Long-term adalimumab efficacy in patients with moderate-to-severe hidradenitis suppurativa/acne inversa: 3-year results of a phase 3 open-label extension study

Background: The optimal long-term dosing strategy for adalimumab (ADA) in hidradenitis suppurativa/acne inversa (HS) was evaluated by pooling the results of the PIONEER phase 3 trials and an open-label extension (OLE) study. Objective: To assess the response to and tolerability of long-term administration of ADA in HS. Methods: The durations of the PIONEER I/II periods A, B, and OLE were 12, 24, and 52 or more weeks, respectively. Patients who entered the OLE and received ADA (40 mg every week continuously) and responders plus partial responders (PRRs) were evaluated. Primary efficacy assessments included measurement of HS clinical response (HiSCR), lesion counts, skin pain, and Dermatology Life Quality Index (DLQI). Treatment-emergent adverse events were assessed. Results: At week 12, 52.3% of those receiving ADA weekly and 73.0% of PRRs achieved HiSCR. Achievement of HiSCR was maintained through week 168 in 52.3% of patients who received ADA weekly and 57.1% of PRRs. Sustained improvement in lesion counts, skin pain, and DLQI score were also observed. The safety profile throughout the OLE was similar to the profiles observed in the PIONEER studies. Limitations: The OLE was uncontrolled. Conclusion: Continuous weekly dosing with ADA, 40 mg, is a reasonable treatment option for long-term control of moderate-to-severe HS.