Shares of BioCryst Pharmaceuticals dropped 71 percent Monday after the Durham drug developer said a clinical trial for its experimental drug failed to help ill patients.
BioCryst stock fell $4.37 to close Monday at $1.77 – its lowest value in two and a half years – after the company said avoralstat did not help prevent swelling attacks of hereditary angioedema, a rare genetic disorder. Avoralstat was developed as an oral soft-gel formulation to replace treatments that must be injected.
BioCryst said it is not totally giving up on avoralstat, and expects study results by mid-year of a solid solid dosage of the treatment.
The goal of the avoralstat trial was to reduce the frequency of swelling attacks. The company said the drug did reduce the duration of the attacks for patients taking 500 milligram doses, but not those receiving 300 milligram doses. The drug was also safe and tolerated by the patients.
“This dosage form of avoralstat is not a viable formulation to move forward," said CEO Jon Stonehouse in a statement. "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,” Stonehouse said.
The 69-employee company has commercially developed Rapivab, the first new flu medication in 15 years, and is also developing several antivirals, including treatments for Ebola and Marburg virus infections.