BioXcel Therapeutics Announces Promising Top-Line Results from Phase 2 Trial of BXCL701 in Aggressive Form of Rare Prostate Cancer

BioXcel Therapeutics Announces Promising Top-Line Results from Phase 2 Trial of BXCL701 in Aggressive Form of Rare Prostate Cancer

Results demonstrate encouraging response rate of BXCL701 plus KEYTRUDA® (pembrolizumab) in patients with SCNC

Full data will be presented at the 2023 ASCO Genitourinary Cancers Symposium in February

NEW HAVEN, Conn., Jan. 11, 2023 (GLOBE NEWSWIRE) -- BioXcel Therapeutics, Inc. (Nasdaq: BTAI), a biopharmaceutical company utilizing artificial intelligence approaches to develop transformative medicines in neuroscience and immuno-oncology, today announced promising top-line data from its Phase 2 trial of BXCL701, the Company's investigational, oral innate immune activator, in combination with KEYTRUDA® (pembrolizumab) in small cell neuroendocrine metastatic castration-resistant prostate cancer (SCNC) patients. Full data have been submitted to the 2023 American Society of Clinical Oncology Genitourinary Cancers Symposium (ASCO GU).

“We are pleased that BXCL701 in combination with pembrolizumab has demonstrated an encouraging response rate in this difficult-to-treat cancer with no currently approved FDA therapies,” said Vincent J. O’Neill, M.D., Chief R&D Officer, OnkosXcel Therapeutics, a wholly owned subsidiary of BioXcel Therapeutics. “BXCL701’s promising profile as an oral innate immune activator with a large safety dataset and novel mechanism of action further supports OnkosXcel’s pipeline and use of BioXcel’s AI platform, and reinforces our confidence in BXCL701’s potential to enable checkpoint inhibitor therapy in traditionally cold cancers.”

SCNC represents a rare, underserved, growing patient population, with SCNC cases increasing due to earlier and more widespread use of androgen receptor inhibitors. In 2022, there were an estimated 268,5001 new prostate cancer patients, with approximately 10,740 patients progressing to SCNC.

The Phase 2a trial is an open-label, multicenter study to evaluate the safety and efficacy of BXCL701 in combination with pembrolizumab in men with SCNC. Eligibility criteria include histologically confirmed de novo or treatment-emergent SCNC, progression as defined by PCWG3 criteria, and at least 1 prior line of chemotherapy for locally advanced or metastatic prostate cancer. 28 evaluable SCNC patients received 0.3 mg of BXCL701 twice daily (BID) on days 1 through 14 of a 21-day cycle (0.2 mg BID the first week of Cycle 1) plus 200 mg of pembrolizumab administered intravenously on day 1 and every subsequent 21 days. The primary endpoint of the trial is a composite response rate defined as RECIST 1.1 and/or PSA50 and/or CTC count conversion. Secondary endpoints include duration of response, progression-free survival, overall survival, and biomarker evaluation as measured by changes in circulating cytokines and correlation of outcome with baseline tumor characteristics.