Biopharma firm Aptinyx has reported positive results from the first Phase II study of its new NMDA receptor modulator, NYX-783, in patients with post-traumatic stress disorder (PTSD).

During the Phase 2 trial, NYX-783 showed statistically clinically meaningful efficacy results, as well as a favourable adverse event and tolerability profile.

PTSD is characterised by intrusive symptoms, avoidance, negative alteration in cognition and mood, hyperarousal, and / or arousal alterations after the experience of trauma.

Trauma includes combat exposure, car accidents, sexual or other physical assault, abuse, natural disasters and others.

The multi-centre, placebo-controlled, double-blind, randomised, Sequential Parallel Comparison Design (SPCD) study was conducted on 153 patients with PTSD.

Conducted in two, four-week sequential stages, patients were randomly selected to receive either placebo or 10 mg or 50mn dose of NYX-783 in Stage one.

All patients on placebo in Stage one were re-randomised in the second stage to again receive placebo, or begin NYX-783 10 mg, or NYX-783 50 mg.

The trial’s primary endpoint was the change in CAPS-5 Total Score and symptom domain sub-scores (Arousal and Reactivity, Negative Cognitions and Mood, Intrusions, and Avoidance) for Stage one and two, combined as weighted effects.

Results showed the primary objective was achieved as both dose levels demonstrated clinically meaningful and statistically significant improvement on CAPS-5 Arousal and Reactivity Score.

Clinically meaningful improvement was observed in the CAPS-5 Total Score within four weeks in 50 mg dose arm.

Across endpoints in the trial, a clear dose response was observed with the 50mg dose, indicating a more consistent effect than the 10mg dose.

Aptinyx president and CEO Norbert Riedel said: “People suffering from PTSD have immense unmet medical needs and the few existing therapeutic options offer limited benefit.

“We believe these results indicate that the mechanism of NYX-783, which modulates NMDA receptors to enhance extinction learning, addresses the putative underlying pathology of PTSD.”

According to the results, the company now plans to begin a pivotal study next year.