AskBio Applauds Commencement of Pfizer’s Pivotal Trial for Duchenne Muscular Dystrophy

Pfizer initiates first Phase 3 gene therapy trial for DMD based on AskBio’s technology and clinical studies initiated in 2006 

On January 7, 2021, Pfizer announced that the first patient had been dosed in its Phase 3 pivotal study of PF-06939926, an investigational gene therapy for Duchenne muscular dystrophy (DMD). Its CIFFREO study is the first gene therapy product to enter Phase 3 clinical studies for DMD, a rare genetic disease that causes progressive muscle weakness and affects young boys almost exclusively. Most patients with DMD typically lose the ability to walk by age 12 and die of cardiac or respiratory failure by their mid-20s.

“We’re honored to have played an early role in developing the technology and clinical program behind this study and celebrate this historic milestone for DMD patients and their families,” said Jude Samulski, PhD, AskBio co-founder and Chief Scientific Officer. “We believe gene therapy holds great promise for patients suffering from devastating diseases like DMD, and we congratulate Pfizer on bringing this potentially curative therapy one step closer to them.”

The CIFFREO study is one of many milestones to validate the groundbreaking gene therapy work of AskBio’s scientific co-founders, Drs. Jude Samulski and Xiao Xiao, since the company was founded in 2001. The technology behind PF-06939926 involves an AAV vector carrying a unique mini-dystrophin transgene cassette generated by Dr. Xiao. In 2006, AskBio initiated the first-ever clinical trial for gene therapy in boys with DMD in collaboration with Nationwide Children’s Hospital.

Pfizer acquired the therapeutic platform to treat DMD when it purchased AskBio subsidiary, Bamboo Therapeutics, in August 2016. The acquisition expanded Pfizer’s expertise in gene therapy by providing clinical and several pre-clinical assets and industry-leading capabilities in recombinant adeno-associated virus (AAV) vector design and manufacturing.

Pfizer licensed AskBio’s Pro10™, an industry-leading proprietary cell line manufacturing process, to successfully complete Bamboo’s Phase 1 studies, with promising results reported in 2019.

To learn more about the fascinating story behind gene therapy for DMD, listen to Dr. Samulski’s recent interview with PharmaTalk Radio.

AskBio is at the forefront of the gene therapy industry with an extensive gene therapy platform that includes a pipeline of clinical-stage therapeutics, streamlined manufacturing processes, an extensive capsid library and a rich portfolio of AAV-related intellectual property. The company is committed to bringing effective therapies to market, reducing the cost of production and increasing access with innovative technology for advancing gene therapy development.

About Gene Therapy

Gene therapy is an emerging area of genetic medicine focused on highly specialized, one-time, transformative treatments addressing the root cause of diseases caused by genetic mutation. Gene therapy uses modified viruses or other technologies to deliver therapeutic genes to cells or tissues to address genetic diseases at their source. One of the most exciting advances in modern medicine has been discovering how AAV can be used as an effective delivery system for therapeutic genetic material into living tissue. AAV gene therapy has broad therapeutic implications for a vast array of diseases and has become the dominant delivery vector across the industry. 

About AskBio
Founded in 2001, Asklepios BioPharmaceutical, Inc. (AskBio), a wholly owned and independently operated subsidiary of Bayer AG acquired in 2020, is a fully integrated AAV gene therapy company dedicated to developing life-saving medicines that cure genetic diseases. The company maintains a portfolio of clinical programs across a range of neuromuscular, central nervous system, cardiovascular and metabolic disease indications with a clinical-stage pipeline that includes therapeutics for Pompe disease, Parkinson’s disease and congestive heart failure, as well as out-licensed clinical indications for hemophilia and Duchenne muscular dystrophy. AskBio’s gene therapy platform includes Pro10™, an industry-leading proprietary cell line manufacturing process, and an extensive AAV capsid and promoter library. With global headquarters in Research Triangle Park, North Carolina, and European headquarters in Edinburgh, UK, the company has generated hundreds of proprietary third-generation AAV capsids and promoters, several of which have entered clinical testing. An early innovator in the space, the company holds more than 500 patents in areas such as AAV production and chimeric and self-complementary capsids. Learn more at or follow us on LinkedIn.