We are devastated to learn of the tragic loss of a young boy that was participating in Pfizer’s Phase 2 DAYLIGHT study. This study is evaluating the safety and dystrophin expression of fordadistrogene movaparvovec (PF-06939926), Pfizer’s gene therapy candidate for Duchenne, in boys who are two and three years old.

According to the company, “We do not yet have complete information and are actively working with the trial site investigator to understand what happened.” Pfizer has indicated that the individual received the investigational gene therapy in early 2023. Additionally, “Initial dosing for the placebo-controlled, randomized Phase 3 CIFFREO trial, which utilizes a crossover trial design, was also completed in 2023. We have decided to pause dosing associated with the cross-over portion of CIFFREO, and we are working with regulators and the independent external Data Monitoring Committee as we learn more about this event. Other than this pause in dosing, trial activities are continuing as scheduled,” Pfizer stated.

The company issued a community letter sharing this devastating news and that it is committed to sharing more information as it becomes available. We anticipate additional updates from Pfizer as the company’s investigation continues. 

Our hearts ache for this family, and this loss underscores the critical importance of understanding what transpired to ensure the safety of all individuals participating in clinical trials. As a community, it is imperative that we come together to support each other during this time and work collectively towards making advancements in research while prioritizing safety above all else.  

A Note From PPMD’s Pat Furlong

As a community, we are bound together by shared experiences, hopes, and aspirations. In times like these, we draw strength from each other, offering support, solace, and empathy. The loss of any member of our community is deeply felt, and our hearts ache with the family and loved ones of this courageous young child, whose bravery and commitment to advancing research for Duchenne will forever be remembered and honored.

This journey is not without its challenges, and yet, it is also instilled with resilience, determination, and unwavering hope. In the face of adversity, we find the courage to persevere, fueled by the knowledge that every step forward brings us closer to our shared goal of ending Duchenne.

We grieve this loss. There are no words to describe the unjust nature of a tragedy like this. Let us come together in this time of mourning, holding this Duchenne community near and dear as our hearts feel hollow and our minds search for answers.

To the family and loved ones of this precious young boy, please know that you are not alone. Your loss is deeply felt by the entire Duchenne community, and we are here to offer our unwavering support and comfort during this difficult time.