Zafirlukast (za fir loo kast; Accolate - Zeneca), the first leukotriene receptor anta-gonist approved by the US Food and Drug Administration, is now being heavily promoted for oral maintenance treatment of chronic asthma in patients more than 12 years old. It is not recommended for treatment of acute asthma.

The oral sphingosine 1-phosphate (S1P) receptor modulator etrasimod (Velsipity – Pfizer) has been approved by the FDA for treatment of moderately to severely active ulcerative colitis in adults. It is the second oral S1P receptor modulator to be approved in the US for this indication; ozanimod (Zeposia) was the first.

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.

The drugs of choice for treatment of common cardiac arrhythmias are listed in Tables 1 and 2. Some drugs are recommended for indications that have not been approved by the FDA.

Recent advertisements for indapamide (Lozol - Rorer), an oral antihypertensive/diuretic (Medical Letter, 26:17, 1984), claim that the drug, unlike thiazide diuretics, does not significantly increase serum cholesterol and has a minimal impact on potassium. Indapamide has no thiazide ring but, like chlorthalidone (Hygroton; and others) and hydrochlorothiazide (HydroDiuril; and others), it does have a sulfamoyl benzamide moiety, which is probably responsible for its natriuretic and diuretic effects. Unlike the thiazides, it also has a methylindoline moiety, which apparently decreases...

The equivalence of generic drugs to their brand-name precursors continues to be controversial. The last Medical Letter review of this subject (2002) concluded that well-documented therapeutic inequivalence between brand-name and FDA-approved generic drugs had not been reported. Is that still true? New data have become available for some drugs.

Treprostinil sodium (tre prost' in il; Remodulin - United Therapeutics), a prostacyclin analogue, has been approved by the FDA for continuous subcutaneous (SC) treatment of patients with pulmonary arterial hypertension who have dyspnea on more than minimal exertion (NYHA Class II-IV).

Serious adverse interactions between drugs continue to be reported. Many of these are due to inhibition or induction of cytochrome P450 (CYP) enzymes, particularly CYP3A4. CYP3A is thought to be involved in the metabolism of more than 50 percent of currently prescribed drugs.2 CYP3A4, which is more abundantly expressed than CYP3A5, accounts for most CYP3A activity in vivo.

View the Table: Some Drug Interactions with Drugs for IBD

The FDA has approved mavacamten (Camzyos – MyoKardia/BMS), a modulator of cardiac myosin, to improve functional capacity and symptoms in adults with New York Heart Association (NYHA) class II or III obstructive hypertrophic cardiomyopathy (HCM) who have a baseline left ventricular ejection fraction (LVEF) ≥55%. Mavacamten is the first drug in its class to become available in the US.