Massarelli E, et al. - Researchers investigated if the effectiveness of nivolumab (an anti–programmed cell death 1 [PD-1] immune checkpoint antibody) can be increased when it is given in combination with ISA 101 (a synthetic long-peptide human papilloma virus [HPV]-16 vaccine inducing HPV-specific T cells) in patients with incurable HPV-16–positive cancer. Findings demonstrated that combining nivolumab and ISA 101 resulted in overall response rate of 33% and median overall survival of 17.5 months, which is encouraging vs PD-1 inhibition alone in similar patients.

Methods

• This was a single-arm, single-center phase 2 clinical trial, in which 24 patients with incurable HPV-16–positive cancer were enrolled from December 23, 2015 to December 12, 2016, with follow-up for censored patients for 12.2 months through August 31, 2017.
• Participants were administered the vaccine ISA101, 100 μg/peptide, subcutaneously on days 1, 22, and 50.
• Participants also received nivolumab, 3 mg/kg, intravenously every 2 weeks beginning day 8 for up to 1 year.
• They assessed the overall response rate (per Response Evaluation Criteria in Solid Tumors, version 1.1), indicating effectiveness.

Results

• The estimated overall response rate was 33% (8 patients; 90% CI, 19%-50%) among 24 patients (4 women and 20 men; 22 with oropharyngeal cancer; median age, 60 years [range, 36-73 years]).
• According to data, the median duration of response was 10.3 months (95% CI, 10.3 months to inestimable) and 5 of 8 patients remained in response.
• Median progression-free survival and median overall survival was 2.7 months (95% CI, 2.5-9.4 months) and 17.5 months (95% CI, 17.5 months to inestimable), respectively.
• They reported grades 3 to 4 toxicity in 2 patients (asymptomatic grade 3 transaminase level elevation in 1 patient and grade 4 lipase elevation in 1 patient), requiring nivolumab therapy be discontinued.