Itraconazole (Sporanox - Janssen), an antifungal triazole, has been approved by the US Food and Drug Administration (FDA) for oral treatment of histoplasmosis and blastomycosis. These two endemic mycoses occur both in normal hosts and in immunocompromised patients, such as those with AIDS (RW Bradsher, Clin Infect Dis, 14:S82, 1992; LJ Wheat, Clin Infect Dis, 14:S91, 1992).

Zonisamide (Zonegran - Elan Pharma), a sulfonamide chemically unrelated to other antiepileptic drugs, has been approved by the FDA for adjunctive use in adults with partial seizures. Zonisamide has been available in Japan for more than 10 years.

Serious adverse interactions between drugs continue to be reported. Many of these are due to inhibition or induction of cytochrome P450 (CYP) enzymes, particularly CYP3A4. CYP3A is thought to be involved in the metabolism of more than 50 percent of currently prescribed drugs.2 CYP3A4, which is more abundantly expressed than CYP3A5, accounts for most CYP3A activity in vivo.

Erlotinib (Tarceva) is the second oral epidermal growth factor receptor (EGFR) inhibitor to become available in the US for treatment of advanced refractory NSCLC. In clinical trials, erlotinib produced a response rate of only 8.9%, but increased median survival from 4.7 to 6.7 months. Patients who had never smoked and those with EGFR-positive tumors survived longer. Erlotinib is generally well tolerated; diarrhea and rash are the most common adverse effects.

A recent letter to the editor of the Annals of Internal Medicine documented a single case of myopathy apparently due to an interaction between simvastatin (Zocor, and others) and green tea. Since it became available generically, simvastatin has surpassed atorvastatin (Lipitor) as the best selling statin. As such, it is probably the most common cause of statin-induced myopathy, which is often a result of drug interactions.

Rufinamide (Banzel - Eisai), a triazole derivative structurally unrelated to other marketed antiepileptic drugs (AEDs), has been approved by the FDA for treatment of seizures associated with Lennox-Gastaut syndrome (LGS) in patients ≥4 years old.

Dronedarone (Multaq - Sanofi-Aventis) has been approved by the FDA for oral treatment of atrial fibrillation and flutter. Amiodarone (Cordarone, and others) is the most effective drug for this indication, but has considerable toxicity.

Ifosfamide (Ifex - Mead Johnson), a synthetic analog of cyclophosphamide (Cytoxan; and others), has been approved by the US Food and Drug Administration (FDA) for concurrent use with other drugs in third-line chemotherapy of metastatic germ-cell testicular cancer. Given concomitantly, a synthetic sulfhydryl compound known as mesna (Mesnex - Asta) acts in the urine to detoxify metabolites of ifosfamide that cause hemorrhagic cystitis (H Burkert, Cancer Treat Rev, 10 suppl A:175, 1983). Ifosfamide and mesna are available together from Bristol-Myers Oncology Division.

The FDA has approved lacosamide (Vimpat - UCB Pharma) for oral or intravenous (IV) use as add-on therapy in adults with partial-onset seizures.

Bupropion (Wellbutrin - Burroughs Wellcome) was recently marketed in the USA for treatment of depression. First approved by the Food and Drug Administration in late 1985, the drug was withdrawn from the market in early 1986 because of a high incidence of seizures in one study.