Valeant to research psoriasis treatment

NEW YORK — Canadian drugmaker Valeant will work with British competitor AstraZeneca on a potential treatment for psoriasis a few months after biotech giant Amgen said it would end research on the drug because of a link to suicidal thoughts and behavior.

Valeant could pay AstraZeneca as much as $445 million if the drug is successfully developed and approved and meets sales targets. The companies will also share profit from the drug.

The companies said they plan to file for marketing approval of the drug brodalumab in the United States and the European Union during the fourth quarter. They want to market it as a treatment for moderate to severe psoriasis.

Amgen originally developed brodalumab and was studying it with AstraZeneca.

Amgen said in May that it decided to end work on brodalumab because some patients who took it experienced suicidal thoughts or behavior, which would have led to restrictions on its use. Amgen said it wanted to focus on other drugs.

The biggest-selling treatments for psoriasis are AbbVie’s Humira and Amgen’s Enbrel, both given by injection.

Amgen announced its decision in May, but AstraZeneca said the contract was terminated at the end of August.

If antitrust authorities approve the partnership, Valeant will be able to develop and sell brodalumab in most countries. Kyowa Hakko Kirin Co. owns the rights to the drug in Japan and some other countries in Asia.

U.S. shares of Valeant Pharmaceuticals International fell $6.55, or 2.9 percent, to $223.93 as markets slumped. AstraZeneca shares lost 59 cents to $30.69.

AstraZeneca and Amgen of Thousand Oaks (Ventura County) have been working together on antibody drugs since 2012, and that partnership is continuing.