PolTREG Doses First Patient in Phase II Trial for Pre-Symptomatic Type 1 Diabetes with PTG-007

PolTREG Doses First Patient in

Phase II Trial for Pre-Symptomatic Type 1 Diabetes with PTG-007

• PTG-007, an autologous cell therapy will be administered to 150 high-risk children aged 3–18, including a placebo-controlled arm.
• A parallel study presented to FDA and to be conducted by Immuthera has been received favorably, may include Polish patients in the U.S. Statistical analysis, and could be treated as pivotal.
• The project has received an $11.3 million non-dilutive grant from the Polish Medical Research Agency.
• PolTREG is developing Multi-edited, Allogeneic CAR-Tregulatory cell therapies which can be used to treat patients diagnosed with T1D (Stage 3), which, in combination with PTG-007 in Stage 1 and Stage 2, will provide clinical solutions for patients across all Stages of T1D.

4 August 2025 – PolTREG S.A. (Warsaw Stock Exchange: PTG), a pioneer in cell therapies for autoimmune diseases, and its U.S. subsidiary Immuthera, announced that they have administered the first dose of PTG-007 to a patient in their Phase II clinical trial for pre-symptomatic type 1 diabetes. The trial, called “Pre-Treg” will enroll up to 150 genetically high-risk children and adolescents (aged 3–18) who have not yet developed clinical symptoms of the disease. If successful, PolTREG aims to develop and register the world’s first therapy to prevent the onset of type 1 diabetes symptoms.

The company has proposed a parallel study to Pre-Treg to the U.S. Food and Drug Administration (FDA) in a recent Pre-IND meeting. The FDA’s response was that the U.S. Trial could potentially be registrational. Further, patients enrolled in Poland at Stage 1 of the disease may, upon completion of enrollment, be included in the U.S. statistical analysis of the study.

“Long-term data from our clinical program of PTG-007 in symptomatic type 1 diabetes confirm both the safety and efficacy of the therapy. Modern medicine is increasingly focusing on interventions applied earlier or even before the first clinical symptoms appear. Our therapy fits perfectly into this paradigm. By administering it at the earliest stage of disease development, we anticipate highly promising outcomes—possibly even halting disease progression before clinical symptoms emerge. If the trial confirms the therapy’s efficacy, we have the opportunity to develop and register the world’s first drug to prevent the clinical onset of type 1 diabetes. We believe this therapy holds significant market and partnership potential” - said Prof. Piotr Trzonkowski, CEO and Co-Founder of PolTREG S.A.

The Phase II study will include 150 participants in a randomized, placebo-controlled design. Recruitment is ongoing at three academic centers in Poland, with six additional clinical hospitals set to begin enrollment shortly.

PolTREG has been awarded a non-dilutive grant of PLN 31.7 million (approx. $11.3 million) from the Polish Medical Research Agency to support the execution of this Phase II trial.

PreTreg is one of PolTREG’s flagship programs. In type 1 diabetes, the autoimmune destruction of insulin-producing pancreatic islets underscores the importance of early intervention. In the pre-symptomatic phase, a sufficient number of islets remain to maintain normal glucose regulation, and the autoimmune process is still limited and more readily controllable. Preventive therapy at this stage could halt the autoimmune attack, leaving patients genetically predisposed but clinically healthy for life. Upon successful completion of this trial and confirmation of safety and efficacy, PolTREG could establish the first approved drug to prevent symptomatic type 1 diabetes.

Type 1 diabetes progresses through three stages. Stages 1 and 2 is considered presymptomatic and occurs in young children, typically 3 years old or older. Because these patients are not yet sick, safety is the highest priority. PTG-007’s 12 year safety data makes it an ideal treatment for this age group and this stage of disease. Diagnosis of Type 1 Diabetes occurs in Stage 3 when symptoms occur which can lead to potentially life threatening complications such as diabetic ketoacidocis, heart and blood vessel disease, nerve damage, eye damage, kidney disease, and foot damage. These patients are typically older and require supplemental insulin. Due to the complications in Stage 3, more aggressive treatments are warranted. PolTREG and Immuthera are developing Tregulatory cell therapies that have clinically derived edits to improve function, modifications to make them “off-the-shelf” (allogeneic), and a Chimeric Antigen Receptor to improve targeting of the disease causing cells that drive the autoimmune response. Taken together, PolTREG and Immuthera have a pipeline of Tregulatory cell therapies that will cover the full spectrum of presymptomatic and symptomatic Type 1 Diabetes.

PolTREG is also expanding its U.S. presence. In mid-June, the company established its wholly owned U.S. subsidiary, Immuthera, registered as a Delaware C Corporation. In recent weeks, prominent experts in diabetes and neuroimmunology—Prof. Jay Skyler, Prof. Desmond Schatz, and Prof. Lawrence Steinman—joined the company’s Scientific Advisory Board. In late July, PolTREG received the formal outcome of its pre-IND meeting with the FDA and is now preparing its IND submission. The company has partnered with Noble Capital Markets, Inc. and Kinexum Services LLC to support its U.S. regulatory strategy, and is collaborating with Swiss-based Antion Biosciences to develop next-generation allogeneic Treg therapies.

About PolTREG:

PolTREG is a global leader in developing autoimmune therapies based on T-regulatory cells (Tregs). Its lead product, PTG-007, autologous Treg treatment for early-onset Type-1 Diabetes (T1D) is ready for Phase 2/3 clinical testing, for which the company is seeking a partnership. PolTREG has established a robust platform encompassing a wide range of cell therapy approaches, including polyclonal TREG, CAR-TREG, allogeneic TREG, antigen-specific TREG, and TCR-TREG therapies.

About Immuthera:

Immuthera is pioneering novel cell-based therapies for clinical development in the United States and Canada. Immuthera will be clinically developing assets initially developed by PolTREG under the US FDA regulatory framework. Immuthera will have full access to PolTREG’s Research and Development capabilities and asset pipeline along with the ability to explore novel modalities developed by US Institutions. Immuthera is currently seeking investment to pursue the manufacture and clinical development of these assets in the United States.

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