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.

Bosentan (Tracleer - Actelion), a non-peptide endothelin receptor antagonist, has been approved by the FDA for oral treatment of patients who have pulmonary arterial hypertension (PAH) with symptoms of dyspnea at rest or with minimal exertion.

Modafinil (Provigil - Cephalon; Alertec - Draxis in Canada), first approved by the FDA in 1999 for treatment of excessive daytime sleepiness associated with narcolepsy (Medical Letter 1999; 41:30), has now also been approved for treatment of patients with excessive sleepiness due to obstructive sleep apnea/hypopnea syndrome (OSAHS) or shift work sleep disorder (SWSD) (DSM-IV, text revision, Washington, DC: American Psychiatric Association, 2000, page 622).

Implanon (Organon), an implantable contraceptive containing the progestin etonogestrel, has been approved by the FDA. Two other implantable contraceptives, Norplant and Jadelle, which both contain levonorgestrel, are FDA-approved but not marketed in the US.

The FDA has approved an oral, fixed-dose combination (Treximet - GlaxoSmithKline) of the selective serotonin receptor agonist ("triptan") sumatriptan (Imitrex) and the nonsteroidal anti-inflammatory drug (NSAID) naproxen sodium (Anaprox, and others) for acute treatment of migraine attacks.

The FDA has approved the marketing of tolvaptan (Samsca - Otsuka), an oral vasopressin receptor antagonist, for treatment of hypervolemic or euvolemic hyponatremia due to congestive heart failure (CHF), cirrhosis or the syndrome of inappropriate antidiuretic hormone secretion (SIADH). A similar drug, conivaptan (Vaprisol) is already available for intravenous (IV) treatment of euvolemic hyponatremia in hospitalized patients. Tolvaptan was approved by the FDA for both inpatient and outpatient use, but it should be started in a hospital.

Three rapid-acting insulin analogs are currently available: insulin lispro, insulin aspart and insulin glulisine. 1-3 All three are approved for use in both type 1 and type 2 diabetes, either by subcutaneous injection, insulin pump or intravenous administration. All three cost more than regular insulin.

Armodafinil (Nuvigil – Cephalon), the R-enantiomer of the non-amphetamine stimulant modafinil (Provigil – Cephalon; Alertec – Shire in Canada), is being promoted directly to the public for treatment of excessive daytime sleepiness associated with shift work.

Mirabegron (mir a beg’ ron; Myrbetriq [meer BEH trick] – Astellas), a beta-3 adrenergic agonist, has been approved by the FDA for the treatment of overactive bladder. It is the first beta-3 adrenergic agonist to be approved for any indication in the US. Mirabegron has been marketed in Japan since 2011. OnabotulinumtoxinA (Botox) was also recently approved by the FDA for treatment of overactive bladder and will be reviewed in a future issue.

Rifaximin (Xifaxan – Salix), a minimally absorbed oral antibiotic approved previously to treat travelers' diarrhea and to reduce the risk of recurrent hepatic encephalopathy, has now been approved by the FDA for treatment of irritable bowel syndrome with diarrhea (IBS-D). Eluxadoline (Viberzi – Actavis), a mu-opioid receptor agonist, was also recently approved for IBS-D and will be reviewed in a future issue.