The Medical Letter reported last year that sildenafil (Viagra - Pfizer) appeared to be effective for idiopathic pulmonary arterial hypertension (PAH), but confirmation from a controlled trial was needed. Now the results of such a study are about to be published, and the drug has been approved by the FDA for this indication under the trade name Revatio.

The FDA has approved use of tadalafil (Adcirca - Lilly/United Therapeutics) for treatment of pulmonary arterial hypertension (PAH).

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).

A reader asked us to review use of the phosphodiesterase-5 (PDE5) inhibitor sildenafil for treatment of Alzheimer's disease (AD).

The FDA has approved a sublingual powder formulation of nitroglycerin (GoNitro – Espero) for prevention or acute relief of an attack of angina pectoris. It is the first powder formulation of nitroglycerin to become available in the US. Most patients with angina use sublingual nitroglycerin tablets (Nitrostat, and generics). Translingual spray formulations of nitroglycerin (NitroMist, Nitrolingual Pumpspray, and generics) are also available.

The FDA has approved macitentan (ma" si ten' tan; Opsumit – Actelion), for oral treatment of pulmonary arterial hypertension (PAH). Macitentan is the second nonselective endothelin receptor antagonist approved for PAH. It is a derivative of bosentan (Tracleer), which is also manufactured by Actelion, and is scheduled to become available generically in 2015. Riociguat (Adempas), another new drug for this indication, will be reviewed in a future issue. Volibris

BiDil (NitroMed), a fixed-dose combination of isosorbide dinitrate and hydralazine, was approved by the FDA for adjunctive use in the treatment of heart failure in black patients.Both drugs are oral vasodilators that have been used together off-label for many years to treat heart failure in patients not responding to other drugs.

The FDA has approved the sGC stimulator riociguat (rye" oh sig' ue at; Adempas – Bayer) for oral treatment of pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) following surgery or when surgery is not an option. It is the first drug to be approved for treatment of CTEPH.

The FDA has approved sotatercept-csrk (Winrevair – Merck), a first-in-class activin signaling inhibitor, to increase exercise capacity, improve WHO functional class, and reduce the risk of clinical worsening events in adults with WHO Group 1 pulmonary arterial hypertension (PAH).

The FDA has approved a lingual aerosol formulation of nitroglycerin (NitroMist – Akrimax) for acute relief of an attack or acute prophylaxis of angina pectoris. It is the second nitroglycerin lingual spray to become available in the US; Nitrolingual Pumpspray was approved in 1985. Most patients with angina use sublingual nitroglycerin tablets.