Based on the results of the nonrandomized multicenter phase II VERSATILE-002 trial reported in JAMA Oncology, a regimen adding the human papillomavirus type 16 (HPV16)-targeted immunotherapy PDS0101 to pembrolizumab demonstrated antitumor activity in immune checkpoint inhibitor–naive patients with recurrent or metastatic HPV16-positive head and neck squamous cell carcinoma. Weiss et al also reported a manageable safety profile.
“The [findings] support advancement into confirmatory testing in the first-line setting,” the investigators wrote.
Study Details
The study enrolled 88 patients with histologically confirmed recurrent or metastatic HPV16-positive head and neck squamous cell carcinoma across 26 oncology centers in the United States, United Kingdom, and Ireland. Patients received 200 mg of intravenous pembrolizumab every 3 weeks for up to 35 cycles plus 5 protocol-scheduled subcutaneous doses of PDS0101.
The safety population comprised 87 patients who received at least one treatment dose. Efficacy was assessed in a modified intention-to-treat population of 75 patients, including 53 (70.7%) who were immune checkpoint inhibitor–naive with a PD-L1 combined positive score of at least 1 and 22 (29.3%) who were immune checkpoint inhibitor–resistant. A Simon’s two-stage optimal design was applied separately to the immune checkpoint inhibitor–naive and –resistant cohorts.
The primary endpoint was objective response rate, as assessed by masked independent central review. Secondary endpoints included progression-free survival, overall survival, and safety.
Key Findings
An objective response rate of 34.0% by central review was reported among immune checkpoint inhibitor–naive patients in the modified intention-to-treat cohort. Median progression-free and overall survival were 5.3 and 39.3 months, respectively.
The primary endpoint was not met in the immune checkpoint inhibitor–resistant subgroup of the modified intention-to-treat cohort, with no objective responses observed. Median progression-free survival was 2.0 months, and median overall survival was 14.8 months.
According to the investigators, the treatment was well tolerated. A total of 13.8% of patients experienced a grade 3 or higher treatment-related adverse event.
“The results of this nonrandomized clinical trial validate the potential of PDS0101 to enhance antitumor immunity when administered with immune checkpoint inhibitor therapy in the first-line recurrent or metastatic setting,” the investigators concluded.
Jared Weiss, MD, of The University of North Carolina at Chapel Hill Lineberger Comprehensive Cancer Center, is the corresponding author of the article in JAMA Oncology.
DISCLOSURE: The study was funded by PDS Biotechnology and Merck Sharp & Dohme. For full disclosures of the study authors, visit jamanetwork.com.
