MAIA Biotechnology is set to present updated findings from its Phase 2 THIO-101 clinical trial at the Society for Immunotherapy of Cancer (SITC) 39th Annual Meeting, highlighting the potential of THIO-101 in treating advanced non-small cell lung cancer (NSCLC). The data suggests that THIO-101, when sequenced with Regeneron's cemiplimab (Libtayo®), offers long-term therapeutic benefits for patients who have failed two or more standard-of-care regimens.
The late-breaking abstract (LBA) presentation will feature new efficacy and safety data from the THIO-101 trial. A poster presentation will further detail the long-term benefits observed with THIO sequenced with cemiplimab, even beyond treatment cessation. These findings are particularly significant for advanced-stage patients resistant to CPI and chemotherapy treatments, who often have limited treatment options.
THIO-101: Targeting Telomeres for Immunotherapy Enhancement
THIO (6-thio-dG), MAIA's first-in-class investigational telomere-targeting agent, is designed to disrupt telomerase activity in cancer cells. Telomeres and telomerase are crucial for cancer cell survival and resistance to therapies. THIO induces telomerase-dependent telomeric DNA modification, leading to DNA damage responses and selective cancer cell death. This process activates both innate (cGAS/STING) and adaptive (T-cell) immune responses.
Preclinical models have shown that sequential treatment with THIO followed by PD-(L)1 inhibitors results in significant and lasting tumor regression by inducing cancer type-specific immune memory. THIO is being developed as a second or later line of treatment for NSCLC patients who have progressed after initial checkpoint inhibitor therapy.
Clinical Trial Details and Promising Interim Results
The THIO-101 trial (NCT05208944) is a multicenter, open-label, Phase 2 study evaluating THIO's anti-tumor activity when followed by PD-(L)1 inhibition. The trial aims to assess the safety, tolerability, and clinical efficacy of THIO, using Overall Response Rate (ORR) as the primary endpoint. The treatment regimen of THIO followed by cemiplimab has been generally well-tolerated in heavily pre-treated patients.
As of August 1, 2024, 16 patients in the THIO-101 trial had survival follow-up surpassing 12 months, including 9 in third-line treatment (3L). Interim median survival follow-up in 3L was 10.6 months, which compares favorably to the current standard-of-care overall survival of 5.8 months in this setting (Girard N, et al. J Thorac Onc 2009;12:1544-1549).
Vlad Vitoc, M.D., Chairman and CEO of MAIA, stated, "We believe that our latest data is compelling and further supports the ability of THIO to produce cancer cell specific immune memory and to remain active against cancer cells after extended periods of time... In our opinion, the combination of THIO with a CPI is showing promise as a durable and effective NSCLC treatment."
