MAIA Biotechnology Updates Phase 2 Trial of New Cancer Treatment

MAIA Biotechnology, Inc., a clinical-stage biopharmaceutical enterprise, has announced encouraging treatment results from its Phase 2 clinical trial, THIO-101. This study is investigating the efficacy of THIO when sequenced with the immune checkpoint inhibitor cemiplimab (Libtayo®) in patients suffering from advanced non-small cell lung cancer (NSCLC) who have not responded to two or more conventional treatments.

The therapeutic regimen in the trial is structured on a three-week cycle. Patients receive THIO in 60mg doses over the first three days, followed by a day of immune activation without dosing, and cemiplimab 350mg on the fifth day. As of the most recent data cutoff on June 12, 2024, six patients have continued treatment for over twelve months. The combination of THIO and cemiplimab has shown to be well tolerated, exhibiting significantly lower toxicity compared to standard treatments. The extended treatment duration highlights the safety and effectiveness of MAIA's innovative NSCLC therapy.

Dr. Vlad Vitoc, Chairman and CEO of MAIA, expressed optimism, noting that the longest-treated patient has completed 21 cycles of THIO and cemiplimab. Six patients have surpassed the twelve-month survival mark and are still undergoing treatment. Vitoc emphasized that current second-line therapies typically last about 3-4 months, with third-line treatments being even shorter. The longer duration of treatment observed with THIO is promising, indicating its potential as a durable and effective option for advanced NSCLC patients with limited alternatives.

THIO, also known as 6-thio-2’-deoxyguanosine, is a pioneering telomere-targeting agent in clinical development for NSCLC. Telomeres and the enzyme telomerase are crucial for cancer cell survival and resistance to existing treatments. THIO induces telomerase-dependent modifications in telomeric DNA, triggers DNA damage responses, and selectively kills cancer cells. The damaged telomeric fragments accumulate in cytosolic micronuclei, activating both innate and adaptive immune responses. Sequential treatment with THIO followed by PD-(L)1 inhibitors has led to significant and lasting tumor regression in advanced cancer models, inducing cancer-specific immune memory.

The THIO-101 trial is a multicenter, open-label, dose-finding Phase 2 study. It is the first trial to evaluate the anti-tumor activity of THIO followed by PD-(L)1 inhibition. This trial hypothesizes that low doses of THIO prior to cemiplimab will enhance and prolong immune responses in advanced NSCLC patients who have not responded or have progressed after initial checkpoint inhibitor treatments. The primary objectives are to assess the safety and tolerability of THIO as an anticancer agent and priming immune activator, and to evaluate its clinical efficacy using Overall Response Rate (ORR) as the primary endpoint. So far, the treatment with cemiplimab followed by THIO has been generally well tolerated in a heavily pre-treated population.

MAIA Biotechnology, Inc. is committed to developing and commercializing innovative therapies designed to significantly improve the lives of cancer patients. Its lead program, THIO, is currently in clinical development as a potential treatment for NSCLC patients with telomerase-positive cancer cells.