What happened

Shares of the clinical-stage biotech Aptinyx (NASDAQ:APTX) are up by an eye-catching 55% as of 9:55 a.m. Tuesday morning. The drugmaker's stock is ripping higher in response to a positive midstage trial for its post-traumatic stress disorder (PTSD) candidate known as NYX-783.

Before the opening bell, Aptinyx announced that NYX-783 exhibited statistically significant and clinically meaningful efficacy results in a midstage trial consisting of 153 patients with PTSD. Equally as important, the company also reported that the drug showed a favorable adverse event and tolerability profile in the study. 

A man standing in front of a pink background and wearing sunglasses throwing money into the air

Image source: Getty Images.

So what

PTSD affects over 8.5 million Americans. Yet there are no drugs currently on the market that treat the underlying cause of this serious disorder. Aptinyx is hoping to change this situation for the better with NYX-783. Specifically, this novel NMDA receptor modulator is designed to target the root cause of PTSD, not simply alleviate symptoms associated with this disorder.

So, in short, Aptinyx might have a major new drug on its hands -- perhaps one capable of generating blockbuster-level sales following approval (greater than $1 billion a year). That's a huge deal for a company with a market cap of only $263 million at the time of writing. 

Now what

Aptinyx plans on discussing a registrational trial for the drug with regulators soon. So, if things go according to plan, NYX-783 may be in a late-stage study as soon as mid-2021. This small-cap biotech, in turn, will more than likely take advantage of this spike in its share price to raise funds for this upcoming trial. Phase 3 trials, after all, are an expensive endeavor.