Onyx Pharmaceuticals Inc. and Esperion Therapeutics Inc. both reported plans to sell 4 million common shares through public offerings that could raise the companies about $61 million and $80 million, respectively.

Richmond, Calif.-based Onyx said it would make the offer public pursuant to an effective registration statement filed last month with the SEC to sell up to $75 million in common stock. The company, which is selling all the stock, also said it would grant its underwriters an option to purchase up to an additional 600,000 common shares.

Based on Friday's $15.21 closing bid price of the stock, the offering could garner up to about $70 million if the option is exercised. Onyx's stock (NASDAQ:ONXX) lost 57 cents Monday to close at $14.64.

The company, which had 23.8 million shares outstanding prior to any sale, reported $37.7 million in cash, cash equivalents and marketable securities through March 31. Last month, Onyx cut staff to focus on its lead product, the cancer compound BAY 43-9006, which is in Phase II studies. (See BioWorld Today, June 13, 2003.)

Three New York-based firms are acting as the offering's underwriters - Morgan Stanley & Co. Inc., Lehman Brothers Inc. and SG Cowen Securities Corp. - with Morgan Stanley its sole bookrunner.

Esperion filed a registration statement with the SEC related to a potential public offering, with all shares to be offered by the Ann Arbor, Mich.-based company. It also said it plans to extend the underwriters an overallotment option to purchase up to an additional 600,000 shares.

Based on a $20.08 closing bid price Friday, the sale could gross up to about $92.4 million if the option is exercised. Esperion's stock (NASDAQ:ESPR) lost 19 cents Monday to close at $19.89.

The company, which had 29.5 million shares outstanding prior to any sale, reported about $38 million in cash and short-term investments through March 31. Esperion is developing therapies for cardiovascular and metabolic diseases related to HDL (high-density lipoprotein) cholesterol.

Lehman Brothers will act as bookrunner, while New York-based co-managers include Citigroup Global Markets Inc., Needham & Co. Inc. and U.S. Bancorp Piper Jaffray.