Optimer Pharmaceuticals, which is developing antibiotics to treat gastrointestinal diseases, priced an initial public offering of 7 million shares at $7, below its downwardly revised range of $8 to $9, on Thursday night. The original range on the deal was $12 to $14. However, the firm did price more shares than the 5.25 million originally expected. Piper Jaffray and Jefferies were joint book runners on the deal. The stock is expected to begin trading on the NASDAQ under the ticker OPTR on Friday.
