Sevelamer carbonate (Renvela – Genzyme), a buffered form of the anion-exchange resin sevelamer hydrochloride (Renagel – Genzyme),1 has been approved by the FDA for use in patients with chronic kidney disease on dialysis. According to the manufacturer, Renvela will replace Renagel, which has been shown to induce or exacerbate metabolic acidosis in patients on dialysis. Two randomized, crossover studies found the two sevelamer salts equivalent in their ability to lower serum phosphate.2,3 Patients taking the carbonate had higher serum bicarbonate concentrations and fewer gastrointestinal...

The goal for drug therapy of type 2 diabetes is achieving and maintaining a near-normal glycated hemoglobin (HbA1C) concentration without inducing hypoglycemia; the target has generally been an HbA1C of 6.5-7.0% or lower. Whether treating to this level prevents macrovascular (cardiovascular) events has been unclear. Now, 2 large randomized, double-blind trials in patients with long-standing diabetes and at high risk for cardiovascular disease have found no decrease in macrovascular events with intensive glucose control.The ACCORD trial in about 10,000 patients found that patients intensively...

The thionamides propylthiouracil and methimazole are both used to treat hyperthyroidism.1 Propylthiouracil causes severe hepatic toxicity or hepatic failure in about 0.1% of adults and children.2,3 It is the third leading cause of liver transplants due to drug toxicity (acetaminophen and isoniazid are the first two). Methimazole may cause less serious hepatic toxicity; reversible cholestatic jaundice has been reported. There is generally no good reason to continue to use propylthiouracil, with 2 possible exceptions. First, propylthiouracil may be preferred for treatment of life-threatening...

Some readers have asked why the June 2009 issue of Treatment Guidelines (Antimicrobial Prophylaxis for Surgery) did not recommend use of ertapenem (Invanz) for prevention of infection after elective colorectal surgery. Ertapenem is a broad-spectrum carbapenem that has been approved for such use by the FDA. Medical Letter consultants do not recommend use of broad-spectrum drugs such as ertapenem, third-generation cephalosporins such as cefotaxime (Claforan), ceftriaxone (Rocephin), cefoperazone (Cefobid), ceftazidime (Fortaz, and others) or ceftizoxime (Cefizox), or fourth-generation...

In the Medical Letter article on ustekinumab (Stelara) for psoriasis (2010; 52:7), footnote 2 in table 2 should have included a second sentence: $5595.60 is the cost of one 45-mg syringe.

The FDA has approved spinosad 0.9% suspension (Natroba – ParaPro) for topical treatment of head lice infestation in patients ≥4 years old. It is available only by prescription.

The FDA has approved a once-daily extended-release (ER) formulation of the antiepileptic topiramate (Trokendi XR – Supernus) for initial monotherapy in patients ≥10 years old with partial onset seizures or primary generalized tonic-clonic seizures and for adjunctive therapy in patients ≥6 years old with partial onset seizures, primary generalized tonic-clonic seizures, or seizures associated with Lennox-Gastaut syndrome. Topiramate has been available for many years as an immediate-release (IR) formulation (Topamax, and generics) for the same indications in patients ≥2...

The FDA has approved Descovy (Gilead), a fixed-dose combination of the nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) emtricitabine (FTC) and tenofovir alafenamide (TAF) for use with other antiretroviral agents for treatment of HIV-1 infection. A combination of emtricitabine and tenofovir disoproxil fumarate (FTC/TDF; Truvada) has been available since 2004 for the same indication. Emtricitabine and TAF are also available in combination with the non-nucleoside reverse transcriptase inhibitor (NNRTI) rilpivirine as Odefsey and with the integrase strand transfer...

The FDA has approved crisaborole 2% ointment (Eucrisa – Pfizer) for topical treatment of mild to moderate atopic dermatitis in patients ≥2 years old. It is the first phosphodiesterase type-4 (PDE4) inhibitor to be approved in the US for this indication.

Aducanumab-avwa (Aduhelm – Biogen/Eisai), an IV amyloid beta-directed monoclonal antibody, has received accelerated approval from the FDA for treatment of Alzheimer's disease. The approval was based on the surrogate endpoint of reduction in amyloid beta plaques in the brain. The manufacturer is required to conduct an additional randomized controlled trial to establish that reducing amyloid beta plaques with aducanumab improves clinical outcomes in patients with Alzheimer's disease.