More than two decades after it was first synthesized in a lab, omadacycline is finally being reviewed by the FDA for its potential as a broad-spectrum antibiotic.
It’s a long-awaited milestone for Dr. Evan Loh, who serves as president, COO and CMO of Paratek Pharmaceuticals (NSDQ:PRTK), the company developing and commercializing omadacycline. It’s also emblematic of why so many pharmaceutical companies have pivoted away from the antibiotic space.
“Most antibiotics do not become profitable until the third year after their launch,” Loh told Drug Delivery Business News. “From a big-pharma perspective, that level of delay in terms of reaching profitability – where it will actually go to their bottom line, given their overhead – it makes this space relatively less attractive.”
But the antibiotic arena is in desperate need of innovation. As certain strains of bacteria become more resistant to drugs, doctors need new products to treat their patients.
Paratek hopes that omadacycline, which it describes as the first in a new class of antibiotics, will help relieve some of the stress felt by communities burdened by antibiotic-resistant bugs.
The company, which was started in 1996 by Tufts University professor Stuart Levy and Wally Gilbert, a Nobel Prize winner and Biogen (NSDQ:BIIB) co-founder, is developing its lead product candidate to fight community-acquired bacterial infections, such as pneumonia and bacterial skin infections.
The FDA gave omadacycline fast-track status and qualified infectious disease product designation for its target indications: community-acquired bacterial pneumonia, acute bacterial skin and skin structure infections and urinary tract infections.
The drug is designed to overcome the hurdles faced by tetracycline – a class of antibiotics that doctors have been prescribing since the 1950s for an array of problems. But over time, its extensive use has helped fuel bacterial resistance, leaving its effectiveness limited to just a few types of infections.

Paratek’s omadacycline is made using two alterations to tetracycline’s chemical structure, according to Loh, so the product maintains tetracycline’s safety and efficacy while sidestepping the problem of resistance.
“It’s not a panacea,” Loh said, acknowledging that just like any antibiotic, omadacycline won’t be right for all patients. Paratek has developed an intravenous version of omadacycline, as well as an oral formulation. The different options are part of Paratek’s “go home, stay home” strategy. If a patient comes to the hospital with a bacterial skin infection or bacterial pneumonia, they could be treated with the IV omadacycline for just one or two days before being sent home with the oral equivalent.
The company also ran a trial evaluating the product’s efficacy if patients skip the IV omadacycline step and are just sent home with the oral version.
“These were equally sick patients, but our efficacy rates were as good, if not a little better than what we saw with a combination of the intravenous and the oral,” Loh said.
Looking ahead, Paratek hopes to land FDA approval for omadacycline by the end of 2018 and launch the product in the first quarter of 2019. The company also plans to start its Phase II program for the IV and oral omadacycline formulation in patients with urinary tract infections.
Loh said that ultimately, every antibiotic will be subject to resistance – including omadacycline. But there are strategies that hospitals and healthcare workers can employ to help delay the process.
“Bugs always win,” he said. “I think there’s a fallacy around broad-spectrum antibiotics, that the use of broad-spectrum antibiotics leads to resistance. I think that’s actuallly not right. In a sense, the one that leads to antibiotic resistance is the wrong antibiotic, because if you’re not treated with the right one, the bug doesn’t get cured and it doesn’t get eliminated from your system.”
And although diagnostic technologies are getting better at quickly pin-pointing what type of bacteria is causing an infection, Loh says he still sees a strong argument for the use of broad-spectrum antibiotics.
“People talk about the nirvana of always knowing what the bug is in diagnostics, but at the end of the day, for the first 48 to 72 hours, you don’t know what the bug is,” he said. “And when you don’t know what the bug is and when you’re really sick, guess what? Every doctor will use a broad-spectrum antibiotic.”