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July 15 (Reuters) - Valeant Pharmaceuticals InternationalInc's experimental drug to treat the skin disorderpsoriasis carries a potential risk of suicide that ischallenging to assess due to limited data, according to apreliminary review by the U.S. Food and Drug Administrationpublished on Friday.
The review comes two days ahead of a meeting of outsideexperts who will advise the FDA on whether the drug should beapproved. The agency is not obliged to follow the advice of itsadvisory panels but typically does so.
In clinical trials of the drug, brodalumab, there were sixsuicides across all programs: four in psoriasis studies, one ina rheumatoid arthritis study and one in a psoriatic arthritisstudy.
"We have uncertainty about whether the signal for completedsuicide is a risk related to brodalumab treatment," FDAreviewers said. "From the available data, we cannot concludewhether or not suicide is a drug-related risk."
If approved, brodalumab has the potential to be used in alarge number of patients in the United States and likelyprescribed by a doctor that may not be familiar with screeningfor and diagnosing suicidal thinking and behavior, the reviewerssaid.
There are several risk management options that could providesome assurance that doctors and patients understand the safe useconditions of taking the drug.
"However, no risk management strategy will completelyeliminate the risk" they said.
Brodalumab, was initially developed by AstraZeneca Plc and Amgen Inc. In May, 2015, Amgen withdrewfrom the partnership after trials revealed the potential suiciderisk.
AstraZeneca subsequently licensed global rights to the drugto Valeant, whose fortunes have plummeted over the past yearamid criticism of its high drug prices and suspect relationshipwith a specialty pharmacy.
AstraZeneca recently terminated Valeant's license to marketbrodalumab in Europe and signed an exclusive license insteadwith Denmark's LEO Pharma.
Before the trial results, AstraZeneca said brodalumab couldgenerate annual sales of up to $1.5 billion a year. David Maris,an analyst at Wells Fargo, recently projected it would, ifapproved, generate just $250 million by 2020.
"Given the drug's safety profile, we expect a challengingcommercial launch," he said in a research report.
Brodalumab is known as an interleukin-17 inhibitor. Otherdrugs in the same class include Novartis AG's Cosentyxand Eli Lilly & Co's Taltz.
The drug would also compete with Amgen's Enbrel and AbbVie's Humira. (Reporting by Toni Clarke in Washington; Editing by MargueritaChoy)
