PM577 advancing into clinic for Wilson Disease

Research evidence excerpt

PM577 advancing into clinic for Wilson Disease

Update

June 18, 2026 02:02 PM GMT

Morgan Stanley & Co. LLCMPrime Medicine Inc | North America Terence C Flynn, Ph.D.

Equity Analyst

PM577 advancing into clinic for Terence.Flynn@morganstanley.comDamien H Kerner +1 212 761-2230

Research Associate

Damien.H.Kerner@morganstanley.com +1 212 761-3829

Wilson Disease Chris Yu, J.D., Ph.D.

Chris.L.Yu@morganstanley.com +1 212 761-2535

PRME reported that PM577a's clinical trial application for Wilson Disease (WD;

Connor M Massari

rare genetic disorder where the body cannot eliminate excess copper) was Equity Analyst

cleared by New Zealand's medical authority (LINK), marking the company's first Connor.Massari@morganstanley.com +1 212 761-2417

Alexander Yevdokimov, Ph.D.

clinical authorization for an in vivo prime editing therapy. We see this as an Research Associate

expected positive for the stock. Alexander.Yevdokimov@morganstanley.com +1 212 761-2167

Hailey Horowitz

PRME plans to initiate the PM577a Ph1/2 trial in 2H26 and expects initial POC Research Associate

Hailey.Horowitz@morganstanley.com +1 212 761-5264

data in 2027. The trial is a global, open-label, study to evaluate the safety and

Morgan Stanley India Company Private Limited+

efficacy of PM577a across ascending doses. Efficacy assessments may include

Saket Agarwal

copper efflux, serum ceruloplasmin, non-ceruloplasmin bound copper, 24-hour Research Associate

urinary copper excretion, and hepatic copper biopsy. Saket.Agarwal@morganstanley.com +91 22 6995-4012

The company hosted a KOL call in November to review PM577's preclinical data and Prime Medicine Inc (PRME.O, PRME US)

the WD treatment landscape (see our takeaways HERE). The KOL highlighted Biotechnology | United States of America