1. PM359 shows early efficacy in treating chronic granulomatous disease. 2. Two patients demonstrated rapid and sustained recovery post-treatment. 3. Phase 1/2 trial results emphasize Prime Editing's safety and effectiveness. 4. Data publication in NEJM boosts credibility and visibility. 5. Potential for broader applications across various genetic diseases.
FAQ
Why Bullish?
Positive trial outcomes may attract investors; similar past successes led to stock gains.
How important is it?
Successful trials can lead to increased confidence in PRME's potential equity growth.
Why Long Term?
Phase 1/2 data may pave the path for future approvals and expanded indications.
Prime Medicine Publishes Phase 1/2 Clinical Data for PM359 in NEJM
CAMBRIDGE, Mass., Dec. 07, 2025 (GLOBE NEWSWIRE) -- Prime Medicine, Inc. (Nasdaq: PRME), a biotechnology firm focused on innovative genetic therapies, announced today the publication of its Phase 1/2 clinical data concerning PM359, an investigational autologous hematopoietic stem cell therapy for treating p47phox chronic granulomatous disease (CGD). The findings were featured in the prestigious New England Journal of Medicine (NEJM) and will also be presented at the upcoming 67th American Society of Hematology (ASH) Annual Meeting from December 6-9, 2025, in Orlando, Florida.
Clinical Trial Overview
The published study, titled “Prime Editing for p47-phox Chronic Granulomatous Disease,” details initial findings from two patients enrolled in the Phase 1/2 trial. The primary objectives of the trial were to evaluate safety, biological activity, and preliminary efficacy in both adult and pediatric participants.
- Neutrophil Engraftment: Both patients demonstrated rapid neutrophil engraftment, achieving 69% and 83% dihydrorhodamine-positive (DHR+) neutrophils by Day 30, significantly surpassing the 20% threshold for clinical benefit.
- NADPH Activity Restoration: Durable restoration of NADPH oxidase activity was noted, indicating a promising early clinical benefit.
- Safety Profile: No adverse events related to PM359 were recorded, aligning with prior observations from busulfan-based conditioning.
Patient Outcomes and Efficacy
Both patients had a history of CGD-related complications, including chronic CGD-associated colitis (CAC) and skin infections, prior to the study. Following the infusion of PM359, both patients remained free of new CGD-related complications.
- Patient 1 ceased mesalamine therapy without experiencing any flare-ups of CAC.
- Patient 2 noted a substantial decrease in fecal calprotectin levels, leading to improved chronic CAC symptoms.
These results provide essential evidence for the safety and effectiveness of Prime Editing as a viable treatment for CGD, reinforcing the potential of PRME's PM359 therapy.
Quote from Leadership
“The publication of these first-in-human data underscores Prime Editing’s potential as a next-generation therapeutic platform," stated Dr. Mohammed Asmal, Chief Medical Officer of Prime Medicine. "These findings not only affirm early clinical efficacy but also shed light on Prime Editing’s safety profile and advantages over other gene editing methodologies.”
About Prime Medicine
Prime Medicine is at the forefront of developing next-generation gene editing therapies. Utilizing its proprietary Prime Editing platform, the company aims to provide one-time curative solutions for a variety of genetic disorders. The technology is designed to perform precise edits at specific gene locations while minimizing unwanted mutations.
Prime Medicine is advancing a portfolio of investigational therapies across multiple areas, including liver, lung, immunology, and oncology. The company strategically focuses on high-value programs with well-understood biological mechanisms and clear regulatory pathways, ensuring a strong foundation for future growth and innovation.
Forward-Looking Statements
This announcement includes forward-looking statements under the Private Securities Litigation Reform Act. Such statements express Prime Medicine's expectations regarding clinical trial results, potential therapeutic impacts of PM359, and broader strategic goals. These statements are subject to numerous risks and uncertainties that could cause actual results to differ materially.