MAIA Biotechnology opens third US site for ateganosine Phase 2 trial
MAIA Biotechnology has activated Winship Cancer Institute of Emory University as the third US clinical site in its THIO-101 Phase 2 expansion trial, with patient enrolment now open. The trial is evaluating ateganosine, the company's lead investigational telomere-targeting agent, as a third-line treatment for patients with advanced non-small cell lung cancer who have progressed after checkpoint inhibitor and chemotherapy regimens.
Ticiana Leal, professor of haematology and medical oncology at Emory University School of Medicine, is serving as principal investigator at the Winship site. Dr Leal noted that lung cancer is the leading cause of cancer-related deaths in Georgia, with more than 7,300 new cases recorded in 2025, and said the region represents an underserved patient population with limited options at the third-line setting. Matthew Failor, MAIA's director of clinical operations, described Winship, Georgia's only NCI-designated Comprehensive Cancer Center, as well-suited to the trial given its established thoracic oncology research programme.
The drug and trial design
Ateganosine, also designated THIO or 6-thio-2'-deoxyguanosine, is a modified nucleotide that the company describes as a potential first-in-class telomere-targeting agent. It works by exploiting telomerase activity in cancer cells: the modified nucleotide is incorporated into telomeric DNA, triggering DNA damage responses and selective cancer cell death. MAIA says the resulting telomeric DNA fragments accumulate in cytosolic micronuclei and activate both innate immune signalling via the cGAS/STING pathway and adaptive T-cell responses.
THIO-101 is a multicenter, open-label, dose-finding study. It evaluates ateganosine administered sequentially before cemiplimab (Libtayo), a PD-1 inhibitor marketed by Regeneron and Sanofi. The trial carries two primary objectives: assessing the safety and tolerability of ateganosine as both an anti-tumour compound and an immune primer, and measuring overall response rate as the primary efficacy endpoint. MAIA reported that Parts A and B of the trial have produced encouraging early signals, with some patients showing survival extending beyond two years, though no formal interim data or response rate figures were disclosed in this announcement.
Market context and competitive landscape
Third-line NSCLC is a particularly difficult setting. Approved options thin out sharply after first- and second-line checkpoint inhibitor combinations, and patients who have progressed on both chemotherapy and a PD-(L)1 inhibitor have very limited standard-of-care choices. This unmet need has drawn a number of clinical-stage companies pursuing diverse mechanisms, including antibody-drug conjugates, bispecific antibodies, and novel immune-priming approaches.
Telomere targeting as a therapeutic strategy remains relatively rare in the clinical-stage NSCLC landscape, which gives ateganosine a degree of mechanistic differentiation. However, the pathway from Phase 2 open-label data to regulatory approval in a heavily pre-treated population is demanding. Regulators typically require randomised evidence to confirm survival benefit, and an overall response rate read-out, while useful as a signal of activity, will need to be supported by durability data and a defined regulatory pathway before the programme can attract meaningful partnership interest.
MAIA has not disclosed the total number of patients enrolled to date across all THIO-101 sites, the timeline to primary data readout, or any partnership arrangements. The company is listed on NYSE American, suggesting a small-cap profile with limited internal capital. Investors will be watching for a data disclosure event and any indication of FDA feedback on a potential registration path as the next material milestones for this programme.