The FDA has approved inclisiran (Leqvio – Novartis), a small interfering RNA (siRNA) directed to proprotein convertase subtilisin/kexin type 9 (PCSK9) mRNA, as an adjunct to diet and maximally tolerated statin therapy for subcutaneous (SC) treatment of adults with heterozygous familial hypercholesterolemia (HeFH) or clinical atherosclerotic cardiovascular disease (ASCVD) who require additional lowering of low-density lipoprotein cholesterol (LDL-C). Inclisiran is the first FDA-approved PCSK9-directed siRNA therapeutic agent.

Seladelpar (Livdelzi – Gilead), a peroxisome proliferator-activated receptor (PPAR)-delta agonist, has received accelerated approval from the FDA for use in combination with ursodeoxycholic acid (ursodiol, UDCA; Urso Forte, and generics) for treatment of primary biliary cholangitis (PBC) in adults who had an inadequate response to UDCA and as monotherapy in those unable to tolerate UDCA. Accelerated approval was based on a reduction in alkaline phosphatase (ALP) levels. Seladelpar is the second PPAR agonist to be approved in the US for this indication; elafibranor (Iqirvo)...

Vasodilators are widely used for treatment of congestive heart failure (CHF) that has not responded adequately to diuretics and digitalis. Vasodilator drugs redistribute blood volume in patients with heart failure, lowering pressure and reducing volume in the failing left ventricle, which leads to increased cardiac output, decreased pulmonary capillary wedge pressure, and improved exercise tolerance. Since the last Medical Letter review of this subject (Volume 26, page 115, 1984), some additional data have become available.

Astemizole (Hismanal - Janssen), a new antihistamine, was recently marketed in the USA for treatment of seasonal allergic rhinitis and chronic idiopathic urticaria. Like terfenadine (Seldane - Medical Letter, 27:65, 1985), astemizole is claimed to be no more sedating than placebo, but the new drug offers the advantage of a once-daily dosage schedule.

An aqueous formulation of alprostadil (prostaglandin E 1 ; - Upjohn) has been approved by the US Food and Drug Administration (FDA) for injection into the corpus cavernosum to treat erectile dysfunction. The drug is also marketed as Prostin VR, an alcohol-containing formulation, for intravenous use in newborns with congenital heart disease to maintain the patency of the ductus arteriosus.

The FDA recently announced that it was investigating 38 reports of loss of vision in men who took sildenafil (Viagra), which has been used to treat erectile dysfunction since 1998.

In recent months, both the lay media and some medical experts have raised concerns about the effectiveness and safety of ezetimibe, a widely used drug that prevents absorption of cholesterol from the GI tract. Ezetimibe is available alone as Zetia and in combination with 10, 20, 40 and 80 mg of simvastatin (Zocor, and others) as Vytorin.

The FDA has approved ospemifene (os pem’ i feen; Osphena – Shionogi), an estrogen agonist/antagonist, for oral treatment of moderate to severe dyspareunia in postmenopausal women. Ospemifene is the fourth estrogen agonist/antagonist to be marketed in the US, but it is the only one that has an estrogen-like effect on vaginal epithelium. The other three, tamoxifen (Nolvadex, and generics), toremifene (Fareston), and raloxifene (Evista), are used for treatment and prevention of breast cancer and osteoporosis.

The FDA has approved a higher-dose intranasal naloxone formulation (Kloxxado – Hikma) for emergency treatment of opioid overdose. A single spray of the new formulation delivers 8 mg of naloxone; a formulation that delivers 4 mg per spray (Narcan) was approved in 2015.

Adagrasib (Krazati – Mirati Therapeutics), a RAS GTPase family inhibitor, has received accelerated approval from the FDA for oral treatment of KRAS G12C-mutated locally advanced or metastatic non-small cell lung cancer (NSCLC) in adults who received at least one prior systemic therapy. Accelerated approval was based on the objective response rate and duration of response.