Prime Medicine, Inc.

What they do

Prime Medicine develops genetic medicines based on Prime Editing, a Cas9 nickase-reverse transcriptase system guided by a pegRNA that edits DNA without double-stranded breaks. Its wholly owned in vivo programs target liver diseases (PM577a for Wilson disease, PM647 for alpha-1 antitrypsin deficiency) and cystic fibrosis, supported by the Cystic Fibrosis Foundation. Partnered ex vivo work with Bristol-Myers Squibb applies Prime Editing to T-cell engineering, and the ex vivo PM359 program for chronic granulomatous disease has reported restoration of functional protein activity in treated patients.

Revenue drivers

• Collaboration revenue (BMS) — Payments under the Bristol-Myers Squibb ex vivo T-cell engineering collaboration; annual revenue was $4.6M in 2025 and $3.0M in 2024, so collaboration funding is the only reported revenue line.
• Cystic Fibrosis Foundation support — The CF program is conducted with support from the Cystic Fibrosis Foundation, providing funding for that in vivo program.
• PM577a (Wilson disease) — Lead wholly owned in vivo program targeting the ATP7B H1069Q mutation; IND cleared in the U.S. and CTA cleared in New Zealand, but no product revenue is reported.
• PM647 (AATD) and PM359 (CGD) — PM647 for alpha-1 antitrypsin deficiency and PM359 for chronic granulomatous disease are clinical/regulatory stage; neither generates revenue.

Recent performance

Revenue was minimal and collaboration-based: $4.6M for full-year 2025, and quarterly revenue of $1.5M, $1.1M, $1.2M and $0.8M across 2025. Net loss was $201.1M in 2025 versus $195.9M in 2024, and operating cash flow was negative $162.6M in 2025. As of June 30, 2026, total assets were $249.0M, total liabilities $209.2M, shareholders' equity $39.8M, and cash and equivalents $47.5M. The company also reports cash, cash equivalents, investments and restricted cash of $108.8M as of June 30, 2026, which it says funds operations into 2027.

Strategy

Management says it is executing a focused strategy centered on in vivo liver programs (Wilson disease and AATD) plus the ex vivo PM359 CGD program. The company has cleared an IND in the U.S. and a CTA in New Zealand for PM577a, establishing a global Phase 1/2 program with study startup underway. It expects to submit an IND and/or CTA for PM647 in the third quarter of 2026 following a favorable arbitration resolution with Beam Therapeutics affirming its PM647 rights. It continues FDA dialogue toward a potential BLA for PM359 in the first half of 2027, and is advancing a CF program with Cystic Fibrosis Foundation support and Prime Edited CAR-T work with BMS.

Risks

• No product revenue and recurring losses — Net loss was $201.1M in 2025 with an accumulated deficit of $888.4M as of December 31, 2025, and the company expects losses to continue for the foreseeable future.
• Going-concern / capital needs — Shareholders' equity was $39.8M and cash and equivalents $47.5M at June 30, 2026, with total liabilities of $209.2M, and the company states its reported liquidity funds operations only into 2027.
• Early-stage clinical and regulatory risk — PM577a has only just cleared an IND and CTA with initial clinical data expected in 2027, and PM647 has not yet been submitted; no program has demonstrated efficacy in a controlled trial.
• Reliance on collaborations and platform validation — Revenue to date has come from collaboration payments such as the BMS ex vivo T-cell agreement, and the company must maintain these relationships and validate Prime Editing across tissues.

Outlook

Management expects to initiate the global Phase 1/2 study of PM577a in the second half of 2026, with initial clinical data from PM577a and PM647 anticipated in 2027. It plans to submit an IND and/or CTA for PM647 in the third quarter of 2026 and to continue FDA engagement toward a potential BLA filing for PM359 in the first half of 2027. The company states its $108.8M of cash, cash equivalents, investments and restricted cash as of June 30, 2026 provides runway into 2027.