2 Paratek antibiotics win FDA nods, with 1 slated for $500M in peak sales

Paratek Pharmaceuticals felt double the love from the FDA this week, as two of its antibiotics won back-to-back approvals—one for Paratek itself, and the other for deal partner Allergan's dermatology buyer Almirall.

Tuesday, the FDA greenlighted Nuzyra, or omadacycline, for community-acquired bacterial pneumonia (CABP) and acute bacterial skin and skin structure infections (ABSSSI). That go-ahead followed shortly after one for Seysara, also known as sarecycline, to treat acne.

Nuzyra is a more important asset for the now commercial-stage Paretek. In a Wednesday note to investors, Leerink analyst Ami Fadia put its peak sales at over $500 million with roughly a 50-50 split between the two indications.

Boston-based Paratek has kept the drug all to itself for now. It is a modernized tetracycline that’s first in a new chemical class called aminomethycyclines, which are specifically designed to overcome tetracycline resistance. And that means it doesn’t have an in-class comparator to go up against when Paratek negotiates formulary placement.

In separate phase 3 studies, Nuzyra showed it could measure up to Pfizer’s Zyvox (linezolid) in bacterial skin infections and Bayer’s Avelox (moxifloxacin) in pneumonia. But how does Paratek plan to take on those big pharma products that have been on the market for almost two decades?

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First, doctors are increasingly pivoting away from fluoroquinolones like Avelox due to safety and resistance concerns, Evan Tzanis, Paratek’s chief development officer, recently told FiercePharma in an emailed interview.

Nuzyra comes in both intravenous and oral formulations, which means clinicians can treat patients with the IV and send them home on the pill. “This potential helps reduce hospitalizations and the costs associated with hospital stays,” said Tzanis, not to mention reducing the risk of hospital-acquired infections for these vulnerable patients.

IV-only agents sometimes spur complications such as a C. difficile infection, but no C. diff cases were observed in patients taking Nuzyra in clinical studies. Though Zyvox is also available in both IV and oral forms, it is given twice daily, compared with Nuzyra’s once-daily regimen.

Paratek is keeping mum about pricing details until the fourth quarter and looks “to price appropriately to enable formulary access,” Paratek’s chief commercial officer, Adam Woodrow, told FiercePharma. For now, it is benchmarking the drug against Zyvox before it went generic, which was about $3,000 net for a 10-day course, Woodrow said. Leerink’s Fadia currently projects $150/day for the IV and $450/day for the oral version.

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Paratek now plans to launch Nuzyra in the first quarter of next year. For the first two years, the company will focus on hospitals, and it's set eyes on about 850 hospitals that have been selected based on resistance rates, high CABP readmission rates, prescription volume and C. diff geographic density. After that, full promotion in the community might be considered, potentially with a partner, Woodrow said.

The sales force is expected to get on board soon, and Woodrow said Parartek plans to grow the team “judiciously” in 2019 toward the target of 80 to 85 reps, “which we believe is sufficient to address the key U.S. hospital accounts.”

As for Seysara, Paretek previously licensed its U.S. rights to Allergan, which just sold it, along with its medical dermatology business, to Spanish firm Almirall for up to $650 million. Almirall now expects to launch the oral tetracycline once it closes the Allergan transaction in January 2019, and it hopes to reap $150 million to $200 million in peak sales from the drug.

The FDA has hastened its antibiotic approvals in the face of ongoing antibiotic-resistance concerns. Insmed's Arikayce, an inhaled form of amikacin, just became the first drug approved under a novel pathway aimed at advancing antibacterial and antifungal agents. The agency has also waved through Tetraphase's Xerava to treat complicated intra-abdominal infections (cIAI) and Achaogen's Zemdri for drug-resistant urinary tract infections (UTI).