Prime Medicine announced positive initial clinical trial data for PM359, a prime-edited cell therapy for Chronic Granulomatous Disease (CGD). The first patient dosed showed a significant increase in NADPH oxidase activity, exceeding the threshold for clinical benefit, and rapid cell engraftment. Prime Medicine is now seeking external partners to continue PM359’s clinical development while focusing on its in vivo liver programs.
This news represents a significant advancement in gene editing. It’s the first clinical data demonstrating the successful application of prime editing in humans, validating the technology’s potential to correct disease-causing mutations and offer curative therapies for genetic disorders. The rapid engraftment observed with PM359, nearly twice as fast as approved gene editing therapies, suggests a potential advantage in patient recovery and treatment efficacy. This success could accelerate the development of other prime editing therapies, particularly for diseases like CGD that currently lack effective treatments.
The first patient dosed achieved 58% DHR positivity by Day 15 and 66% by Day 30, surpassing the 20% target indicative of clinical benefit. Neutrophil and platelet engraftment occurred on Days 14 and 19 respectively, significantly faster than comparable gene editing therapies. No serious adverse events related to PM359 were reported. Prime Medicine is seeking external partners to advance PM359 and will focus its internal efforts on in vivo liver programs for Wilson’s Disease and Alpha-1 Antitrypsin Deficiency, as well as a Cystic Fibrosis program and CAR-T cell therapies.
This early success suggests a promising future for prime editing technology. The positive clinical data strengthens the case for further investment and research in this field, potentially leading to new treatments for a broad range of genetic diseases. While the future development of PM359 will rely on external partnerships, the positive initial data significantly de-risks the program and increases its attractiveness to potential collaborators, ultimately increasing the likelihood of this therapy reaching patients in need.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
