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Chelsea Therapeutics skids as study fails

NEW YORK (AP) -- Share of Chelsea Therapeutics International Ltd. plunged Thursday after the company said it is ending studies of a potential treatment for rheumatoid arthritis.

The company announced the decision while reporting results from a midstage clinical trial of the drug, which is designated CH-4051. In the trial, CH-4051 did not work better than methotrexate, a standard treatment for rheumatoid arthritis. Chelsea Therapeutics said the patients who were treated with methotrexate did better than it expected.

The study compared CH-4501 to methotrexate in patients who were not helped by previous treatment with methotrexate.

The Charlotte, N.C., company said it plans to focus its resources on Northera, a drug designed to prevent falling in patients with conditions like Parkinson's disease. It asked the Food and Drug Administration to approve the drug in September. However the FDA asked for further studies of Northera in March, and earlier this month, the company said it may have to add more patients and change its goal in clinical studies of the drug.

Chelsea Therapeutics may request marketing approval again in the first quarter of 2013. The FDA could make a decision six to 10 months later.

Northera is designed to treat neurogenic orthostatic hypotension, which is a drop in blood pressure on standing. It's a common symptom of Parkinson's disease, and can make patients get dizzy and fall.

Chelsea Therapeutics International shares dropped 54 cents, or 27.7 percent, to $1.41 in morning trading. The stock is down 47 percent since March 29