Malignancy and infection risk during adalimumab therapy in hidradenitis suppurativa

The association of adalimumab therapy with malignancy and infection is established in other inflammatory diseases; however, rates of hidradenitis suppurativa (HS) are based on case reports or retrospective healthcare data and the effect of adalimumab therapy on these rates is unknown. Previously reported rates in the PIONEER OLE Phase 3 study reported on rates only in a subpopulation of 88 participants rather than the entire cohort.

To quantify rates of malignancy and serious infection in all patients with HS treated with adalimumab 40 mg weekly.

Reanalysis was undertaken of individual patient data from the PIONEER 1, PIONEER 2 and PIONEER open-label extension Phase 3 trial data encompassing 591 unique patients with HS administered adalimumab 40 mg weekly without concurrent antibiotic exposure. Incidence rates of serious infection and malignancy were calculated.

Incidence rates of serious infection and malignancy were 2.14 and 0.46 per 100 patient-years, respectively. Rates of infection and malignancy were comparable to those in other inflammatory conditions examined.

Incidence of serious infection in patients with HS on adalimumab is comparable to those with psoriasis and inflammatory arthropathies, but the incidence of malignancy is increased. This may reflect disease-specific malignancy risk rather than an effect of adalimumab.