GentiBio Announces First Participant Dosed in POLARIS Phase 1 Clinical Trial of GNTI-122 in Recently Diagnosed Type 1 Diabetes

Milestone marks first clinical evaluation of a targeted cell therapy designed to preserve natural insulin production

POLARIS trial enrolling at 10 specialized clinic sites across the U.S.

GentiBio on track to present key data in latter part of 2026 and 1H 2027 

CAMBRIDGE, Mass., March 18, 2026 /PRNewswire/ -- GentiBio, Inc., a clinical-stage biotechnology company pioneering engineered, antigen-specific regulatory T cell (EngTreg) therapies, today announced that the first participant has been dosed in POLARIS, a Phase 1 clinical trial evaluating GNTI-122, a novel single dose, autologous EngTreg investigational therapy for adults recently diagnosed with type 1 diabetes (T1D). GNTI-122 is designed to reduce or eliminate the need for life-long insulin injections in patients recently diagnosed with T1D.

"Dosing the first participant in the POLARIS trial is an important milestone for GentiBio and for the field of engineered immune tolerance," said Mark Bach, Chief Medical Officer at GentiBio. "We are studying GNTI-122 in people recently diagnosed with type 1 diabetes, which gives us the opportunity, starting with the very first participant, to look for biological signals that targeted immune regulation may help preserve the body's natural insulin production. We believe this approach can be transformative—and potentially curative—for people living with type 1 diabetes."

The Phase 1 study is designed to evaluate the safety, tolerability, and key efficacy biomarkers of GNTI-122 in adults within 120 days of T1D diagnosis. The trial is enrolling at 10 specialized clinical sites with expertise in cell-based immunotherapies across the U.S., with the first patient dosed at the University of North Carolina, Chapel Hill.

"Type 1 diabetes immediately affects daily life once it begins. Stopping the disease at its onset and preserving the pancreas' ability to make insulin would be a transformative step forward in improving outcomes and quality of life in people living with type 1 diabetes," said John Buse, MD, PhD, and Klara Klein, MD, PhD, both trial investigators at the University of North Carolina, Chapel Hill. "GNTI-122 offers a totally new approach to protect the insulin-producing cells of the pancreas. We're excited to be part of the program."

GNTI-122 is uniquely engineered to overcome the local inflammatory disease environment of T1D, where the body's natural Tregs have failed. GentiBio's platform generates high levels of stable, durable, and functional EngTregs that specifically target the pancreas to halt the autoimmune attack and provide the opportunity for long-lasting insulin independence.

GentiBio plans to present findings from the POLARIS study in the latter part of 2026 and the first half of 2027.

About GNTI-122 and EngTreg Therapy
GNTI-122 is a novel, single-treatment, autologous engineered regulatory T cell (EngTreg) investigational therapy designed to restore immune tolerance by selectively suppressing autoreactive immune responses that drive type 1 diabetes. GNTI-122 cells are designed to migrate to the pancreas and remain there to stably mitigate the immune response, preserving endogenous insulin production. GentiBio's EngTreg platform builds on foundational discoveries in Treg biology, recognized by the 2025 Nobel Prize in Physiology or Medicine, and is designed to deliver targeted, durable immunomodulation with the goal of addressing the root cause of autoimmune disease.

About the POLARIS Study
Phase 1, Single Dose, Open-LAbel Study of GNTI-122 in Adults with Recently dIagnoSed Type 1 Diabetes (T1D) [POLARIS (NCT06919354)] is a clinical trial enrolling adults aged 18–45 years within 120 days of T1D diagnosis. The study evaluates the safety and tolerability of escalating doses of GNTI-122 and includes secondary and exploratory assessments of pharmacodynamic activity and clinical biomarkers, including measures of beta cell function. Participants are followed for up to 78 weeks. For more information, visit polarisstudy.com or ClinicalTrials.gov.

About GentiBio
GentiBio is a biotechnology company developing engineered regulatory T cell (EngTreg) therapies to restore immune tolerance and transform the treatment of autoimmune and inflammatory diseases. GentiBio's EngTregs harness the underlying power of Tregs and are engineered for precision, durability, and scalable manufacture. GentiBio seeks to deliver disease modifying—and potentially curative—therapies for patients with significant unmet need. Learn more at www.gentibio.com.

Media Contact:
Peg Rusconi
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SOURCE GentiBio, Inc.