The phase 2 registration trial designed to evaluate ImmunoPulse IL-12 in combination with pembrolizumab for unresectable metastatic melanoma showed an increase in response rates among patients who were not expected to respond to anti–PD-1 therapy alone.
ImmunoPulse IL-12 (OncoSec Medical) is an intratumoral immunotherapy platform that delivers DNA-based interleukin-12.
The single-arm, open-label trial evaluated the combination of ImmunoPulse IL-12 with pembrolizumab (Keytruda, Merck), a PD-1 checkpoint inhibitor, in patients with stage III/IV melanoma who had a low likelihood of responding to an anti–PD-1 therapy based on their tumor biomarkers (CD8–positive tumor infiltrating lymphocytes < 22% PD-1hiCTLA-4+).
Key endpoints included best overall response rate, safety and tolerability, duration of response, 24-week landmark PFS, median PFS and OS.
Patients treated with the combination demonstrated an ORR of 43% at 24 weeks and best ORR of 48%.
In total, 24% of patients achieved complete response, 19% had partial response and 9% demonstrated stable disease, for a total disease control rate of 52%.
The combination demonstrated a favorable safety profile and was well tolerated.