A phase II study (AARDVARC) of AZD4635 in combination with durvalumab and cabazitaxel in patients with progressive, metastatic, castration-resistant prostate cancer

• Published in: ESMO open 2024-06, Vol.9 (6), p.103446, Article 103446
• Main Authors: Alonso-Gordoa, T., Goodman, M., Vulsteke, C., Roubaud, G., Zhang, J., Parikh, M., Piulats, J.M., Azaro, A., James, G.D., Cavazzina, R., Gangl, E.T., Thompson, J., Pouliot, G., Kumar, R., Sweeney, C.
• Format: Article
• Language: English
• Subjects: AZD4635; cabazitaxel; durvalumab; metastatic castration-resistant prostate cancer; Original Research; pharmacokinetics; safety
• ISSN: 2059-7029; 2059-7029
• DOI: 10.1016/j.esmoop.2024.103446

This phase II nonrandomized study evaluated the efficacy and safety of AZD4635 in combination with durvalumab (Arm A) or durvalumab plus cabazitaxel (Arm B) in patients with metastatic castration-resistant prostate cancer (mCRPC) previously treated with docetaxel and ≥1 novel hormonal agent. The primary endpoint was radiographic progression-free survival (rPFS) per RECIST v1.1 (soft tissue) or the Prostate Cancer Clinical Trials Working Group 3 (bone). Secondary endpoints included safety, tolerability, overall survival, confirmed prostate-specific antigen (PSA50) response, pharmacokinetics, and objective response rate. Enrollment in Arm A was stopped following a sponsor decision unrelated to safety. The study was stopped based on the planned futility analysis due to low PSA50 response in Arm B. In the final analysis (1 November 2021), 30 patients were treated (Arm A, n = 2; Arm B, n = 28). The median rPFS in Arm B was 5.8 months (95% confidence interval 4.2-not calculable). Median rPFS was 5.8 months versus 4.2 months for patients with high versus low blood-based adenosine signature. The most common treatment-related adverse events in Arm B were nausea (50.0%), diarrhea (46.4%), anemia and neutropenia (both 35.7%), asthenia (32.1%), and vomiting (28.6%). Overall, AZD4635 in combination with durvalumab or AZD4635 in combination with cabazitaxel and durvalumab showed limited efficacy in patients with mCRPC. Although the safety profile of both combinations was consistent with known safety data of the individual agents, the results of this trial do not support further development of the combinations. •AZD4635 is a novel adenosine2A receptor antagonist that blocks A2aR-mediated signaling in tumor-infiltrating immune cells.•Adding cabazitaxel to the AZD4635 plus durvalumab combination may enhance antitumor activity in the post-docetaxel setting.•AZD4635 in combination with durvalumab or durvalumab plus cabazitaxel showed limited efficacy in patients with mCRPC.•AZD4635 in combination with durvalumab or cabazitaxel was generally well tolerated.•Adenosine signature signaling score may assist with optimal patient selection for adenosine pathway modulators.