an expansion cohort phase. The dose-escalation phase was designed to enroll patients either with advanced renal cell carcinoma (RCC) with or without prior systemic therapy or with inoperable, locally advanced, metastatic or recurrent urothelial carcinoma (UC), (including renal, pelvis, ureter, urinary bladder an
FAQ
What are the COSMIC-021 trial results for cabozantinib combined with atezolizumab?
What is the primary endpoint of the COSMIC-021 trial?
What is the significance of the 27% objective response rate in the trial?
What are the next steps for Exelixis following these trial results?
What was the patient population included in the COSMIC-021 cohort 6?
