June 19, 2017
The US Food and Drug Administration (FDA) today approved an antibiotic called delafloxacin (Baxdela, Melinta Therapeutics) to treat serious or life-threatening infections, including one that’s particularly tough to beat.
A fluoroquinolone, delafloxacin is specifically indicated in adults with acute bacterial skin and skin structure infections (ABSSSIs) caused by certain gram-positive and gram-negative pathogens, including methicillin-resistant Staphylococcus aureus. The FDA cautions that, for the sake of curbing the development of drug-resistant bacteria, clinicians should order delafloxacin only when an infection is proven or strongly suspected to be bacterial in nature.
Delafloxacin is contraindicated for patients with known hypersensitivity to fluoroquinolones.
The new drug, administered as a tablet or through intravenous infusion, comes with a boxed warning on its label. It states that fluoroquinolones such as delafloxacin are associated with disabling and potentially irreversible adverse events such as tendinitis and tendon rupture, peripheral neuropathy, and central nervous system effects. Clinicians should discontinue the use of delafloxacin if patients experience these adverse events. They also should avoid delafloxacin in patients with a known history of myasthenia gravis, which may be exacerbated by fluoroquinolones.
The FDA determined that delafloxacin was safe and effective based on two randomized clinical trials involving roughly 1500 adults with ABSSSIs that compared the new drug with an intravenous combination of vancomycin plus aztreonam. In one study, delafloxacin was administered intravenously from start to finish, while in the other, patients started out on intravenous delafloxacin and then switched to the tablet version. In both studies, delafloxacin proved just as effective as the combination of vancomycin and aztreonam in shrinking skin lesions by at least 20% within 48 to 72 hours.
The most common adverse events seen in the clinical trials were nausea, diarrhea, headache, higher levels of transaminase, and vomiting.
The FDA had designated delafloxacin as a qualified infectious-disease product, entitling it to an expedited review.
More information about delafloxacin is available on the FDA website.