Ambrisentan (Letairis - Gilead), a selective endothelin type A (ET_A) receptor antagonist, has been approved by the FDA for treatment of symptomatic patients (WHO class II or III) with pulmonary arterial hypertension (PAH).

Romiplostim (Nplate - Amgen), a recombinant fusion protein injected subcutaneously, and eltrombopag (Promacta - GlaxoSmithKline), a non-peptide taken orally, have been approved by the FDA for treatment of chronic immune thrombocytopenic purpura (ITP) refractory to corticosteroids, immunoglobulins and/or splenectomy.

Concerns have surfaced again at the FDA and in the media about the safety of acetaminophen and the multiplicity of products on the market in the US that contain various amounts of it.

The FDA has licensed two new pneumococcal conjugate vaccines (PCVs) for prevention of invasive pneumococcal disease in adults: Prevnar 20 (PCV20; Pfizer), which contains antigens from 20 serotypes of pneumococcus, and Vaxneuvance (PCV15; Merck), which contains antigens from 15 serotypes. Two other pneumococcal vaccines are available in the US: Prevnar 13 (PCV13; Pfizer), a 13-valent conjugate vaccine licensed for use in persons ≥6 weeks old, and Pneumovax 23 (PPSV23; Merck), a 23-valent pneumococcal polysaccharide vaccine licensed for use in persons ≥2 years...

Sertraline (Zoloft - Roerig), a serotonin reuptake inhibitor, was recently approved for marketing by the US Food and Drug Administration for treatment of depression. Another serotonin reuptake inhibitor, fluoxetine (Prozac), is prescribed more frequently in the USA than any other antidepressant (Medical Letter, 32:83, 1990).

Finasteride (Proscar - Merck) has now been approved by the US Food and Drug Administration (FDA) for oral treatment of benign prostatic hyperplasia. A 4-aza-steroid, the drug is a specific inhibitor of steroid 5 -reductase, the enzyme that catalyzes conversion of testosterone to dihydrotestosterone. Dihydrotestosterone is required for development and maintenance of prostatic hypertrophy (JS Tenover, Endocrinol Metab Clin North Am, 20:893, 1991).

Zolpidem (Ambien - Searle), an imidazopyridine hypnotic available in Europe for several years, was recently approved by the US Food and Drug Administration for short-term treatment of insomnia.

Loratadine (Claritin - Schering), a new H 1 -receptor antagonist, has been approved by the U.S. Food and Drug Administration for treatment of seasonal allergic rhinitis in patients more than 12 years old. It will compete with older, relatively sedating drugs such as chlorpheniramine (Chlor-Trimeton, and others) and clemastine (Tavist - Medical Letter, 35:9, 1993) and with newer relatively non-sedating agents such as terfenadine (Seldane) and astemizole (Hismanal).

Isosorbide mononitrate, the major active metabolite of isosorbide dinitrate, was first approved in the USA for oral use in patients with chronic stable angina in 1992 (Medical Letter, 34:61, 1992). Now an extended-release formulation of isosorbide mononitrate (Imdur -Key) has been approved by the US Food and Drug Administration.

Fluvastatin (Lescol - Sandoz), an HMG-CoA reductase inhibitor, was recently marketed in the USA for treatment of hypercholesterolemia. A synthetic mevalonolactone derivative, it is chemically distinct from previously available drugs in this class.