Exhibit 99.1

MAIA Biotechnology Announces Share Repurchase Program

CHICAGO, IL – September 28, 2023 – MAIA Biotechnology, Inc. (NYSE American: MAIA), a clinical stage company developing telomere-targeting immunotherapies for cancer, today announced that its Board of Directors has approved a share repurchase program with authorization to purchase up to $800,000 of its Class A common stock through September 2024.

“This share repurchase program demonstrates the confidence we have in our market opportunity and our strategy to invest for long-term growth, which we believe is not reflected in the current market valuation,” said Vlad Vitoc, MAIA’s Chief Executive Officer. “By establishing a repurchase plan, we add another tool to our arsenal that can assist with our future financing efforts, enable us to unlock more of the long-term opportunity we see ahead, and drive sustainable value for all stakeholders.”

With a share repurchase program, MAIA may repurchase shares from time to time through various methods, including in open market transactions, in privately negotiated transactions or otherwise, including through the use of trading plans intended to qualify under Rule 10b5-1 under the Securities Exchange Act of 1934, as amended, in compliance with applicable state and federal securities laws. The timing, as well as the number and value of shares repurchased under the program, will be determined by the Company at its discretion and will depend on a variety of factors, including our assessment of the intrinsic value of the Company’s common stock, the market price of the Company’s common stock, general market and economic conditions, available liquidity, compliance with the Company’s debt and other agreements, applicable legal requirements, the nature of other investment opportunities available to the Company, and other considerations. The Company is not obligated to purchase any shares under the repurchase program, and the program may be suspended, modified, or discontinued at any time without prior notice. The Company expects to fund the repurchases by using cash on hand and expected free cash flow to be generated in the future.

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 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 visit www.maiabiotech.com.

Forward Looking Statements

MAIA cautions that all statements, other than statements of historical facts contained in this press release, are forward-looking statements. Forward-looking statements are subject to known and unknown risks, uncertainties, and other factors that may cause our or our industry’s actual results, levels or activity, performance or achievements to be materially different from those anticipated by such statements. The use of words such as “may,” “might,” “will,” “should,” “could,” “expect,” “plan,” “anticipate,” “believe,” “estimate,” “project,” “intend,” “future,” “potential,” or “continue,” and other similar expressions are intended to identify forward looking statements. However, the absence of these words does not mean that statements are not forward-looking. For example, all statements we make regarding (i) the initiation, timing, cost, progress and results of our preclinical and clinical studies and our research and development programs, (ii) our ability to advance product candidates into, and successfully complete, clinical studies, (iii) the timing or likelihood of regulatory filings and approvals, (iv) our ability to develop, manufacture and commercialize our product candidates and to improve the manufacturing process, (v) the rate and degree of market acceptance of our product candidates, (vi) the size and growth potential of the markets for our product candidates and our ability to serve those markets, and (vii) our expectations regarding our ability to obtain and maintain intellectual property protection for our product candidates, are forward looking. All forward-looking statements are based on current estimates, assumptions and expectations by our management that, although we believe to be reasonable, are inherently uncertain. Any forward-looking statement expressing an expectation or belief as to future events is expressed in good faith and believed to be reasonable at the time such forward-looking statement is made. However, these statements are not guarantees of future events and are subject to risks and uncertainties and other factors beyond our control that may cause actual results to differ materially from those expressed in any forward-looking statement. Any forward-looking statement speaks only as of the date on which it was made. We undertake no obligation to publicly update or revise any forward-looking statement, whether as

a result of new information, future events or otherwise, except as required by law. In this release, unless the context requires otherwise, “MAIA,” “Company,” “we,” “our,” and “us” refers to MAIA Biotechnology, Inc. and its subsidiaries.

Investor Inquiries

MAIA Biotechnology

Joseph McGuire

Chief Financial Officer

jmcguire@maiabiotech.com

904-228-2603

Investor Relations

ir@maiabiotech.com