BioCryst Pharmaceuticals Is Plummeting 65%

Shares of BioCryst Pharmaceuticals, Inc. BCRX were trading lower by more than 65 percent early Monday morning after the company reported disappointing results from a clinical trial.

BioCryst designs, optimizes and develops novel small molecule drugs that block key enzymes involved in rare diseases. The company's ongoing study, OPuS-2 was a a clinical trial of avoralstat administered three times daily as a liquid-filled soft gel formulation for the prophylactic treatment of hereditary angioedema (HAE) attacks.

In the study, 38 subjects received avoralstat 500 mg, 36 subjects received avoralstat 300 mg, and 36 subjects received a placebo. The company announced that treatment with the 500 and 300 mg of avoralstat failed to demonstrate a statistically significantly lower mean attack rate versus the placebo.

"OPuS-2 was a well-designed and executed trial that gave us a clear answer; this dosage form of avoralstat is not a viable formulation to move forward," said Jon P. Stonehouse, President & Chief Executive Officer. "While we are disappointed in the study results, we learned that meaningfully better exposure is needed for avoralstat to succeed. We expect results from a relative bioavailability study testing a novel solid dosage form of avoralstat by mid-year - the primary goals of this study are to achieve much higher exposures and twice daily dosing. Our other opportunity to achieve higher exposure of an oral kallikrein inhibitor is with BCX7353 - we expect results from the BCX7353 APeX-1 dose ranging study in HAE patients by year end."

A conference call is scheduled for Monday at 8:00 a.m. ET to discuss the results of the trial. The webcast can be accessed through the company's investor relations website.