Azilsartan medoxomil, belimumab, and lurasidone hydrochloride

Abstract

Antihypertensive agent Azilsartan medoxomil (Edarbi—Takeda) is the eighth angiotensin II receptor blocker (ARB) to be marketed in the United States, joining candesartan cilexetil (Atacand), eprosartan (Teveten), irbesartan (Avapro), losartan (e.g., Cozaar), olmesartan medoxomil (Benicar), telmisartan (Micardis), and valsartan (Diovan). The ARBs directly block the binding of the potent vasoconstrictor angiotensin II to its receptor sites, thereby causing a reduction in blood pressure. All of the ARBs selectively block the AT1 subtype angiotensin II receptors. The form of azilsartan that is used in its tablet formulation is the potassium salt of azilsartan medoxomil, which also is known as azilsartan kamedoxomil. Like candesartan cilexetil and olmesartan medoxomil, azilsartan medoxomil is a prodrug, and the new agent is hydrolyzed to azilsartan in the gastrointestinal tract during absorption. As with the other ARBs, azilsartan is indicated for the treatment of hypertension and may be used alone or in combination with other antihypertensive agents, most often a diuretic. In studies in which it was compared with olmesartan and valsartan, azilsartan was more effective in lowering 24-hour blood pressure. The reduction in the 24-hour mean systolic blood pressure was 14.3 mm Hg with azilsartan (80 mg once a day), compared with reductions of 11.7 and 10 mm Hg with olmesartan (40 mg/day) and valsartan (320 mg/day), respectively. As with the other ARBs, azilsartan was less effective in lowering blood pressure in black patients. In addition to hypertension, certain of the ARBs also have been approved for additional indications (e.g., valsartan for the treatment of heart failure in patients who are intolerant of angiotensin-converting enzyme inhibitors [ACEIs], candesartan and losartan for the treatment of diabetic nephropathy in patients with type 2 diabetes and hypertension). However, these are not labeled indications for azilsartan at the present time. Like the other ARBs, azilsartan is well tolerated, with diarrhea (2%) being the most common adverse event reported in the clinical studies. Although the ARBs are not likely to cause symptomatic hypotension, caution should be exercised when azilsartan is used in volumeor salt-depleted patients (e.g., those using diuretics), and the use of a lower dosage should be considered. The ARBs have a potential to cause changes in renal function, and azilsartan should be used with caution in patients who are at greatest risk of such a response (e.g., those with preexisting renal impairment or renal artery stenosis). The concurrent use of a nonsteroidal anti-inflammatory drug (NSAID) may result in a deterioration of renal function in at-risk patients. In addition, the antihypertensive effect of azilsartan may be reduced by NSAIDs. Neonatal morbidity and death are risks if either an ARB or ACEI is used during the second or third trimesters of pregnancy, and this is addressed in a boxed warning in the labeling for these agents. Like the other agents, azilsartan is classified in Pregnancy Categories C (first trimester) and D (second and third trimesters). If a woman treated with one of these agents becomes pregnant, treatment should be discontinued as soon as possible. Whether azilsartan is excreted in human milk is unknown; therefore, in nursing mothers, a decision should me made whether to discontinue nursing or not use the drug. The effectiveness and safety of azilsartan in pediatric patients have not been established. Following oral administration, azilsartan medoxomil is rapidly hydrolyzed to azilsartan, the absolute bioavailability of which is approximately 60%. It is metabolized to two primary metabolites, primarily via the cytochrome P450 (CYP)2C9 pathway, but the metabolites do not contribute to the activity of the drug. Approximately 55% of the drug is recovered in the feces and approximately 40% in the urine. Dosage adjustment is not considered necessary in patients with impaired renal function or in patients with mild or moderate hepatic impairment. The new drug has not been studied in patients with severe hepatic impairment. The recommended dosage of azilsartan is 80 mg once a day, with or without food. In patients who are also being treated with a diuretic in a high dosage, consideration should be given to initiating treatment with azilsartan in a dosage of 40 mg once a day. Azilsartan kamedoxomil is supplied in tablets in quantities representing the equivalent of 40 and 80 mg of azilsartan medoxomil. The tablets should be dispensed and stored in the original container to protect the drug from light and moisture and should not be repackaged. A combination formulation that also includes a diuretic is under development.