Regulus Therapeutics Inc. expects to raise US $42.8 million from its public offering of 4.5 million shares of its common stock priced at US $9.50 per unit.

The biopharmaceutical company is also making a separate 30-day option offer to underwriters to purchase an additional 675,000 in shares to settle overallotments.  The offers will close on July 22, 2013.

The core business of Regulus is distributing medicines against microRNA. It is presently on the development stage to find treatment for hepatitis C virus. Over the years, it has partnered with GlaxoSmithKline, AstraZeneca and Biogen Idec to develop microRNA therapeutics.

According to the company statement, Needham & Company and Wedbush PacGrow Life Science will act as co-managers for the public offering. On the other hand, Lazard Capital Markets, BMO Capital Markets Corp. and Cowen and Company will act as joint-book runners.

The Securities and Exchange Commission gave the go signal for Regulus to proceed with the offering on July 16, 2013.