Off-label treatment with biologics effective for treating certain skin diseases

Key Points

"Pemphigus vulgaris with rituximab (Rituxan, Genentech) has been a major advance, although this is not a formally approved indication for the drug," says Alan Menter, M.D., chief, dermatology, and chairman, residency program, Baylor University Medical Center, Dallas. "However, pemphigus vulgaris is a relatively rare condition and rituximab certainly has other indications."

Conventional treatment for pemphigus vulgaris, an autoimmune blistering disorder affecting the skin and mucous membranes, is systemic steroids and immunosuppressive agents such as methotrexate, azathioprine and cyclosporine, Dr. Menter says.

Rituximab studies

A recent review paper in Expert Review of Clinical Immunology examined data on 153 patients placed on rituximab for pemphigus vulgaris. They noted the mechanism of action is B-cell modulation and that its use has increased clinical remission rates to 65 from 30 percent with traditional therapies.

The authors recommended that rituximab be used to treat patients with pemphigus vulgaris if they fail to respond to conventional therapy or develop serious adverse events due to conventional therapy. They advised that the possibility of extended B-cell depletion supports monitoring of patients for peripheral B-cell counts (Feldman RJ, Ahmed AR. Expert Rev Clin Immunol. 2011;7(4):529-541).

Pemphigus vulgaris has also been treated with a combination of two medications that are both not indicated for the condition: rituximab and intravenous immunoglobulin (IVIG). In one small study, patients were treated first with rituximab followed by IVIG. Investigators found nine of 11 patients had accelerated resolution of lesions and clinical remission, which lasted a mean 31.1 months (Ahmed AR, Spigelman Z, Cavacini LA, Posner MR. N Engl J Med. 2006;355(17):1772-1779).