Prime Medicine, Inc. Common Stock

Prime Medicine announced a positive, binding resolution to its arbitration with Beam Therapeutics over their 2019 Collaboration and License Agreement. The Tribunal declared that PM647, the company's investigational Prime Editing drug for Alpha-1 Antitrypsin Deficiency, falls within Prime Medicine's defined field under the agreement, meaning Prime Medicine did not breach the agreement and owes no monetary damages to Beam Therapeutics. PM647 uses a universal liver lipid nanoparticle to correct the E342K mutation in the SERPINA1 gene, the most common disease-causing mutation in AATD, and has shown high editing efficiency and restored healthy-range protein levels in fully humanized mouse models at clinically relevant doses.

H.C. Wainwright upgraded Prime Medicine to Buy from Neutral with an $8 price target after New Zealand’s Medicines and Medical Devices Safety Authority accepted the clinical trial application for PM577a, the company’s investigational therapy for Wilson’s disease. The firm called the clearance a meaningful de-risking event, noting it marks the first clinical authorization for an in vivo prime editing therapy from Prime Medicine. The clearance, announced on June 18, 2026, enables a global Phase 1/2 study in adults and adolescents with Wilson Disease, with proof-of-concept data expected in 2027. Separately, on June 22, 2026, the FDA granted Regenerative Medicine Advanced Therapy designation to PM359, the company’s stem cell therapy for p47phox-deficient chronic granulomatous disease, based on Phase 1/2 data published in The New England Journal of Medicine.

Prime Medicine has received clearance from New Zealand's Medsafe for its Clinical Trial Application for PM577a, an investigational Prime Editing therapy targeting the H1069Q mutation in Wilson disease. This is the company's first clinical authorization for an in vivo Prime Editing therapy, allowing a global Phase 1/2 study to begin in the second half of 2026. The trial will assess safety, tolerability, and biological activity in adults and adolescents, with initial clinical data expected in 2027. PM577a is designed as a one-time therapy that corrects the genetic root cause of Wilson disease, a disorder caused by ATP7B gene mutations leading to copper buildup. Prime Medicine also noted its modular lipid nanoparticle delivery platform may enable expansion into additional mutations, including R778L, which is more common in East Asian populations.