MAIA Biotechnology Announces Open Market Purchases of Company Stock by Long-Standing Board Member and CEO

 

Source:  MAIA Biotechnology, Inc. 9/15/2026

MAIA Biotechnology, Inc. (NYSE American: MAIA) (“MAIA”, the “Company”), a clinical-stage biopharmaceutical company focused on developing immunotherapies for cancer, today announced that Board member Ramiro Guerrero, JD, LL.M. has increased his ownership stake in the Company through open market purchases totaling approximately $252,284. A total of 185,078 shares of MAIA common stock were acquired by Mr. Guerrero between August 20, 2026, and September 10, 2026, at an average common stock price of $1.36. MAIA also announced that 73,000 shares of MAIA common stock were acquired by Founder and CEO Vlad Vitoc, M.D. on September 14, 2026, at an average common stock price of $1.37.

“Our increased investments reflect the confidence we share across our leadership team in MAIA’s science, clinical strategy and long-term commercial potential,” said Dr. Vitoc. “With a growing body of clinical evidence supporting the ateganosine program, we believe MAIA is entering an increasingly important period in its development.”

“As MAIA has stated previously, its ongoing pivotal Phase 3 trial offers a statistically high probability of technical success,” Mr. Guerrero added. “I continue to believe MAIA is well positioned to create a great deal of value for its shareholders over time.”

MAIA’s ongoing pivotal Phase 3 trial THIO-104 evaluates ateganosine sequenced with checkpoint inhibitor cemiplimab versus investigator’s choice in third-line non-small cell lung cancer (NSCLC). Statistical assessments of ateganosine suggest a high probability of technical success and potential early full commercial approval if Phase 3 interim data is consistent with Phase 2 THIO-101 trial results. MAIA recently announced positive initial efficacy data from the ongoing Phase 2 THIO-101 clinical trial expansion, Part C, with third-line studies showing a disease control rate (DCR) of 90.5%¹ in the efficacy evaluable population who had at least one tumor scan after starting treatment. 

As of September 14, 2026, MAIA’s directors and officers hold a 21.34% stake in the Company.

About Ateganosine

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.

About MAIA Biotechnology, Inc.

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.