Salmeterol xinafoate (Serevent - Allen & Hanburys), a long-acting β 2 -selective adrenergic agonist for inhalation, has been approved by the US Food and Drug Administration for maintenance treatment of asthma, with or without concurrent use of inhaled corticosteroids. Salmeterol is not recommended for acute treatment of bronchospasm.

Several recent case reports suggest that oral sildenafil may be effective for treatment of pulmonary arterial hypertension (PAH). Sildenafil is currently marketed as Viagra for treatment of erectile dysfunction (Medical Letter 1998; 40:51).

immune globulin (human) has been available for many years in an intramuscular (IM) formulation for prevention of Rh isoimmunization in pregnant Rh-negative women (Medical Letter, 16:3, 1974). Recently, the US Food and Drug Administration (FDA) approved the first intravenous (IV) immune globulin preparation (WinRho SD - Univax), not only for preventing Rh isoimmunization, but also for treatment of immune thrombocytopenic purpura (ITP) in Rh-positive patients.

The FDA has approved the immune checkpoint inhibitor atezolizumab (Tecentriq – Genentech) for treatment of locally advanced or metastatic urothelial carcinoma and metastatic non-small cell lung cancer (NSCLC) that have progressed during or following platinum-based chemotherapy. Atezolizumab is the first programmed death-ligand 1 (PD-L1) blocking antibody to become available in the US. Two other immune checkpoint inhibitors, the programmed death receptor-1 (PD-1) inhibitors nivolumab (Opdivo) and pembrolizumab (Keytruda), are also approved for treatment of metastatic NSCLC, and...

Pravastatin (Pravachol - Bristol-Myers Squibb) and simvastatin (Zocor - Merck), two new inhibitors of cholesterol synthesis similar to lovastatin (Mevacor - Merck), have been marketed in Canada and several European countries and may soon be available in the USA for treatment of high plasma cholesterol concentrations. Drugs already marketed here for this indication were recently reviewed in The Medical Letter (Volume 33, page 1, January 11, 1991).

Rosiglitazone, the second thiazolidinedione derivative to be marketed in the USA for treatment of type 2 diabetes, has been approved by the FDA for use either alone or combined with meformin.

The FDA has approved use of gamma hydroxybutyrate (sodium oxybate is the official generic name; Xyrem - Orphan Medical) for oral treatment of cataplexy in patients with narcolepsy. Gamma hydroxybutyrate (GHB), a metabolite of gamma-aminobutyric acid (GABA), is a central-nervous-system depressant marketed in Europe for use in general anesthesia. In recent years it has been notorious for its use in "date-rape" (Medical Letter 2002; 44:21). Xyrem is a Schedule III controlled substance.

The FDA recently approved the monoamine oxidase inhibitor (MAOI) selegiline in a transdermal (patch) formulation (Emsam - Bristol-Myers Squibb/Somerset) for treatment of major depressive disorder. Selegiline is also available in an oral formulation (Eldepryl, and others) for treatment of Parkinson's disease.

Ropinirole (Requip - GlaxoSmithKline), a dopamine agonist already available for treatment of Parkinson's disease, is now the first drug approved by the FDA for treatment of moderate to severe restless legs syndrome (RLS).

The FDA has approved pitolisant (Wakix – Harmony), a histamine-3 (H₃)-receptor antagonist/inverse agonist, for treatment of excessive daytime sleepiness (EDS) or cataplexy in adults with narcolepsy. It is the first H₃-receptor antagonist/inverse agonist to become available in the US and the first non-controlled substance to receive FDA approval for these indications. Pitolisant has been available in Europe since 2016.