Zonisamide (Zonegran - Elan Pharma), a sulfonamide chemically unrelated to other antiepileptic drugs, has been approved by the FDA for adjunctive use in adults with partial seizures. Zonisamide has been available in Japan for more than 10 years.

The FDA has approved a fixed-dose combination of meropenem, a carbapenem antibiotic, and vaborbactam, a new beta-lactamase inhibitor (Vabomere – Melinta), for IV treatment of adults with complicated urinary tract infections (UTIs) that are proven or strongly suspected to be caused by Escherichia coli, Klebsiella pneumoniae, or Enterobacter cloacae spp. complex. Meropenem (Merrem, and generics) has been approved for years for treatment of complicated skin and skin structure infections, intra-abdominal infections, and bacterial meningitis. Resistance to meropenem and other...

Duloxetine hydrochloride (Cymbalta - Lilly), a selective serotonin and norepinephrine reuptake inhibitor (SNRI) available for treatment of depression, has also been approved by the FDA for treatment of neuropathic pain associated with diabetic peripheral neuropathy (DPN). Duloxetine is one of two drugs approved specifically for management of neuropathic pain due to diabetes; the other, pregabalin (Lyrica - Pfizer), will be marketed soon and will be reviewed in the next issue of The Medical Letter.

Some recently published studies suggest that taking selective serotonin reuptake inhibitors (SSRIs) may increase the risk of developing osteoporosis. A relationship between SSRIs and osteoporosis is biologically plausible because bone has serotonin receptors, and SSRI-treated mice have reduced bone mass.

The FDA has approved extended-release (ER) calcifediol (25-hydroxyvitamin D3; Rayaldee – Opko), a prohormone of calcitriol, the active form of vitamin D3. It is indicated for treatment of secondary hyperparathyroidism (SHPT) in adults with stage 3 or 4 chronic kidney disease (CKD) who have serum total 25-hydroxyvitamin D levels <30 ng/mL.

The FDA has approved a long-acting fixed-dose combination of the stimulant dexmethylphenidate and the prodrug serdexmethylphenidate (Azstarys – Corium) for once-daily treatment of attention-deficit/hyperactivity disorder (ADHD) in patients ≥6 years old. Azstarys is the first product containing serdexmethylphenidate to become available in the US.

Gabapentin (Neurontin - Pfizer), which has been available in the US since 1994, is approved by the FDA only for treatment of partial epilepsy and postherpetic neuralgia, but is widely used off-label for a number of other indications, especially neuropathic pain syndromes. According to one report, among Medicaid recipients in Florida receiving gabapentin, 71% of prescriptions were for chronic pain and 8% for seizures and neuralgia ("The Pink Sheet" February 2, 2004; 66:30).

The FDA has approved ezogabine (ee-ZOE-ga-been; Potiga – GSK/Valeant) for oral adjunctive treatment of partial-onset seizures in adults. Ezogabine is available in Europe as retigabine (Trobalt).

Acamprosate calcium (Campral - Forest) is now being marketed for oral use to maintain abstinence from alcohol. It has been used in France and other countries since 1989.

Pregabalin (Lyrica - Pfizer), a structural analog of gamma-aminobutyric acid (GABA) similar to gabapentin (Neurontin - Pfizer, and others), which recently became available generically, has been approved by the FDA for treatment of neuropathic pain associated with postherpetic neuralgia (PHN) and diabetic peripheral neuropathy (DPN), and for adjunctive treatment of partial onset seizures in adults with epilepsy.