Merrimack Pharmaceuticals (MACK 0.34%) is gearing up for a double dose of fund-raising. The company announced that it will concurrently float both a common stock and a convertible notes issue in a public offering. In the former, Merrimack will offer $50 million worth of shares, while the latter will take the form of $75 million in senior notes maturing in 2020. Additionally, the company expects that it will grant its underwriters a 30-day purchase option for up to an additional $7.5 million worth of common shares and $11.25 million of the convertible notes.

The exact per-unit price of both securities will be hashed out between Merrimack and the underwriters.

The company said it plans to use the proceeds of the issues to fund commercial efforts for its goods, as well as product development, research, and "general corporate purposes."

JPMorgan Chase unit J.P. Morgan Securities and Bank of America's Merrill Lynch are the joint book-running managers of the issue.  

At the moment, Merrimack has just over 96 million shares outstanding, and its most recent closing stock price was $6.99 per share.