Teva Pharmaceutical Industries Ltd (TEVA) - Get Report stock tumbled as much as 2% Thursday morning before erasing losses midday after Credit Suisse analyst Vamil Divan joined the bears and downgraded the Israeli generic drug maker to "underperform" from "neutral."

"We do not expect the core challenges they are facing to fade anytime soon," Divan wrote in a note. Pricing pressure and competition with other U.S. drug makers remain hurdles, and Teva's failure to elect a permanent CEO has hindered its ability to overcome those issues. Additionally, the threat of a generic version of Teva's multiple sclerosis drug Copaxone 40mg looms.

Reports that Teva is selling non-core assets are "encouraging," Credit Suisse noted, but Teva doesn't deserve credit until the final details of any sales are ironed out. Other upside risk revolves around the appointment of a credible CEO, Divan said.

Divan cut his price target for Teva stock 48% to $13 from $25. That implies a 21.2% downside from Teva's Wednesday close price of $16.49. After slashing dividends and guidance and losing its title of Israel's biggest company by market cap, Teva stock has crumbled 50% in one month. Shares traded down 0.85% to $16.35 Thursday.

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