In September 2015, the US Food and Drug Administration approved adalimumab, the well-known injectable tumor necrosis factor (TNF)–α inhibitor indicated for psoriasis and other inflammatory conditions, for treatment of moderate to severe hidradenitis suppurativa (HS), classifying it as the first and only US Food and Drug Administration–approved therapy for adults with HS.
Pivotal studies (PIONEER/HS-I and -II, phase 3, double-blind) evaluated 633 patients (307 in HS-I and 326 in HS-II) with moderate to severe HS who were randomized to adalimumab versus placebo for 12 weeks. There was significant clinical response (at least 50% reduction in abscess and inflammatory nodule count, defined as hidradenitis suppurativa clinical response, HiSCR) in the adalimumab group (42% vs 26% in HS-I, 59% vs. 28% in HS-II, P<.001), reduction in pain (significant in the HS-II trial, 45.7% vs 20.7%, P<.001; HS-I 27.9% vs 24.8%, P>.05), and no new safety concerns when compared to other adalimumab dosages and indications. Some HS-II study patients (19.3%) were permitted to use oral antibiotics during the study.
For the indication of adult HS (moderate to severe disease), adalimumab should be administered subcutaneously at a dosing regimen of 160 mg/4 syringes on day 1 (or 80 mg/2 syringes on days 1 and 2), followed by 80 mg/2 syringes on day 15, then 40 mg/1 syringe on day 29, and every 7 days thereafter for an indefinite treatment period.
What’s the Issue?
It sits well with dermatologists when the indications for a medication with which we have great familiarity are broadened to include new disease entities; it is even better when the new entity is a condition for which every dermatologist pines for efficacious treatment options. Despite the disease burden of HS, which can include pain, scarring, disfigurement, social exclusion, and/or embarrassment, as well as the wasteful and burdensome effect that HS has on health care resources, such as injudicious use of antibiotics and unnecessary emergency department visits and inpatient hospital stays,1 there is nonetheless a wide-open and inviting playing field for effective therapies.
Although a much higher dosage of adalimumab is required in the treatment of HS compared to what is indicated for psoriasis patients, its safety concerns and side effect profile were unchanged in HS, and therefore its monitoring guidelines remain the same. Not all patients in these studies showed a notable reduction in lesion count, but given that HS classically is unresponsive to most medication regimens, will you embrace this therapy option for your patients with HS?