Shares in UK speciality pharmaceutical group Neuropharm plunged 82% yesterday after it emerged the future of its lead drug candidate looks uncertain.

Phase III results of the company’s autism drug NPL-2008 – a novel formulation of fluoxetine – showed that while it was safe and generally well-tolerated in patients, it missed the primary endpoint of reducing repetitive behaviour associated with the condition.

The SOFIA study found that repetitive behaviours were reduced in both patients receiving treatment with NPL-2008 and a placebo, but failed to demonstrate a statistically-significant difference between the two study arms.

“These initial results are both unexpected and disappointing, “ said the company’s chief executive, adding: “we await the results of the full analysis which is currently ongoing”.

US approval looking unlikely
Investor confidence in the group was heavily shaken because it was widely expected that results of the trial would form the basis of a regulatory submission in the US, which is now looking unlikely.

“In our view, the failure of a well-designed US Phase III trial makes it unlikely that NPL-2008 will receive US regulatory approval for autism, unless further analysis of the primary and secondary endpoints shows statistically significant differences,” analysts at Piper Jaffray said in a note, reports Reuters.