Prana discontinues PBT1 development
This article was originally published in Pharmaceutical Approvals Monthly
Executive Summary
Further development of Prana's investigational Alzheimer's agent clioquinol (PBT1) is "not warranted," the Australian firm says April 11. The firm has decided not to begin the "potentially pivotal" Phase II/III PLACQUE trial after finding that "unacceptably high levels of a di-iodo (toxic) form of PBT1" occur in the synthetic process of the drug. While Prana "has considered methods to reduce the levels of di-iodo impurity, it has come to the conclusion that attempts to reduce the impurity to safe levels are not likely to be successful in a timely manner." A "strategic review" of Prana's R&D programs is underway; a follow-on compound to PBT1 - PBT2 - is in Phase I...