MAIA Biotechnology Opens Enrollment for Phase 2 Expansion Trial of Novel Telomere-Targeting Agent at Winship Cancer Institute of Emory University

Georgia’s only National Cancer Institute (NCI)-designated Comprehensive Cancer Center; well recognized at the forefront of cancer innovation and discovery nationwide

CHICAGO, June 18, 2026 (GLOBE NEWSWIRE) --MAIA Biotechnology, Inc. (NYSE American: MAIA) (“MAIA”, the “Company”), a clinical-stage biopharmaceutical company focused on developing targeted immunotherapies for cancer, today announced that the third U.S. clinical site in its Phase 2 THIO-101 expansion trial, Winship Cancer Institute of Emory University (“Winship”), is activated and now enrolling patients. The trial studies MAIA’s lead investigational telomere-targeting agent, ateganosine, as a third-line (3L) treatment for non-small cell lung cancer (NSCLC).

Matthew Failor, Director of Clinical Operations for MAIA, commented, “Winship is Georgia's only National Cancer Institute (NCI)-designated Comprehensive Cancer Center and is recognized at the forefront of cancer innovation and discovery nationwide. Winship offers a renowned thoracic oncology clinical research program with a proven track record in clinical trial development and conduct. With its premier medical team and extensive body of research, this cancer center is well-suited for our U.S. Phase 2 trial of ateganosine.”

The principal investigator for the THIO-101 expansion trial at Winship is Ticiana Leal, M.D., a professor in the Department of Hematology and Medical Oncology at the Emory University School of Medicine. Dr. Leal’s clinical research focuses on trials involving chemotherapy and immunotherapy agents for lung cancer.

Dr. Leal commented, “At Winship, we serve the state of Georgia and surrounding states where innovation in lung cancer treatment is a broad, underserved need. In Georgia, lung cancer is the leading cause of cancer-related deaths, with over 7,300 new cases in 2025. MAIA’s novel ateganosine agent, if approved, could address a significant gap in clinical care for the advanced-stage NSCLC patient population where there are no FDA-approved options available for treatment.”

THIO-101 is an ongoing Phase 2, open-label trial evaluating ateganosine followed by cemiplimab for NSCLC patients resistant to checkpoint inhibitors and chemotherapy. Parts A and B of the trial have shown strong early efficacy, with some patients showing survival exceeding two years, and now MAIA continues to expand the trial in the U.S.

Ateganosine (THIO, 6-thio-dG or 6-thio-2’-deoxyguanosine) is a first-in-class investigational telomere-targeting agent currently in clinical development to evaluate its activity in non-small cell lung cancer (NSCLC). Telomeres, along with the enzyme telomerase, play a fundamental role in the survival of cancer cells and their resistance to current therapies. The modified nucleotide 6-thio-2’-deoxyguanosine induces telomerase-dependent telomeric DNA modification, DNA damage responses, and selective cancer cell death. Ateganosine-damaged telomeric fragments accumulate in cytosolic micronuclei and activates both innate (cGAS/STING) and adaptive (T-cell) immune responses. The sequential treatment of ateganosine followed by PD-(L)1 inhibitors resulted in profound and persistent tumor regression in advanced, in vivo cancer models by induction of cancer type–specific immune memory. Ateganosine is presently developed as a second or later line of treatment for NSCLC for patients that have progressed beyond the standard-of-care regimen of existing checkpoint inhibitors.

THIO-101 is a multicenter, open-label, dose finding Phase 2 clinical trial. It is the first trial designed to evaluate ateganosine’s anti-tumor activity when followed by PD-(L)1 inhibition. The trial is testing the hypothesis that low doses of ateganosine administered prior to cemiplimab (Libtayo®) will enhance and prolong immune response in patients with advanced NSCLC who previously did not respond or developed resistance and progressed after first-line treatment regimen containing another checkpoint inhibitor. The trial design has two primary objectives: (1) to evaluate the safety and tolerability of ateganosine administered as an anticancer compound and a priming immune activator (2) to assess the clinical efficacy of ateganosine using Overall Response Rate (ORR) as the primary clinical endpoint. The expansion of the study will assess overall response rates (ORR) in advanced NSCLC patients receiving third line (3L) therapy who were resistant to previous checkpoint inhibitor treatments (CPI) and chemotherapy. Treatment with ateganosine followed by cemiplimab (Libtayo®) has shown an acceptable safety profile to date in a heavily pre-treated population. For more information on this Phase II trial, please visit ClinicalTrials.gov using the identifier NCT05208944.

MAIA is a targeted therapy, immuno-oncology company focused on the development and commercialization of potential first-in-class drugs with novel mechanisms of action that are intended to meaningfully improve and extend the lives of people with cancer. Our lead program is ateganosine (THIO), a potential first-in-class cancer telomere targeting agent in clinical development for the treatment of NSCLC patients with telomerase-positive cancer cells. For more information, please visitwww.maiabiotech.com.

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