PDS announces efficacy threshold achieved for VERSATILE-002 Phase 2 trial

PDS Biotechnology announced the Company achieved the threshold for efficacy as per investigator assessment in Stage 2 of the VERSATILE-002 Phase 2 clinical trial investigating PDS0101 in combination with Merck’s anti-PD-1 therapy, KEYTRUDA, for the treatment of unresectable, recurrent or metastatic human papillomavirus 16-positive head and neck cancer. The achievement of full recruitment of 54 patients in the ICI naive arm was announced in May 2023. The threshold for efficacy, as defined in the clinical protocol, was achieved when 14 out of the 54 immune checkpoint inhibitor naive patients enrolled achieved a confirmed objective response. Additional patients in the trial have yet to undergo imaging evaluation. Per RECIST 1.1, the standard to classify oncologic imaging outcomes in clinical trials, patients are considered to have achieved an objective response when imaging studies document tumor shrinkage of 30% or more. In VERSATILE-002, the primary endpoint requires two consecutive scans 9 to 12 weeks apart, rather than one, to be considered a confirmed objective response. Confirmation with two consecutive scans is not required to achieve an objective response in every clinical trial per RECIST 1.1. At the recent 2023 American Society of Clinical Oncology Annual Meeting, the company presented data showing 9 confirmed responses among 34 evaluable patients. Median progression-free survival of 10.4 months was also presented at the 2023 ASCO Annual Meeting along with a 12-month overall survival rate of 87.1% for patients with a CPSgreater than or equal to1. Additional patients have been assessed since data was presented at the 2023 ASCO Annual Meeting. With these additional data, a total of 14 patients have now achieved a confirmed response to date. The achievement of this endpoint suggests an additive effect of PDS0101 over published results with ICI monotherapy and is based on statistical calculations using the appropriate power and alpha. The primary endpoint in the VERSATILE-002 study is the best overall response of confirmed complete response or confirmed partial response per RECIST 1.1. The key secondary endpoints are progression-free survival, OS at 12 and 24 months, safety, and tolerability. The study utilizes a Simon’s 2-stage optimum design.