FDA reviewers note inconsistencies, Impavido resistance

FDA reviewers raised concerns about trial inconsistencies and resistance to Impavido miltefosine from Paladin Labs Inc. (TSX:PLB), which is under Priority Review to treat leishmaniasis. Impavido met the primary endpoints in the Phase III trials that Paladin conducted in all three of the different forms -- visceral, cutaneous and mucosal --- of leishmaniasis for which the biotech is seeking approval of Impavido. However, FDA reviewers noted inconsistencies at different trial sites in the follow-up after six months of patients with residual signs and symptoms of visceral leishmaniasis. FDA's reanalysis of data in the subgroup of patients with residual signs and symptom favored the active-control amphotericin arm over Impavido on the primary endpoint of final cure (94.9% vs. 90.3%). The reviewers also said the higher relapse rate in the Impavido arm of the visceral leishmaniasis trial could be associated with resistance.

The comments came in Aeterna Zentaris Inc. (TSX:AEZ; NASDAQ:AEZS) in 2008. The product is approved for leishmaniasis in Europe, India and Central and South America. ...