Lamotrigine (la mo tri jeen; Lamictal - Burroughs Wellcome), a phenyltriazine derivative, has been approved by the US Food and Drug Administration for use in addition to other antiepileptic drugs in adults with partial seizures. Since this diagnostic category includes the largest number of patients with intractable epilepsy, new drugs with antiepileptic activity are usually tried first for this indication. Lamotrigine was first marketed abroad in 1990 and is now available in more than 50 other countries.

The FDA has approved the oral second-generation antipsychotic drug brexpiprazole (Rexulti – Otsuka/Lundbeck) for once-daily treatment of agitation associated with dementia due to Alzheimer's disease (AD). Brexpiprazole is the first drug to be approved in the US for this indication. It is also approved for treatment of schizophrenia and as an adjunct to antidepressants for treatment of major depressive disorder.

Pravastatin - Bristol-Myers Squibb) and simvastatin (Zocor -Merck), two new inhibitors of cholesterol synthesis similar to lovastatin (Mevacor - Merck), have now been marketed in the USA for treatment of hypercholesterolemia. Lovastatin (Medical Letter, 29:99, 1987) is the most frequently prescribed of all cholesterol-lowering drugs in the USA. Pravastatin and simvastatin were previously reviewed in The Medical Letter when they became available in Canada (volume 33, page 18, 1991).

The FDA has approved fixed-dose combinations of metformin with either canagliflozin (Invokamet) or dapagliflozin (Xigduo XR) for treatment of patients with type 2 diabetes not adequately controlled with any one of these drugs, or in those already being treated with both metformin and either canagliflozin or dapagliflozin.

Moricizine (mor i'; siz een) hydrochloride (Ethmozine - Du Pont), a class I antiarrhythmic drug developed in the USSR, was recently approved by the US Food and Drug Administration (FDA) for oral treatment of life-threatening ventricular arrhythmias.

Lantaoprost, a prostaglandin F2-alpha analog, has been approved by the FDA for topical treatment of elevated intraocular pressure in patients with open-angle glaucoma and ocular hypertension refractory to other drugs.

Topiramate (Topamax - Ortho-McNeil) has been approved by the US Food and Drug Administration (FDA) for oral use as an adjunct to other drugs in adult patients with partial seizures. Since this diagnostic category includes the largest number of patients with refractory epilepsy, new drugs with antiepileptic activity are usually tried first for this indication. Topiramate (toe pyre' a mate) is a structurally unique agent chemically related to the D-enantiomer of fructose.

The FDA has approved an extended-release tablet formulation of amantadine (Osmolex ER – Vertical/Osmotica) for once-daily treatment of Parkinson's disease (PD) and drug-induced extrapyramidal symptoms (EPS) in adults. An extended-release capsule formulation of amantadine (Gocovri) was approved in 2017 for treatment of levodopa-induced dyskinesia in patients with PD.

The FDA has determined that 3 generic formulations of levothyroxine are therapeutically equivalent to brand-name formulations. Some brand-name manufacturers have objected, and endocrine organizations have expressed their concern.
See levothyroxine addendum

A once-daily oral formulation of mesalamine (Lialda - Shire) was recently approved by the FDA for induction of remission in patients with mild to moderate ulcerative colitis.