OncoSec announced the initiation of patient dosing in PISCES/KEYNOTE-695, the company's global, multi-center, registration-directed open-label Phase 2b clinical trial. The trial will evaluate the combination of ImmunoPulse IL-12 (intratumoral pIL-12 [tavokinogene telseplasmid or tavo] with electroporation), and pembrolizumab in patients with unresectable metastatic melanoma who have progressed or are progressing on an anti-PD-1 therapy.
"There remains a significant unmet medical need in oncology for patients in whom the existing PD-1 therapies do not work. Based on the encouraging data we presented at SITC, we believe the combination of ImmunoPulse IL-12 and pembrolizumab may offer a differentiated approach to reshaping the tumor microenvironment by converting immunologically cold tumors to hot," said Sharron Gargosky, Chief Clinical and Regulatory Officer of OncoSec. "We look forward to the continued advancement of this trial and to sharing data in 2018."
The Phase 2b, multicenter study of intratumoral tavo with electroporation in combination with intravenous pembrolizumab will enroll approximately 48 patients with a histological diagnosis of melanoma with progressive locally advanced or metastatic disease defined as Stage III or Stage IV. The primary endpoint will be the Best Overall Response Rate (BORR).
The company's prior Phase 2 OMS I-102 combination study of ImmunoPulse IL-12 and pembrolizumab in 22 patients unlikely to respond to anti-PD-1 therapy demonstrated a 50% best overall response rate and a 41% complete response rate. In addition, the trial showed a 57% progression free survival (PFS) rate at 15 months (median PFS not yet reached) and 100% (11/11) duration of response. In clinical studies to date, intratumoral tavo has demonstrated a favorable safety profile and has been well tolerated.
PISCES/KEYNOTE-695 is the second combination study conducted with pembrolizumab and, if successful, could form the basis for a BLA under the accelerated approval pathway.