The U.S. FDA has accepted Cempra’s new drug application (NDA) for two different formulations of Solithera (solithromycin) to treat community-acquired bacterial pneumonia (CABP), the company announced. This means the FDA can now review the application for both the tablet and an intravenously injected form of the drug.

“The FDA’s acceptance of our two NDA filings brings us one step closer to the potential approval by the end of 2016 and U.S. commercial launch of Solithera,” Cempra President and CEO Dr. Prabhavathi Fernandes said in a press release. “If approved, Solithera would be a significant milestone in the treatment of CABP, as bacterial resistance to older treatments has continued to rise.”

The safety and efficacy of Solithera for the treatment of CABP has been tested in two Phase 3 clinical trials, one assessing the capsule form of the drug candidate and the other in the intravenous form. The oral formula has been found to be as effective and safe as moxifloxacin, a commonly used antibacterial agent.

Solithera is a powerful macrolide, a naturally occurring antibiotic that binds to the bacteria’s molecular machine called ribosome, inhibiting protein synthesis. Unlike other macrolides, which bind to only one site on the bacteria’s ribosome, Solithera has the ability to bind to three sites. This is thought to limit the development of bacterial resistance and makes Solithera effective against most macrolide-resistant bacterial strains.

Previous research has shown that Solithera is effective against Streptococcus pneumonia and other species of Streptococcus as well as community-acquired methicillin resistant Staphylococcus aureus (MRSA), Haemophilus causing an infection colloquially known as bacterial influenza, and bird flu-causing Mycobacterium avium.

CABP is one of the most commonly diagnosed infections in the U.S., with 5 to 10 million people being diagnosed each year. CABP is the main cause of infection-caused death, especially in elderly people and babies.

Macrolides are the most commonly prescribed antibiotics for the treatment of CABP. However, CABP-causing S. pneumonia are mostly resistant to currently available macrolides, so it is important to develop new treatments for the condition. Antibiotic resistance is a serious global problem which could have devastating public health consequences.