Eyeing untapped niche, EpicentRx makes case for cancer toxicity prevention drug

Physicians lack an FDA-approved way to limit oral mucositis in head and neck cancer patients. EpicentRx wants to change that—and has shared a closer look at the phase 2 data that persuaded it to take the program deeper into the clinic.

The chemoradiotherapy used to treat head and neck cancers causes severe oral mucositis, a side effect that affects eating, drinking and swallowing in most patients. EpicentRx has identified RRx-001 as a way to counter the toxicity, pointing to the molecule’s ability to activate the anti-oxidative transcription factor Nrf2 and inhibit inflammation via the NLRP3 inflammasome to make its case. 

EpicentRx shared a look at data from the phase 2 clinical trial in June. Now, the company has added flesh to the bones of the June data drop, shedding light on how the other RRx-001 regimens performed and providing a look at secondary endpoints. 

Writing in the International Journal of Radiation Oncology, Biology and Physics, researchers involved in the PREVLAR phase 2a clinical trial set out how 53 patients responded to three regimens of the drug candidate. The median duration of severe oral mucositis was 8.5 days in one of the RRx-001 arms compared to 24 days in the control. Durations in the other RRx-001 arms were 10 days and 17 days. 

RRx-001 outperformed placebo numerically on other measures, too. The median duration of severe oral mucositis was five days in the most effective RRx-001 arm compared to 18 days in the control, although the advantage of the other two regimens was again less clear-cut.

Hypothesis testing of the efficacy endpoints was performed “for exploratory purposes only.” The authors of the paper were open about the limitations of the clinical trial, noting that “the small patient cohorts and an open-label design … create significant limits on the interpretability of the results.” 

Based on the data, EpicentRx plans to run a larger, randomized phase 2 study to generate more data on the use of RRx-001 in the prevention of oral mucositis. RRx-001 has already advanced into phase 3 in another indication, with the company evaluating the effect on survival of combining the investigational candidate with chemotherapy in heavily pretreated small cell lung cancer patients.