-- IND and CTA clearances in the United States and New Zealand establish a global Phase 1/2 program for PM577a in Wilson disease; study startup activities underway, with initial clinical data in 2027 --
-- Favorable arbitration resolution with Beam Therapeutics affirms Prime Medicine's rights to PM647 in Alpha-1 Antitrypsin Deficiency; IND and/or CTA submission expected in 3Q 2026, with initial clinical data in 2027 --
-- FDA grants Regenerative Medicine Advanced Therapy designation to PM359; continued regulatory engagement with the FDA toward a BLA submission for PM359 in 1H 2027 --
-- Cash, cash equivalents, investments, and restricted cash of $108.8 million as of June 30, 2026, providing cash runway into 2027 --
CAMBRIDGE, Mass., Aug. 06, 2026 (GLOBE NEWSWIRE) -- Prime Medicine, Inc. (Nasdaq: PRME), a biotechnology company committed to delivering a new class of differentiated one-time curative genetic therapies, today reported financial results for the quarter ended June 30, 2026 and provided a business update.
"We have continued to deliver on the focused strategy we laid out last year," said Allan Reine, M.D., Chief Executive Officer of Prime Medicine. "Wilson disease is now cleared to enter the clinic in two geographies. Our rights in Alpha-1 Antitrypsin Deficiency are secure, and the program is advancing toward regulatory submission. And in CGD, where Prime Editing has already shown it can correct disease in humans, we are working toward a BLA filing, and delivering this therapy to patients in need. The opportunity ahead of us is to demonstrate that same potential effect in vivo, in two of the largest genetic diseases targeting the liver."
Dr. Reine continued, "We are now entering a transformative phase of growth and value creation potential that extends well beyond this year. We expect to initiate our global Phase 1/2 study of PM577a in the second half of 2026 and to submit an IND and/or CTA for PM647 in the third quarter, with initial clinical data from both programs anticipated in 2027. Alongside our progress toward a potential BLA for PM359, these milestones have the potential to significantly expand the clinical evidence supporting Prime Editing and advance our goal of bringing the first Prime Editing therapies to patients."
Prime Medicine's Pipeline:
Prime Medicine is advancing in vivo programs to cure two of the largest genetic diseases originating in the liver, Wilson disease $(WD)$ and Alpha-1 Antitrypsin Deficiency (AATD). Following clearance of the Company's Investigational New Drug $(IND)$ application in the United States and Clinical Trial Application $(CTA)$ in New Zealand, PM577a is progressing into a global Phase 1/2 program and study startup activities are underway. Additionally, Prime Medicine expects to submit an IND and/or CTA for PM647 in AATD in the third quarter of 2026. Initial clinical data from both programs are expected in 2027.
Prime Medicine is also advancing an in vivo Cystic Fibrosis $(CF)$ program with support from the Cystic Fibrosis Foundation and Prime Edited CAR-T products for hematology, immunology and oncology in partnership with Bristol Myers Squibb. Additionally, following positive proof-of-concept data from the first two patients treated in its Phase 1/2 study of PM359 for the treatment of chronic granulomatous disease (CGD), and the recent grant of Regenerative Medicine Advanced Therapy (RMAT) designation, Prime Medicine continues to engage in regulatory dialogue with the U.S. Food and Drug Administration (FDA) toward a potential Biologics License Application (BLA) filing for PM359.
Recent Corporate Updates:
Wilson Disease (PM577a)
In June 2026, the New Zealand Medicines and Medical Devices Safety Authority (Medsafe) cleared the Company's CTA for PM577a, the first clinical authorization for an in vivo Prime Editing therapy from Prime Medicine. In July 2026, the FDA cleared the Company's IND application for PM577a, opening participation to patients in the United States, where the ATP7B H1069Q variant that PM577a targets is the single most common cause of WD.
Together, the two clearances establish a global Phase 1/2 program. The open-label, first-in-human study will evaluate the safety, tolerability, biological activity and efficacy of ascending doses of PM577a in adults and adolescents with WD, initially enrolling adults who are clinically stable on standard-of-care therapy. Prime Medicine has initiated study startup activities, with initial clinical data anticipated in 2027.
Alpha-1 Antitrypsin Deficiency (PM647)
In July 2026, Prime Medicine announced a positive, binding resolution of its previously disclosed arbitration with Beam Therapeutics, Inc. relating to the parties' 2019 Collaboration and License Agreement. The Tribunal declared that PM647 is within Prime Medicine's "Field" as defined by the agreement, that Prime Medicine did not breach the agreement, and that Prime Medicine owes no monetary damages.
PM647 leverages Prime Medicine's universal liver lipid nanoparticle (LNP) to correct the E342K (PiZ) mutation in the SERPINA1* gene, the most prevalent disease-causing mutation in AATD. In fully humanized mouse models, treatment with PM647 achieved high levels of editing efficiency and restored the corrected protein isoform (M-AAT) into the healthy human range at clinically relevant doses.
PM647 is built on the same universal liver LNP delivery approach that underpins PM577a. Prime Medicine expects to draw on its experience with PM577a as it advances PM647 toward the clinic, and to benefit from the efficiencies and learnings enabled by its modular approach. Prime Medicine expects to submit an IND and/or CTA for PM647 in the third quarter of 2026, with initial clinical data expected in 2027.
Chronic Granulomatous Disease (PM359)
In June 2026, the FDA granted RMAT designation to PM359 based on Phase 1/2 clinical data, including data previously published in The New England Journal of Medicine. RMAT provides the benefits of intensive FDA guidance and expedited review, including discussions on surrogate or intermediate endpoints that may support accelerated approval and eligibility for rolling and priority review of a future BLA.
PM359 has now received RMAT, Fast Track, Orphan Drug, and Rare Pediatric Disease designations from the FDA. Prime Medicine continues to engage with the FDA on the most efficient path to a BLA submission planned for the first half of 2027.
Upcoming Milestones
-- Continue study startup activities for the global Phase 1/2 clinical trial
of PM577a in WD, initial clinical data in 2027.
-- Submission of an IND and/or CTA for PM647 in AATD in the third quarter of
2026, initial clinical data in 2027.
-- Continued regulatory engagement with the FDA toward a BLA submission for
PM359 in the first half of 2027.
Second Quarter 2026 Financial Results
-- Research and Development (R&D) Expenses: R&D expenses were $33.4 million
for the three months ended June 30, 2026, as compared to $41.4 million
for the three months ended June 30, 2025. The decrease in R&D expenses
was driven primarily by fewer R&D personnel-related costs resulting from
the workforce reduction announced in May 2025, and facility cost savings
realized from bringing the Company's vivarium in-house.
-- General and Administrative (G&A) Expenses: G&A expenses were
$11.0 million for the three months ended June 30, 2026, as compared to
$13.1 million for the three months ended June 30, 2025. The decrease in
G&A expenses was primarily driven by a decrease in personnel costs
resulting from one-time severance charges recorded in Q2 2025 and a
decrease in stock compensation expense, and lower corporate legal fees.
-- Net Loss: Net loss was $42.1 million for the three months ended June 30,
2026, as compared to $52.6 million for the three months ended June 30,
2025.
-- Cash Position: As of June 30, 2026, cash, cash equivalents, investments,
and restricted cash were $108.8 million, as compared to $191.4 million as
of December 31, 2025.
Financial Guidance
Based on its current operating plans, Prime Medicine expects that its cash, cash equivalents and investments as of June 30, 2026 will be sufficient to fund its operating expenses and capital expenditure requirements into 2027.
About Prime Medicine
Prime Medicine is a leading biotechnology company dedicated to creating and delivering the next generation of gene editing therapies to patients. The Company is deploying its proprietary Prime Editing platform, a versatile, precise and efficient gene editing technology, to develop a new class of differentiated one-time curative genetic therapies. Designed to make only the right edit at the right position within a gene while minimizing unwanted DNA modifications, Prime Editors have the potential to repair almost all types of genetic mutations and work in many different tissues, organs and cell types. Taken together, Prime Editing's versatile gene editing capabilities could unlock opportunities across thousands of potential indications.
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