Cempra Pharmaceuticals expects the offering price for its planned IPO to be between $11 and $13, the Chapel Hill company reported in a regulatory filing last week.
The company, which filed to go public in October, had earlier said it hoped to raise nearly $90 million through the offering.
Cempra plans to sell 6 million shares, with underwriters of the offering having the option to buy up to 900,000 additional shares.
Cempra is developing treatments for drug-resistant skin infections and pneumonia. The company has two antibiotics in clinical trials.
One targets patients with pneumonia. The other is being tested as a treatment for skin infections, including methicillin-resistant Staphylococcus aureus, or MRSA.
The company's founder and CEO, Prabhavathi Fernandes, is a microbiologist who was involved in developing clarithromycin, a popular antibiotic used for sinus infections, bronchitis and pneumonia.
Cempra, which has 15 employees, has raised nearly $80 million since it was founded in 2006.
The company is one of several health care-related Triangle firms planning to go public.
Argos Therapeutics, a Durham company developing experimental medicines to treat kidney cancer, HIV, lupus and other diseases, filed plans in July to raise as much as $86.3 million in an initial public offering of stock.
LipoScience, a Raleigh company that sells a blood test to check patients' risk of heart disease, filed IPO plans in June.

Business reporter David Bracken came to the N&O in 2004. He covers commercial and residential real estate. Contact David at 919-829-4548 or