Exelixis Presents Positive Cabozantinib Plus Atezolizumab Phase 3 Data in mCRPC at ASCO GU 2024

A recent phase 3 study has shown promising results for patients with metastatic castration-resistant prostate cancer (mCRPC). The trial, known as CONTACT-02, investigated the efficacy of cabozantinib combined with atezolizumab versus a second novel hormonal therapy (NHT) in individuals with mCRPC and measurable extra-pelvic soft tissue disease who had previously progressed on one NHT.

The study demonstrated a significant 35% reduction in the risk of disease progression or death among patients treated with the combination therapy. The findings were presented at the American Society of Clinical Oncology 2024 Genitourinary Cancers Symposium, highlighting the potential of this treatment approach for a patient population that has limited options and poor outcomes.

Dr. Neeraj Agarwal, Senior Director for Clinical Research at Huntsman Cancer Institute and the global lead investigator of the trial, emphasized the unmet need for effective treatments for this group of patients. The CONTACT-02 study is notable for being the first phase 3 trial to show a statistically significant improvement in progression-free survival (PFS) with the use of a tyrosine kinase inhibitor and an immune checkpoint inhibitor.

Detailed data revealed that the median PFS was 6.3 months for patients on the combination therapy, compared to 4.2 months for those on the second NHT. Although the overall survival (OS) data did not reach statistical significance at the time of the presentation, a trend towards improvement was observed, with median OS being 16.7 months for the combination therapy versus 14.6 months for the second NHT.

The study also reported that treatment-emergent adverse events occurred in 97% of patients on the combination therapy and 87% of those on the second NHT, with grade 3/4 events occurring in 48% and 23% of patients, respectively. Despite these adverse events, the combination therapy showed a PFS benefit and a trend towards OS benefit across various high-risk subgroups.

Amy Peterson, Executive Vice President, Product Development & Medical Affairs, and Chief Medical Officer at Exelixis, commented on the importance of having a treatment option that can delay disease progression and is widely accessible to patients who may not be able or willing to seek specialized therapies.

The CONTACT-02 study is a global, multicenter, randomized phase 3 trial that included 507 patients. The trial's primary endpoints are PFS and OS, with secondary endpoints including objective response rate. The study is sponsored by Exelixis and co-funded by Ipsen, Roche, and Takeda Pharmaceutical Company Limited.

Exelixis is a company dedicated to advancing cancer care through the development of innovative oncology medicines. The company's flagship product, CABOMETYX (cabozantinib), is already approved for the treatment of various cancer types, including advanced renal cell carcinoma and hepatocellular carcinoma. The positive results from the CONTACT-02 study could potentially expand the use of cabozantinib in combination with atezolizumab for mCRPC patients.

It is important to note that while the combination of cabozantinib and atezolizumab has shown promise in the study, it is not currently an approved treatment for mCRPC. The safety and efficacy of this combination will need to be further evaluated, and discussions with regulatory authorities will be crucial in determining the next steps for this treatment approach.