PDS Biotechnology Corporation announced promising interim data from the VERSATILE-002 (NCT04260126) Phase 2 clinical trial investigating PDS0101 in combination with Merck's anti-PD-1 therapy, KEYTRUDA (pembrolizumab), in patients with unresectable, recurrent or metastatic human papillomavirus (HPV)16-positive head and neck cancer. The results will be featured in a poster presentation and in a head and neck cancer expert panel discussion at the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting being held June 2-6 in Chicago. In measuring the efficacy of PDS0101 in combination with KEYTRUDA, the abstract highlights the following interim data: Estimated 12-month overall survival rate was 87.1%.

Published results are 36-50% with approved ICIs used alone. Median progression-free survival was 10.4 months (95% CI 4.2, 15.3). Published results are median PFS of 2-3 months for approved ICIs when used as monotherapy in patients with similar PD-L1 levels.

A disease control rate (disease stabilization or tumor shrinkage) of 70.6% (24/34) Confirmed and unconfirmed objective response rate was 41.2% (14/34 patients), which is identical to the preliminary response rate data PDS Biotech previously reported at ASCO 2022 (7/17 patients). To date these responses have been confirmed in nine of the 34 patients (26.5%), including one complete response. 15/34 patients (44.1%) had stable disease.

9/34 patients (26.5%) had progressive disease. 4/48 (8.3%) of patients had a Grade 3 treatment-related adverse event (TRAE). No Grade 4 or higher TRAEs were observed.

VERSATILE-002 is a Phase 2, open-label, multicenter study of the efficacy and safety of PDS0101 administered in combination with KEYTRUDA® in adults with HPV16-positive unresectable, recurrent or metastatic HNSCC. VERSATILE-002 is investigating two patient populations of HPV16-positive head and neck cancer patients whose cancer has returned or spread. Interim data from the first group, which had not been previously treated with an ICI (ICI naïve), is the focus of the ASCO poster presentation and follow-up discussion among a panel of head and neck cancer experts.

The second group of patients had previously failed treatments including ICI therapy (ICI refractory).