FibroGen, Inc. announced graduation and completion of the pamrevlumab experimental arm in the Pancreatic Cancer Action Network's (PanCAN) Precision PromiseSM Phase 2/3 adaptive platform trial, which evaluates pamrevlumab in combination with the chemotherapy treatments gemcitabine and nab-paclitaxel for patients with metastatic pancreatic ductal adenocarcinoma (mPDAC). Topline data from this registration study is anticipated in the second quarter of 2024. Pamrevlumab, in Stage 1 of the trial, achieved a protocol pre-specified = 35% predictive probability of success for the primary endpoint of overall survival at the completion of the trial, and thus graduated to the second and final Stage of the trial in the third quarter of 2022.

Pamrevlumab is the first experimental arm to meet its required threshold for graduation to Stage 2 in the adaptive platform trial. The pamrevlumab arm of the study completed Stage 2 of the trial in January 2024. PanCAN?s Precision PromiseSM adaptive platform trial (NCT04229004) is a U.S.-based, seamless Phase 2/3 study that enrolled patients in approximately 24 sites around the country.

The multi-arm study consists of experimental treatment arms and two comparator arms: gemcitabine + nab-paclitaxel and mFOLFIRINOX. The pamrevlumab experimental arm was offered to patients with mPDAC as either a first-line (1L) or second-line (2L) treatment option. In the initial stage of the study (Stage 1), at least 100 patients with mPDAC received pamrevlumab in combination with gemcitabine and nab-paclitaxel.

Guided by Bayesian principles, the graduation threshold for pamrevlumab was a protocol pre-specified = 35% predictive probability of success for the primary endpoint of overall survival at the completion of the trial. Upon graduation, an additional 75 patients with mPDAC were enrolled (Stage 2), receiving the same pamrevlumab treatment regimen as in Stage 1. All patients are dosed until disease progression and the final analysis is based upon the data collected up to 12 months after the last patient initiates treatment in Stage 2. The combined Stage 1 and Stage 2 data will form the basis for analysis of the primary and secondary endpoints for the pamrevlumab arm. Secondary endpoints include progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR), offering a comprehensive understanding of the treatment's impact.

Biomarker-related data, including genomics data, have been collected to provide additional insights into the trial's outcomes. Precision PromiseSM is a registration study and the statistical design has been discussed by PanCAN with the FDA. The statistical design of Precision PromiseSM is led by renowned statistician Dr. Donald Berry of Berry Consulting.