Biopharmaceutical company Arena Pharmaceuticals, Inc. (ARNA) said Wednesday after the bell that Merck and Co. Inc. (MRK) has informed that company's decision to discontinue development of MK-1903, an atherosclerosis drug being developed under its research collaboration with Arena. Merck also informed Arena that the company will not continue the collaboration. Shares of Arena dropped more than 6% in after-hours trading. Merck made the decision to discontinue development of MK-1903 following evaluation of the results of a recently completed mid-stage, Phase 2a clinical trial. The randomized, double-blind, placebo-controlled trial evaluated the safety, tolerability and potential efficacy in patients with dyslipidemia.
According to Merck, elevation of HDL cholesterol or good cholesterol, compared to placebo did not meet the trial's pre-specified primary objective for efficacy. The company added that no safety concerns were implicated as drivers of the decision to discontinue development of the drug.
Atherosclerosis, which occurs when there is a build-up of dangerous plaque in the arteries, can lead to heart attacks.
Jack Lief, Arena's President and Chief Executive Officer, said, "We are disappointed that the trial results did not lead to further development of this program, but it has been a pleasure to work with Merck and we welcome the opportunity to collaborate again. We continue to focus on our other internal and partnered programs and the FDA approval of our lead drug candidate, lorcaserin for weight management."
ARNA closed Wednesday's regular trading session at $3.79, down $0.05 or 1.30% on a volume of 1.60 million shares. In after-hours trading, the stock further lost $0.23 or 6.07% to close at $3.56.
MRK closed Wednesday's trading at $37.25, down $0.50 or 1.32% on a volume of 12.75 million shares.
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