3 Small-Cap Biotechs With the Most Promising New Antibiotics in Clinical Trials


New antibiotic development seems to go through cycles. Many large companies have stayed away from antibiotics or abandoned efforts, despite a growing need for new antibiotics because of the development of antibiotic-resistant bacteria. For example, a 2014 study found that of the approximately 36 companies with antibiotics in clinical development, only five were in the top 50 pharmaceutical companies. Two of the biggest players are GlaxoSmithKline and AstraZeneca,

That said, there are smaller companies taking an interest in antibiotic development. Brian Feroldi, writing for The Motley Fool, takes a look at three small-cap biotech companies that have new antibiotics in clinical development.

1. Paratek Corp.

Based in Boston, Paratek focuses on infectious diseases, with its lead antibiotic omadacycline, a once-daily treatment in trials for community-acquired bacterial pneumonia (CABP). On Oct. 3, the company released new data from its Phase III trial of the compound, showing it was effective in adult CABP patients with the most commonly isolated pathogens, including multi-drug resistant S. pneumoniae.

Feroldi writes, “The FDA has already granted omadacycline both a Qualified Infectious Disease Product designation and Fast Track status. When combined with the upbeat Phase III data, investors have plenty of reasons to be optimistic about omadacycline’s chances.”

The company expects to submit regulatory filings in the U.S. and Europe next year.

2. Nabriva Therapeutics

Headquartered in Dublin, Ireland, with U.S. headquarters in King of Prussia, Pennsylvania, Nabriva’s lead product is lefamulin, which it hopes to be the first pleuromutilin antibiotic available for systemic administration in people. The company is working on both intravenous (IV) and oral solutions for CABP, and possibly other types of pneumonia.

On Sept. 18, the company announced positive topline results from its LEAP 1 Phase III trial of lefamulin in CABP. The LEAP 1 trial is the first of two Phase III trials. LEAP 1 compared the oral and IV formulations against each other and to moxifloxacin with or without adjunctive linezolid. It met the FDA’s primary endpoint of non-inferiority.

“These Phase III data provide strong evidence of the potential of lefamulin to treat adults with CABP and provide an alternative to a current gold standard treatment regimen,” said Colin Broom, Nabriva’s chief executive officer, in a statement.

The LEAP 2 study is just starting, and will compare oral lefamulin to moxifloxacin. Topline data is expected in early 2018.

3. Cempra

Headquartered in Chapel Hill, North Carolina, Cempra announced in early August that it was merging with Melinta Therapeutics, a New Haven, Conn.-based company that is also focused on antibiotic development. They would then create a publicly-traded company listed on the Nasdaq.

“This transaction creates a leading antibiotics company to drive the commercial launch of Baxdela, and build over time by developing market-leading pipeline assets meeting the tremendous need for novel antibiotics that treat serious infections,” said John Temperato, Melinta’s president and chief operating officer, in a statement.

The FDA approved Baxdela in June to treat acute bacterial skin and skin structure infections caused by susceptible bacteria. Baxdela is a Melinta product.

Feroldi writes, “Once upon a time, Cempra boasted a commanding lead over both Paratek and Nabriva in this race. Its next-generation antibiotic solithromycin produced encouraging Phase III data, and was submitted to the FDA for approval last year. Cempra was so confident in solithromycin’s odds of success that management had even started to build out its commercial team.”

Then the other shoe dropped and the FDA rejected the drug over concerns about liver toxicity and manufacturing. The FDA requested more data—a lot more data—from a new Phase III trial that needed to be 10 times larger than the one they based their original application on.

The merged companies are likely to be a far stronger company.

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