CHICAGO — October 7, 2026
MAIA Biotechnology announced patient enrollment milestones across its ongoing Phase 2 THIO-101 and pivotal Phase 3 THIO-104 clinical trials evaluating ateganosine in non-small cell lung cancer (NSCLC). A total of 150 patients have now been treated with ateganosine sequenced with an immune checkpoint inhibitor (CPI) across the two studies. Enrollment has been completed in Part C of THIO-101, which evaluates ateganosine followed by the CPI cemiplimab. MAIA said the milestone advances its clinical development program targeting patients with NSCLC whose disease has progressed following prior chemotherapy and checkpoint inhibitor treatment.
THIO-101 Reaches Key Phase 2 Enrollment Milestone
The THIO-101 Phase 2 trial is a multicenter, open-label, dose-finding study evaluating ateganosine followed by cemiplimab in patients with advanced NSCLC who previously failed or developed resistance to checkpoint inhibitor-based treatment. MAIA recently reported an interim 90.5% disease control rate in the efficacy-evaluable population that had undergone at least one tumor scan after treatment initiation. Part C enrollment is now complete, moving the company toward completion of what MAIA describes as the first completed clinical study evaluating a telomere-targeting agent in cancer. The study is assessing safety, tolerability and antitumor activity, with overall response rate serving as a key efficacy endpoint.
Phase 3 THIO-104 Reaches 65% Enrollment Target
MAIA’s pivotal THIO-104 Phase 3 trial has enrolled 65 patients toward a target of 100 patients enrolled and dosed by the end of 2026, representing 65% of the company’s annual enrollment goal. The randomized, open-label study is evaluating ateganosine followed by PD-(L)1 inhibition in patients with third-line NSCLC whose disease has progressed after prior checkpoint inhibitor and/or chemotherapy treatment. The trial compares ateganosine with investigator’s choice of chemotherapy, with median overall survival serving as the primary efficacy endpoint. MAIA expects to conduct an interim analysis in 2027 as enrollment and dosing continue.
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Ateganosine Advances Under FDA Fast Track Designation
Ateganosine, also known as THIO or 6-thio-2’-deoxyguanosine, is an investigational telomere-targeting agent designed to exploit the dependence of cancer cells on telomerase and telomere maintenance. The modified nucleotide can induce telomeric DNA damage and activate immune responses, with the company developing a sequential strategy in which ateganosine is administered before a checkpoint inhibitor. The FDA granted Fast Track designation to ateganosine for NSCLC in July 2025, providing opportunities for more frequent regulatory interaction and potential eligibility for rolling review, Accelerated Approval and Priority Review. The ongoing Phase 3 program is intended to determine whether the approach can demonstrate clinical benefit in heavily pretreated third-line NSCLC patients.
Source::MAIA Biotechnology, press release
