Guggenheim analyst William Tanner calls Alkermes' trial failures for ALKS 5461 in major depressive disorder a "major setback in the evolution of the company." Success in developing '5461 would have provided evidence that Alkermes had "turned the corner" on its way to a more diversified revenue base beyond royalties, Tanner tells investors in a research note. He believes that while the company successfully developed Vivitrol, it is fair to view the dug as a "modest commercial success, at best." Tanner keeps a Neutral rating on shares of Alkermes. The stock is down 34%, or $20.56, to $39.86 in pre-market trading.