Alligator Bioscience announces positive 18-month follow-up data from the OPTIMIZE-1 Phase 2 study of the company's lead asset mitazalimab in 1st line metastatic pancreatic cancer. The open-label, multi-center study assessed the safety and efficacy of mitazalimab (CD40 mAb agonist) in combination with standard of care chemotherapy mFOLFIRINOX, in previously untreated, chemotherapy naïve pancreatic cancer patients. The data demonstrated a near doubling of the 18-month survival rate to 36.2% in patients treated with mitazalimab in combination with mFOLFIRINOX, compared to 18.6% reported with FOLFIRINOX alone.

The updated Median Overall Survival (mOS) was 14.9 months, up from 14.3 months at the time of first analysis, comparing favorably to the 11.1 months demonstrated by FOLFIRINOX and more recently by NALIRIFOX. Median follow-up duration for the updated analysis was 18.2 months, indicating the maturity of these outcomes. At the time of the analysis, a total of 17 (30%) patients were still alive, and of these 9 (16% overall) were still on treatment.

The longest ongoing treatment duration was 24 months. The follow-up data further demonstrate: An additional late responding patient increased the confirmed Objective Response Rate (ORR; as per the Response Evaluation Criteria in Solid Tumors RECIST 1.1) to 42.1% from the 40.4% reported in the top-line readout, comparing favorably to the ORR of 31.6% reported in a similar patient population treated with FOLFIRINOX alone and an ORR of 42% reported by NALIRIFOX. An increase in the unconfirmed ORR to 54.4% was reported in 57 evaluable patients.

The median Duration of Response (DoR) was 12.6 months, an unprecedented outcome in this aggressive disease and much longer compared to 5.9 months with FOLFIRINOX and 7.3 months with NALIRIFOX. Median Progression Free Survival (PFS) was 7.7 months, and a nearly 3-fold increase in the 12-month PFS rate was reported; 35.1% in OPTIMIZE-1 against 12.1% previously reported for FOLFIRINOX.