Ziopharm Oncology Inc. on Thursday said it is publicly offering $35 million in common stock.

The company said it is offering 7 million shares at $5 apiece, marking a 10 percent discount to the stock's closing price of $5.58 on Wednesday.

Shares fell 65 cents, or 12 percent, to $4.93 in morning trading.

The company expects net proceeds of about $32.8 million. It plans on using he proceeds to for drug development and general corporate purposes. The offering is expected to close June 2.

Jefferies & Co. is the sole bookrunning manager. The company granted underwriters a 30-day option to buy just over 1 million additional shares to cover overallotments.

Ziopharm has about 41.8 million shares of common stock outstanding.