The FDA is requiring a boxed warning in the label of denosumab (Prolia – Amgen), a monoclonal antibody that inhibits osteoclasts, about an increased risk of severe hypocalcemia in patients with advanced chronic kidney disease (CKD; eGFR <30 mL/min/1.73 m²), particularly those on dialysis. FDA-approved indications for Prolia are listed in Table 1.

Two new drugs alendronate (Fosamax - Merck) and salmon calcitonin nasalspray (Miacalcin - Sandoz) are now available in the USA for treatment of postmenopausalosteoporosis. A third drug for treatment of osteoporosis, a slow-release fluoridepreparation (Slow Fluoride -Mission Pharmacal), has been recommended for approvalby an advisory committee of the US Food and Drug Administration (FDA). Various formulationsof fluoride have been available in Europe for this indication for many years.

The FDA recently cleared the AmpliChip CYP450 Test (Roche), which analyzes blood-derived DNA to detect genetic variations in the activity of cytochrome P450 (CYP) enzymes CYP2D6 and CYP2C19 and determines the metabolizer status of the patient. The test is intended to help guide clinicians in prescribing individualized drug therapy. About 25% of all drugs, including many antidepressants and antipsychotics, are substrates of either CYP2D6 or CYP2C19. The test is being promoted initially to psychiatrists.

A reader expressed disappointment that our recent listing of “Some Warfarin Drug Interactions”1 did not include acetaminophen. Perhaps it should have. Acetaminophen can increase the anticoagulant effect of warfarin, particularly with continued use, but it does so inconsistently. The mechanism of this interaction has not been established, but may be related to an acetaminophen metabolite inhibiting vitamin K-epoxide reductase, the target for warfarin’s anticoagulant effect.2Patient susceptibility varies, possibly on a genetic basis; occasional use of acetaminophen generally has little or...

Odevixibat (Bylvay – Albireo), an oral ileal bile acid transporter (IBAT) inhibitor, has been approved by the FDA for treatment of pruritus in patients ≥3 months old with progressive familial intrahepatic cholestasis (PFIC). It is the first drug to be approved in the US for this indication.

The oral biguanide metformin (Glucophage, and others) is generally the drug of choice for initial treatment of type 2 diabetes. It has also been used to prevent or at least delay the onset of diabetes in patients considered to be at high risk for the disease. Recent guidelines recommend considering use of metformin in patients with prediabetes (fasting plasma glucose 100-125 mg/dL, 2-hr post-load glucose 140-199 mg/dL, or A1C 5.7-6.4%), especially in those who are <60 years old, have a BMI >35 kg/m2, or have a history of gestational diabetes. Metformin has not been approved...

The US Food and Drug Administration (FDA) has approved two new retinoids for treatment of psoriasis. Tazarotene gel 0.05% and 0.1% (Tazorac - Allergan) is being marketed for topical use in patients with stable, mild to moderate plaque psoriasis. Acitretin (Soriatane - Roche) is being promoted for systemic use in severe psoriasis.

The FDA has approved vutrisiran (Amvuttra – Alnylam), a subcutaneously injected small interfering RNA (siRNA), to reduce cardiovascular hospitalizations, urgent heart failure visits, and cardiovascular death in adults with wild-type or variant transthyretin amyloid cardiomyopathy (ATTR-CM). Vutrisiran is the first siRNA to be approved in the US for this indication; it was approved earlier for treatment of polyneuropathy associated with hereditary transthyretin-mediated amyloidosis.

Bexarotene, a retinoid analog, has been approved by the US Food and Drug Administration for oral treatment of dermatologic manifestations of refractory cutaneous T-cell lymphoma.

Warfarin sodium (Coumadin, and others) and other coumarin anticoagulants prevent thrombosis, but patient response is highly variable and overanticoagulation can lead to hemorrhage. Genotyping patients for single nucleotide polymorphisms (SNPs) that affect coumarin metabolism and sensitivity may help clinicians estimate the therapeutic warfarin dose. The FDA has added a note to warfarin labeling recommending lowrange doses for patients with such genetic variations. Commercial tests for these variants are now available and cost about $500 per test.