Prime Medicine (PRME) Morgan Stanley 22nd Annual Global Healthcare Conference summary

Platform innovation and differentiation

• Prime Editing enables precise gene correction at the endogenous locus, addressing both small and large genetic changes with high efficiency and minimal off-target effects.

• The platform includes proprietary PASSIGE technology for non-viral, multi-kilobase DNA insertion without double-strand breaks.

• Safety profile is a key differentiator, with extensive off-target analysis and no observed off-target edits in advanced programs.

• Modular approach allows rapid adaptation across programs, streamlining regulatory and development processes.

• Continuous innovation is supported by a dedicated team, strong advisory board, and close collaboration with leading academic figures.

Delivery strategies and milestones

• Delivery platforms include ex vivo, lipid nanoparticle (LNP), and AAV approaches, with proprietary modular LNP technology nearing validation.

• Modular LNP system aims to enable efficient gene editing across multiple organs, with liver and lung as key targets.

• Upcoming milestones include non-human primate data on modular LNP efficiency and safety, and potential for redosing.

• Delivery challenges in the lung are being addressed, particularly for cystic fibrosis, with both inhaled and systemic approaches under consideration.

• External partnerships and collaborations supplement internal expertise, especially for AAV and advanced targeting methods.

Lead asset and clinical development

• Lead program PM359 targets chronic granulomatous disease (CGD) with a phase I/II trial; first patient dosing expected about six months after site activation.

• Key endpoints include rapid engraftment, high editing percentage in stem cells, and restoration of enzymatic activity.

• Data readout is planned for next year, with the trial designed for potential conversion to pivotal status pending regulatory discussions.

• Editing threshold for clinical benefit is set at 15-20%, with preclinical models achieving much higher correction rates.

• Initial trial sites are limited due to processing logistics, but expansion is planned for pivotal studies.