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Supernus Pharma stock tumbles on sale of 6M shares

ROCKVILLE, Md. (AP) -- Shares of Supernus Pharmaceuticals Inc. tumbled Friday after the drug developer priced a sale of 6 million shares at $8 apiece.

That's a 19 percent discount to the company's closing price of $9.83 on Thursday.

The Rockville, Md., company had 24.5 million shares outstanding. Issuing stock can lower the value of current shareholders' stakes.

Supernus, which went public in May at $5 per share, does not yet have any products on the market. The company plans to start selling two epilepsy drugs, Oxtellar XR and Trokendi XR, next year.

The company is giving the underwriters a 30-day option to buy up to an additional 900,000 shares to cover any excess demand.

Supernus said in a regulatory filing that if the underwriters fully exercise their overallotment option, it anticipates proceeds of approximately $51.5 million after expenses.

The company plans to use the offering's proceeds to fund the expected commercial launches of Oxtellar XR and Trokendi XR; to fund the ongoing clinical development of some other drugs; to repay part of the principal of the term loans under its secured credit facility and for other general corporate purposes.

The stock dropped $1.70, or 17.3 percent, to $8.13 in morning trading. Shares have ranged from $4.30 to $16.68 since the initial public offering of stock.