Posaconazole (Noxafil - Schering-Plough), an oral azole antifungal with a chemical structure similar to that of itraconazole (Sporanox), has been approved by the FDA to prevent Candida and Aspergillus infections in severely immunocompromised patients and for treatment of oropharyngeal candidiasis. It is likely also to be used off-label for treatment of other fungal infections, including those caused by Mucor and other Zygomycetes.

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.

The 1.5% cream formulation of the Janus kinase (JAK) inhibitor ruxolitinib (Opzelura – Incyte) has been approved by the FDA for topical treatment of nonsegmental vitiligo (NSV) in patients ≥12 years old. Opzelura is the first product to be approved by the FDA for this indication. It was previously approved for treatment of atopic dermatitis.

The FDA has approved a 0.3% foam formulation of the phosphodiesterase-4 (PDE4) inhibitor roflumilast (Zoryve – Arcutis) for topical treatment of seborrheic dermatitis in patients ≥9 years old. Roflumilast is the first PDE4 inhibitor to be approved in the US for this indication. It is also available in a 0.3% cream formulation (Zoryve) for treatment of plaque psoriasis and in an oral formulation (Daliresp, and generics) for treatment of chronic obstructive pulmonary disease. A 0.15% cream formulation for treatment of atopic dermatitis in patients ≥6 years old will be reviewed...

Changes caused by one drug in the absorption, distribution, metabolism or excretion of another may lead to a pharmacokinetic adverse drug interaction (DN Juurlink et al, JAMA 2003; 289:1652). Additive drug interactions, such as vasodilation caused by both sildenafil (Viagra) and nitrates, can also have adverse effects.

Tinidazole (Tindamax - Presutti Labs), an oral antiprotozoal drug similar to metronidazole (Flagyl, and others), has been approved by the FDA for treatment of trichomoniasis in adults and for treatment of giardiasis, intestinal amebiasis and amebic liver abcess in adults and children more than 3 years old. Tinidazole has been widely used outside of the US for decades under the trade name Fasigyn (Pfizer).

Mild to moderate plaque psoriasis can be treated with topical drugs and phototherapy. Patients with moderate to severe disease generally require systemic therapy. Guidelines for the treatment of psoriasis with topical therapy, phototherapy, and systemic drugs have recently been published.

The FDA has approved Viekira Pak (Abbvie), a fixed-dose combination of two new direct-acting antiviral agents (ombitasvir, paritaprevir) with the pharmacologic enhancer ritonavir in one tablet, co-packaged with a third new direct-acting antiviral agent (dasabuvir) in a second tablet, for oral treatment of chronic hepatitis C virus (HCV) genotype 1 infection. Genotype 1 is responsible for 70-80% of HCV infections in the US.

Telithromycin (Ketek - Aventis) has been approved by the FDA for oral treatment of mild to moderate community-acquired pneumonia, acute exacerbations of chronic bronchitis and acute bacterial sinusitis in patients age 18 and older. The drug is the first in a new class of antibiotics, the ketolides, derived from the macrolide erythromycin. Telithromycin has been marketed in Europe since 2001.

Caspofungin acetate(Cancidas) is the first of a new class of antifungals, the echinocandins. It has been approved by the FDA for treatment of invasive aspergillosis in patients who fail to respond to or are unable to tolerate other antifungal drugs such as amphotericin B and itraconazole.