Pfizer’s CIFFREO Phase 3 study in DMD fails to meet primary endpoint

Pfizer Inc. (NYSE: PFE), a global leader in pharmaceuticals, faced a setback as their CIFFREO Phase 3 study did not meet its primary endpoint. The study aimed to evaluate the effectiveness of the investigational mini-dystrophin gene therapy, fordadistrogene movaparvovec, in improving motor function among ambulatory boys with Duchenne muscular dystrophy (DMD) aged 4 to 7 years.

Study Details and Outcomes

The CIFFREO trial, a global, multicenter, randomized, double-blind, placebo-controlled study, assessed motor function improvements through the North Star Ambulatory Assessment (NSAA) at one year post-treatment. Unfortunately, the results showed no significant improvement in motor function compared to the placebo group. Key secondary outcomes, such as the 10-meter run/walk velocity and time to rise from the floor velocity, also did not demonstrate a significant difference between the treatment and placebo groups.

Pfizer Inc.’s CIFFREO study on gene therapy for Duchenne muscular dystrophy did not meet its primary motor function improvement endpoint.

Safety Profile and Research Integrity

Despite the disappointing outcomes in efficacy, the safety profile of fordadistrogene movaparvovec was manageable, with most adverse events being mild to moderate and serious adverse events generally responding to clinical management. “We are extremely disappointed that these results did not demonstrate the relative improvement in motor function that we had hoped,” commented Dr. Dan Levy, MD, PhD, Development Head for Duchenne muscular dystrophy at Pfizer. He emphasized the commitment to sharing detailed study results at upcoming medical and patient advocacy meetings to enhance future clinical research.

Next Steps in Research

The CIFFREO study is currently on a dosing pause due to a serious adverse event in the earlier Phase 2 DAYLIGHT trial. Pfizer continues to monitor all participants and is evaluating next steps for the program, reflecting their ongoing commitment to understanding and improving care for Duchenne muscular dystrophy.

The outcome of the CIFFREO trial represents a critical moment in the ongoing quest to find effective treatments for DMD. While the results are disappointing, they provide valuable insights that could shape future research strategies in genetic therapies. Pfizer’s transparency and continued research efforts are vital for the DMD community and demonstrate the complexities involved in developing gene therapies.