What happened

Shares of Concert Pharmaceuticals (NASDAQ:CNCE) were cratering 28.9% as of 3:26 p.m. EST on Monday. The steep decline came after the company announced that experimental drug CTP-692 had failed to meet the primary and secondary endpoints in a phase 2 study as an adjunctive treatment for schizophrenia.

So what

It's always bad news for a clinical-stage biotech stock when a candidate fails in clinical testing. What's even worse for Concert is that CTP-692 was one of only two candidates in its pipeline. 

Man wearing a suit looking at a red line crashing through the floor

Image source: Getty Images.

Note the use of the past tense in that last statement. Concert is completely throwing in the towel on its CTP-692 program after the dismal phase 2 results. The company stated that the drug, a deuterated form (where hydrogen is replaced with deuterium) of the D-serine amino acid, didn't show a statistically significant improvement over placebo at any dose level for any of the endpoints of the study.

Concert Pharmaceuticals CEO Roger Tung said, "The body of evidence in the field supporting D-serine as an adjunctive treatment for schizophrenia was compelling and led us to advance CTP-692 into a Phase 2 proof of concept study. Unfortunately, we didn't see the results we hoped for to support continuation of this program." 

Now what

What's next for Concert? All of its chips now ride on CTP-543. The experimental drug is currently being evaluated in late-stage testing for the treatment of alopecia areata, an autoimmune disorder that results in hair loss. However, the drugmaker is also evaluating other potential candidates that could advance into clinical testing.

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