Biologic therapies with anti–tumor necrosis factor agents are promising treatments for hidradenitis suppurativa (HS).

We assessed the efficacy and safety of infliximab (IFX) for the treatment of moderate to severe HS.

A prospective double-blind treatment phase of 8 weeks where patients received IFX or placebo was followed by an open-label phase where patients taking placebo were given the opportunity to cross over to IFX, and an observational phase. Primary treatment efficacy was based on HS Severity Index. Secondary end points included Dermatology Life Quality Index, visual analog scale, and Physician Global Assessment scores. Inflammatory markers erythrocyte sedimentation rate and C-reactive protein were also assessed.

More patients in the IFX than in the placebo group showed a 50% or greater decrease from baseline HS Severity Index score. In addition, statistically and clinically significant improvement from baseline was observed at week 8 in Dermatology Life Quality Index score, visual analog scale score, erythrocyte sedimentation rate, and C-reactive protein compared with placebo. Patients in the placebo group treated with IFX after week 8 (crossover) responded similarly to the original IFX group. Many patients withdrew during the observational phase to continue anti–tumor necrosis factor-alfa therapy. No unexpected serious adverse events were observed.

Results are representative of a single center, patients were treated by a single physician, some patients did not return after their last infusion, and the HS Severity Index requires validation.

This clinical study represents the first formal assessment of IFX for treatment of moderate to severe HS. IFX was well tolerated, no unexpected safety issues were identified, and improvements in pain intensity, disease severity, and quality of life were demonstrated with concomitant reduction in clinical markers of inflammation.