NEW YORK (TheStreet) -- Horizon Pharmaceuticals (HZNP - Get Report) plummeted Monday after the company said CVS Caremark (CVS - Get Report) and Express Scripts (ESRX - Get Report) would put Horizon's two best-selling drugs on their exclusion lists at the beginning of 2015.
The move to the exclusion list means patients would incur more of a cost for the drugs unless they switch to cheaper alternatives. CVS and Express Scripts are the largest and second-largest pharmacy benefit managers in the U.S.
The two drugs are Duexis, which treats arthritis pains for those with stomach issues, and Vimovo, which treats osteoporosis and rheumatoid arthritis. Horizon acquired the U.S. rights to Vimovo from AstraZeneca (AZN - Get Report) in November.
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