MAIA Biotechnology has selected the dose in its Phase II THIO-101 clinical trial of THIO (6-thio-dG or 6-thio-2’-deoxyguanosine) to treat advanced non-small cell lung cancer (NSCLC) patients.

The selected dose of 180mg THIO per cycle is claimed to have shown a better safety profile and efficacy in trials in NSCLC patients.

The open-label, multicentre, dose-finding trial is designed to analyse the anti-tumour activity of THIO plus Regeneron's cemiplimab (Libtayo).

It will analyse whether low doses of THIO administered before cemiplimab can increase and lengthen the immune response in trial subjects.

The dose-finding portion of the trial analysed 60mg, 180mg, and 360mg doses of THIO per cycle, followed by 350mg cemiplimab.

In this section, 180mg/cycle was demonstrated to outperform the other doses in the crucial efficacy measures for NSCLC studies. 

With the latest development, all trial participants to be enrolled in the trial will receive a 180mg/cycle dose of THIO.

An investigational, telomere-targeting agent, THIO is in development as a second or later line NSCLC treatment in people who have advanced beyond standard-of-care treatment with checkpoint inhibitors.

MAIA chairman and CEO Vlad Vitoc said: “All THIO dose levels tested exceeded the disease control rate (DCR) thresholds in stage one of the THIO-101 Phase II trial. 

“Among the three studied doses, the 180mg dose showed stronger DCR and preliminary response rates, compared to other doses.

“These results are particularly impressive in this pool of patients who were heavily pre-treated and resistant to prior treatments with immune checkpoint inhibitors, a group that does not yet have standard of care treatment.”

The company intends to seek accelerated approval for THIO to treat advanced NSCLC patients in the US.

In October this year, MAIA reported positive initial efficacy results from its THIO-101 trial of THIO in patients with NSCLC in sequential combination with cemiplimab.