Incyte Corporation announced on April 3rd that it has discontinued the development of dexelvucitabine (DFC), an experimental nucleoside reverse transcriptase inhibitor (NRTI). This decision was based on several cases of increased amylase levels (hyperlipasemia), a sign of pancreas inflammation.

DFC, formerly known as Reverset™, was being studied in Phase II clinical trials. The hyperlipasemia was documented in Study 901, the long-term extension of Incyte's first Phase IIb trial (Study 203).

Study 901 included patients taking 100 mg or 200 mg DFC, with or without Epivir® ( 3TC) or Emtriva® (emtrcitabine). Approximately 70% of patients in Study 901 were on regimens containing either Epivir or Emtriva. After the results of Study 203 demonstrated that the effectivness of DFC was better in the absence of Epivir or Emtriva, some patients in Study 901 previously on Epivir or Emtriva were transitioned to regimens without Epivir or Emtriva. As this component of the patient safety database expanded, it became apparent that the frequency of severe hyperlipasemia in patients taking 200 mg DFC without Epivir or Emtriva was, in Incyte's view, unacceptably high.

Dr. Paul A. Friedman, president and CEO of Incyte, said that the observed rate of severe hyperlipasemia was 10% to 15% above the level that Incyte considered to be acceptable.

Incyte believed it was in the best interests of patients to discontinue development of DFC and, as a result, decided to stop enrollment of the recently initiated Phase IIb trial (Study 204). Incyte will be working with Study 901 researchers, along with the U.S. Food & Drug Administration, to determine the best approach for patients currently receiving DFC in Study 901 who may be obtaining benefit from DFC and have limited alternative treatment options at this time.

DFC was being co-developed with another company, Pharmasset. While Pharmasset does have the option of continuing the development of DFC, an Incyte spokesperson indicated that Pharmasset will also likely abondon development of this anti-HIV drug.

"This is an unfortunate and disappointing finding as we have seen clinically meaningful antiviral effects in patients taking the 200 mg dose of DFC without [Epivir] or [Emtriva]," Dr. Friedman said. "Even though lower doses could be safer, those we've studied have not been effective and we believe it is in the best interest of patients to discontinue DFC's development."

Source:

Incyte