Ultimovacs ASA announced continuing positive efficacy data in its ongoing U.S.-based phase I clinical trial, UV1-103. The study evaluates the Company's universal cancer vaccine, UV1, in combination with the anti-PD-1 checkpoint inhibitor pembrolizumab, as first-line treatment in advanced non-resectable and metastatic malignant melanoma patients. After the study ended at two years follow up, the protocol was amended to follow patients for overall survival for up to five years.

Three of the patients, all in cohort 1, did not consent to further follow up, changing the number of participating patients in cohort 1 from 20 to 17 after two years. In addition, one patient died within the past year. At the three years cut-off date for patients in the first cohort the three-year overall survival (OS) rate was 71% (12/17).

The trial has shown a consistently high OS rate; in this patient cohort it was 85% (17/20) after one year and 80% (16/20) after two years follow-up. Having already reached its primary endpoint of safety and tolerability, the UV1-pembrolizumab combination continues to demonstrate strong signals of clinical efficacy in both response rates and extended survival. Pembrolizumab is a standard of care for patients with unresectable or metastatic melanoma, based on data from the KEYNOTE-006 trial.

Follow up of first-line patients with metastatic melanoma in that trial showed an overall survival rate of 51% at 36 months. UV1-103 (Cohort 1) Overall Survival Rate % (Patients alive/total): 12 months: 85% (17/20); 24 months: 80% (16/20); 36 months: 71% (12/17) 3 patients declined follow-up post 24 months, 1 patient died. Further data from the UV1-103 study will be presented at the International Congress of the Society for Melanoma Research, October 18, 2022.