NEW YORK (AP) - An investment firm that was burned by its big stake in troubled Valeant Pharmaceuticals said its CEO is retiring.

NEW YORK (AP) An investment firm that was burned by its big stake in troubled Valeant Pharmaceuticals said its CEO is retiring.

Ruane, Cunniff & Goldfarb said in a letter that Robert Goldfarb would retire and be replaced by David Poppe. The change comes after a mutual fund that Ruane, Cunniff & Goldfarb manages, called Sequoia Fund, fell 24 percent in the last year as Valeant's stock plummeted.

Ruane, Cunniff & Goldfarb has a 10.4 percent stake in Valeant, making it its biggest investor.

Valeant has struggled after ending ties with drug distribution company Philidor amid allegations that it steered pharmacy benefit managers toward Valeant's more expensive drugs over cheaper ones. Valeant said this week it would replace its CEO.

Valeant Pharmaceuticals International Inc.'s stock is down 84 percent in the last year.