Prime Medicine Unveils Broad Gene Editing Applications at ASGCT24

Prime Medicine, a biotech firm, has recently unveiled its ambitious plans for next-generation gene editing therapies at the American Society of Gene & Cell Therapy's annual conference in Baltimore. The company has just received FDA approval for a clinical trial involving a prime editing candidate aimed at treating a rare disease, marking a significant milestone in the field of genetic medicine.
During a workshop focused on the advancement and delivery methods of precision genome editing, Prime Medicine showcased preclinical findings that highlight the vast potential of their prime editing technology. This innovative approach utilizes CRISPR to correct faulty genes without causing breaks in the DNA double helix. Jonathan Levy, the company's lead scientist in platform delivery innovation, stated that prime editors are capable of addressing nearly all genetic mutations and are effective across various tissues, organs, and cell types, offering opportunities for thousands of different conditions.
Levy emphasized that the prime editing process has a very low rate of off-target editing, with no detectable off-targets in their leading programs. The technology, first introduced in a 2019 Nature publication, has since been enhanced with the addition of dual-flap prime editors for larger genetic modifications and PASSIGE, a system designed to integrate sizable genetic payloads using a recombinase target sequence. Prime Medicine is actively developing a range of therapeutic programs for conditions in hematology, immunology, liver, lung, ocular, and neuromuscular areas.
On April 29, Prime Medicine announced that the FDA had cleared a study for a drug candidate based on their prime editing platform, signifying the first human application of this genetic technology. The company anticipates reporting initial results from the Phase I/II trial of PM359 next year. PM359 is an ex vivo candidate developed to correct a common disease-causing mutation associated with chronic granulomatous disease, a rare inherited hematologic disorder.
The company is exploring various delivery methods, including electroporation, lipid nanoparticles (LNPs), and adeno-associated viruses (AAVs). Prime Medicine is particularly interested in novel LNPs, utilizing a proprietary library of over 800 lipids to develop these delivery systems. The goal is to create a universal LNP that can be applied across multiple therapeutic areas.
In January 2024, Prime Medicine received a $15 million grant from the Cystic Fibrosis Foundation to aid in the development of prime editors for the treatment of cystic fibrosis (CF). The company aims to use "hotspot editing" and PASSIGE to provide a single superexon insertion strategy that could potentially restore CFTR expression in lung cells under natural conditions for nearly all individuals with CF, regardless of their specific CFTR mutation.