Pfizer Opens First US Phase 3 Study Evaluating Gene Therapy
After FDA placed a clinical hold on the gene therapy study in December 2021, the agency noted that Pfizer has addressed its request related to the potency assay and will open the first US sites.
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By - Pfizer will open the first United States sites in the Phase 3 study evaluating its investigational mini-dystrophin gene therapy, fordadistrogene movaparvovec, in ambulatory patients with Duchenne muscular dystrophy (DMD).
The global Phase 3 study, CIFFREO, has been ongoing in 11 countries. But in December 2021, officials paused the study to implement a protocol amendment following a fatal serious adverse event that occurred in a Phase 1b study in the non-ambulatory cohort.
The patient in the study had more advanced disease with underlying cardiac dysfunction. But Pfizer paused screening, randomization, and dosing in all gene therapy studies as the independent external Data Monitoring Committee (eDMC) reviewed the data, and FDA placed the IND on clinical hold.
Notably, the agency recently stated that Pfizer had addressed its request related to the potency assay. To date, regulatory authorities in the UK, Canada, Taiwan, Spain, and Belgium approved the re-start of the Phase 3 study, and additional global reviews are ongoing.
Pfizer anticipates that nearly all CIFFREO sites will open by June 2022.
“Duchenne muscular dystrophy is a devastating disease with very limited treatment options, and we believe that gene therapy has the potential to significantly impact disease progression,” Brenda Cooperstone, chief development officer of rare disease at Pfizer Global Product Development, said in the announcement.
“Pfizer is pleased to progress CIFFREO and is working as quickly as possible to activate trial sites as local regulatory and ethics approvals occur. We thank the participants in our clinical trials and their families, as well as the broader Duchenne community, for their ongoing trust and collaboration as we work to advance our investigational gene therapy,” Cooperstone continued.
In September 2021, Pfizer announced that it submitted a protocol amendment to the ongoing Phase 3 trial of fordadistrogene movaparvovec.
Across all of the company’s studies, three serious adverse events have occurred, leading Pfizer to amend the current protocol. But the trial continued to recruit a total of 99 patients who fit the amended protocol.
