The combination had a 24-month OS rate of 80%.
The universal cancer vaccine UV1 in combination with pembrolizumab (Keytruda) is safe and produces a strong clinical response in patients with metastatic melanoma, according to phase 1 findings announced in a press release by Ultimovacs ASA.1
The observed clinical efficacy and safety of the combination met the primary end point of a phase 1 open-label, multicenter study (NCT03538314).
“The combination of UV1 and pembrolizumab has a strong safety profile and provides a prolonged and effective clinical response in advanced melanoma,” said Jens Bjørheim, MD, PhD, chief medical officer of Ultimovacs, in a press release. “These two-year follow-up data suggest that the way in which UV1 mobilizes the immune system provides patients with lasting benefits.
The study has an actual enrollment of 30 participants and an estimated completion data of October 2022. The primary end point of the study is the number of patients with treatment-related adverse events up to week 29. Secondary end points include tumor response up to week 52 as accessed by RECIST and iRECIST and overall survival (OS).2
During the single-arm study, all patients received UV1 and pembrolizumab for 14 weeks initially. At the time of the October 12, 2021 data cutoff, every patient had been followed for at least 24 months from the start of their treatment.
In the first cohort of 20 patients, the 2-year OS was 80%, with a median progression-free survival (PFS) of 18.9 months. This is longer than the OS and PFS of the phase 3 KEYNOTE-006 (NCT01866319), which evaluated pembrolizumab monotherapy compared to ipilimumab (Yervoy) in patients with advanced melanoma.3 In that study, the 24-month OS was 58% and a median PFS of 5.5-11.6 months.
At the 12-month mark, the OS was 85%. No unexpected safety issues related to either the vaccine or pembrolizumab were reported.4
In order to participate in the phase 1 study, patients must have stage IIIB, IIIC, or IV melanoma and previously untreated with and eligible for pembrolizumab. Patients with uveal or ocular malignant melanoma, a history of hematologic or primary solid tumor malignancies, prior systemic treatment for unresectable or metastatic melanoma with the exception of BRAF and MEK inhibitors, or a history of cardiac disease are not eligible to participate.
“We believe that UV1 will play a transformative role in the treatment of solid tumors, elevating patients’ response rates in combination with checkpoint inhibitors and providing long-term clinical benefits.” said Carlos de Sousa, chief executive officer of Ultimovacs, in a press release. “We look forward to sharing more detailed results of this ongoing study at a major clinical oncology meeting in 2022.”