TNF blocker promising for hidradenitis suppurativa treatment

Key Points

Miami - The first randomized, controlled study to assess the treatment of hidradenitis suppurativa (HS) with a biologic drug shows that infliximab can safely improve disease severity, pain and quality of life.

"We're beginning to understand that HS is a closet disease. Many people have it, but it's under-recognized, undertreated and difficult to manage," says Francisco A. Kerdel, M.D., a dermatologist in private practice at Florida Academic Dermatology in Miami.

Treating HS often proves frustrating, he says, adding that "we recommend weight loss, hygiene, reduction of friction, cessation of smoking and topical and systemic antibiotics. In Europe, often these patients are treated with the combination of clindamycin and rifampicin. Sometimes patients do quite well."

"The more I think about it, the more I believe that if I could identify the patient who is going to develop severe HS, maybe destroying that hair follicle with a hair removal laser could work prophylactically," Dr. Kerdel says. "However, more research in this area needs to be done.

"We have some experience with anti-TNF agents," he says. "Etanercept has not proven to be efficacious in this area, maybe because it has no effect on the granulomatous component. But both infliximab and adalimumab have shown efficacy in small case series."

TNF study

In the only published prospective, double-blinded, placebo-controlled trial of a biologic drug in HS, Dr. Kerdel and his co-authors addressed the efficacy and safety of infliximab in patients with moderate-to-severe HS.

"The vast majority of patients had very severe HS," he says. Investigators randomized 15 patients to receive 5 mg/kg infliximab at weeks zero, two and six; placebo-treated patients (23) crossed over to active treatment at week eight.

After induction therapy, all patients received maintenance treatment every eight weeks until week 22 in the study. During the placebo phase, five patients withdrew from this group.

At week eight, 60 percent of infliximab-treated patients experienced a 25 to 49 percent decrease from baseline in hidradenitis suppurativa severity index (HSSI) scores.

Conversely, 90 percent of placebo-treated patients showed a less than 25 percent decrease in HSSI (P<0.001; Grant A, Gonzalez T, Montgomery MO, Cardenas V, Kerdel FA. J Am Acad Dermatol. 2010;62(2):205-217). Developed by Dr. Kerdel and his colleagues, the HSSI is a 19-point scale that measures parameters such as lesion counts, body surface area affected, drainage and pain.

Also at week eight, 26.7 percent of infliximab-treated patients achieved a 50 percent or greater reduction in HSSI scores, versus 5 percent in the placebo group (P = 0.092).

More significant were patient-assessed pain reductions achieved by infliximab at week eight, says Dr. Kerdel. Measured with a visual analogue scale, these scores fell approximately 75 percent in the treatment group, versus virtually no change in the placebo group.

Patients who switched from the placebo group to active treatment experienced similar results, he says. Very few serious adverse events occurred throughout the trial, Dr. Kerdel says.

Only five patients continued in the trial through its entire 52 weeks - most elected to continue infliximab infusions outside the study shortly after study infusions stopped, Dr. Kerdel says.

"Some patients continued to do well after infusions stopped, but the vast majority need to continue treatment" to avoid relapses, he explains.

Overall, "This trial showed that infliximab is efficacious for HS," Dr. Kerdel says. "Clinical markers for inflammation improved, and there were no unexpected safety issues. In conclusion, the anti-TNF agents open the possibility of using anti-inflammatory agents to manage this chronic problem."

Disclosures: The infliximab study was sponsored by Centocor.