Durham drug developer BioCryst Pharmaceuticals said Tuesday that it is withdrawing what had been touted as a promising treatment for Hepatitis C in response to concerns about the drug's "toxicity profile."
BioCryst released the news after the close of market trading and said it would hold a teleconference at 8:30 a.m. Wednesday to discuss the situation with analysts and investors.
The 22-year-old drug development company has never brought a product to market in this country but its treatments for gout and for influenza are in advanced stages of human testing.
The company was hoping to move the Hepatitis drug to human testing but halted the drug indefinitely after consultation with the U.S. Food and Drug Administration, the agency that regulates and approves medicines.
"BioCryst agrees with the FDA's cautious approach," the company said in a statement. "FDA has previously placed clinical holds on other nucleotides under development."
The Hepatitis C drug, called BCX5191, had only been tested on animals and in bench experiments, said investor relations director Robert Bennett.
Bennett said putting the drug on hold will delay development by several months as BioCryst conducts further animal experiments with BCX5191.
"BioCryst will then determine whether to continue development of BCX5191, based on the results of these studies," the release said.
BioCryst, which emplys 42 people in Durham, announced earlier this month that it is buying California drug developer Presidio Pharmaceuticals for $101 million to combine the two companies' development of drugs to treat Hepatitis C. It's not clear how the regulatory concerns about BCX5191 will affect the planned merger.
BioCryst's Hepatitis C treatement is designed as an oral drug, whereas current treatments are injections that have painful side effects.
Hepatitis C affects 170 million people worldwide, including 4 million in the United States. It is a contagious liver disease that can lead to life-threatening complications, such as cirrhosis, liver cancer or liver failure.