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.

Eslicarbazepine acetate (Aptiom – Sunovion) has been approved by the FDA for adjunctive treatment of partial-onset seizures in adults. New drugs for epilepsy are often approved by the FDA initially only as adjunctive treatment for partial seizures. Eslicarbazepine acetate is a prodrug of eslicarbazepine, which is the S-isomer of the active metabolite of oxcarbazepine. Oxcarbazepine itself is similar to carbamazepine. Both oxcarbazepine and carbamazepine are available generically.

Gabapentin (Neurontin - Parke-Davis), a cyclohexane acetic acid derivative, has been approved by the US Food and Drug Administration for use in addition to other antiepileptic drugs in patients with partial (focal) seizures with or without secondary generalization. Since this diagnostic category includes the largest number of patients with intractable epilepsy, new drugs with antiepileptic activity are generally tried first for this indication.

On December 22, 2021, the FDA issued an Emergency Use Authorization (EUA) for the investigational antiviral drug nirmatrelvir copackaged with the HIV-1 protease inhibitor ritonavir (Paxlovid – Pfizer) for oral treatment of mild to moderate COVID-19 in outpatients ≥12 years old who weigh at least 40 kg and are at high risk of progressing to severe disease, including hospitalization or death. Paxlovid was the first oral antiviral drug to be authorized in the US for treatment of COVID-19; Merck's oral antiviral drug molnupiravir was granted an EUA for treatment of COVID-19 on...

Patients with lung cancer may be asking their physicians about gefitinib (ge fi' tye nib; ZD1839; Iressa -- AstraZeneca), because it has been the subject of positive coverage in the media. An inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, this oral drug has not been approved by the FDA, but is in clinical trials in the US for treatment of non-small cell lung cancer (NSCLC) and some other solid tumors. Iressa was recently approved in Japan, and is available from the manufacturer on a "compassionate-use" basis in the US (800-236-9933).

Maribavir (Livtencity – Takeda), an oral cytomegalovirus (CMV) pUL97 kinase inhibitor, has been approved by the FDA for treatment of post-transplant CMV infection refractory to standard antiviral therapy in patients ≥12 years old who weigh at least 35 kg.

The FDA has approved eliglustat (Cerdelga – Genzyme), an oral glucosylceramide synthase inhibitor, for treatment of adults with type 1 Gaucher disease. Eliglustat is metabolized primarily by CYP2D6. Because patients who are CYP2D6 ultra-rapid metabolizers may not achieve therapeutic concentrations and a specific dosage cannot be recommended for indeterminate metabolizers, the FDA has approved the drug only for patients who are extensive, intermediate, or poor metabolizers of CYP2D6.

Implanon (Organon), an implantable contraceptive containing the progestin etonogestrel, has been approved by the FDA. Two other implantable contraceptives, Norplant and Jadelle, which both contain levonorgestrel, are FDA-approved but not marketed in the US.

The FDA has approved the complement factor B inhibitor iptacopan (Fabhalta – Novartis) for treatment of paroxysmal nocturnal hemoglobinuria (PNH) in adults. Iptacopan is the first oral drug to be approved in the US for this indication. Three parenterally administered drugs, the complement C5 inhibitors eculizumab (Soliris) and ravulizumab (Ultomiris) and the complement C3 inhibitor pegcetacoplan (Empaveli), are also approved for treatment of PNH.

Anticonvulsants are now widely used for treatment of psychiatric illnesses, particularly bipolar disorder. Lithium is the standard drug for treatment of bipolar disorder, but it can cause severe toxicity, serum concentrations must be monitored, and it is not effective in some patients.