Young boy DIES in Pfizer’s trial for gene therapy against Duchenne muscular dystrophy

05/23/2024 / By Ava Grace

Pfizer’s trial for a gene therapy against Duchenne muscular dystrophy (DMD) has been halted following the death of one participant – a young boy.

According to Great Game India, the boy’s death was revealed in a recent letter from the New York-based drug giant. The boy had received the gene therapy in early 2023, but the details surrounding his death are still unclear. Pfizer is actively working with investigators to understand what happened.

The trial known as Daylight aimed to study the effects of Pfizer’s experimental gene therapy against DMD called fordadistrogene movaparvovec on boys aged two to three years old. DMD is a rare genetic disease that primarily affects boys, causing progressive muscle degeneration. If successful, Pfizer’s gene therapy could offer hope for those affected by this condition.

According to the National Institutes of Health, DMD is one of the most severe forms of genetic muscular dystrophy. The Muscular Dystrophy Association explains that the condition is characterized by progressive muscle degeneration and weakness, which are caused by alterations to a protein called dystrophin. This protein helps keep muscle cells intact, it adds.

Symptoms of DMD are typically exhibited early on in childhood around the age of two and three, and include difficulty jumping, running and walking as well as enlargement of the calves, a waddling gait, and an inward curve of the spine. As the disease progresses, DMD can impact the heart and respiratory muscles leading to impaired pulmonary function, which can eventually cause acute respiratory failure.

The condition primarily affects boys, with an estimated one in every 3,500 male births impacted worldwide.

In 2021, Pfizer revealed that a young male participant had died in the non-ambulatory cohort of its Phase 1b mini-dystrophin gene therapy trial for DMD. As a result of that 2021 death, the Food and Drug Administration placed the company’s Investigational New Drug (IND) Application on clinical hold before lifting it in April 2022.

Pfizer pauses trial for its DMD gene therapy

Following news of the recent death, Pfizer has paused dosing for part of another trial dubbed CIFFREO. This second trial, which involves young male participants afflicted with DMD aged four up to eight years old, has been halted as a precautionary measure. But other trials evaluating the gene therapy will continue as planned, according to the Epoch Times. (Related: Drug approvals by regulators are often based on poor clinical data, researchers find).

“On behalf of everyone at Pfizer, we extend our sympathies to his family, friends and those closest to his care,” the drug maker said in the community letter, which was made public by the nonprofit advocacy group Parent Project Muscular Dystrophy.

“The safety and well-being of the patients in our clinical trials remains our top priority, and we are committed to sharing more information with the medical and patient community as soon as we can. We are also aware that many in the patient community are hopeful about the potential benefit of fordadistrogene movaparvovec for the treatment of DMD, and we will continue to collect data from our trials to evaluate its ability to address this disease.”

News of the boy’s death comes after Mikael Dolsten, Pfizer’s chief scientific officer and president of research, touted fordadistrogene movaparvovec during the company’s third-quarter 2023 earnings call in October.

“I think our gene therapy for DMD [has] shown a very consistent effect across biomarkers and functional end points. This makes our gene therapy, in a way, the main game in town,” he said at the time. According to Dolsten, functional data the company had reported up until that point had given “encouraging signals in both the younger and the slightly older boys.”

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Watch this clip from “Worldview Report” about Pfizer offering condolences for the sudden death of the young boy in its DMD gene therapy trial.

This video is from the Worldview Report channel on Brighteon.com.