MAIA Biotechnology's lead candidate, THIO, in conjunction with Regeneron's cemiplimab, has shown a significant increase in overall survival (OS) for patients with advanced non-small cell lung cancer (NSCLC) who have failed two or more standard-of-care therapies. The Phase 2 THIO-101 trial results indicate a median OS of 16.9 months, marking a potential breakthrough in a challenging treatment landscape.
THIO-101 Trial Results
The THIO-101 trial is a pivotal Phase 2 study evaluating THIO, a first-in-class telomere-targeting agent, sequenced with the immune checkpoint inhibitor cemiplimab in patients with advanced NSCLC. As of January 15, 2025, data from 22 patients in the third-line setting showed a median overall survival of 16.9 months. The analysis demonstrated a 95% confidence interval lower bound of 12.5 months and a 99% CI lower bound of 10.8 months. This is a notable improvement over standard-of-care chemotherapy, which typically yields an OS of 5 to 6 months in similar patient populations.
Vlad Vitoc, M.D., CEO of MAIA, stated, "Treatment with THIO now shows a 99% probability that overall survival will extend past chemotherapy's measure by a wide margin. THIO's efficacy in advanced stages of NSCLC continues to exceed our expectations, especially in third-line treatment where the cancer is typically even more resistant to therapy."
Mechanism of Action and Clinical Significance
THIO (6-thio-dG or 6-thio-2’-deoxyguanosine) is designed to induce telomeric DNA damage and enhance cancer-specific immune responses. By targeting telomeres, which play a crucial role in cancer cell survival and resistance, THIO aims to overcome the limitations of existing therapies. The sequential treatment with THIO followed by PD-(L)1 inhibitors has demonstrated profound and persistent tumor regression in advanced in vivo cancer models by induction of cancer type–specific immune memory.
The 38% overall response rate (ORR) and 5.5 months median progression-free survival (PFS) observed in the trial further underscore THIO's potential. These results are particularly significant given the limited treatment options available for patients who have progressed on prior checkpoint inhibitors and platinum-based chemotherapy.
Regulatory Strategy and Future Outlook
MAIA Biotechnology believes that the compelling data from the THIO-101 trial could support an accelerated FDA approval pathway. The company is continuing to expand the trial to further evaluate THIO's efficacy and safety profile. With a strong focus on responsible capital management and continued insider investment, MAIA is well-positioned to advance THIO towards commercialization and establish a new standard of care for advanced NSCLC.
Dr. Vitoc added, "With our latest overall survival results, our outlook for potential FDA commercial approval of THIO is stronger than ever."
