No Association Found Between Biologic Use for Hidradenitis Suppurativa, COVID-19 Severity

An analysis of data on patients with hidradenitis suppurativa and COVID-19 found that biologic use was not associated with worse COVID-19 outcomes in this population.

Data gleaned from the Global Hidradenitis Suppurativa COVID-19 Registry revealed biologic therapy was not associated with increased COVID-19 severity in patients with hidradenitis suppurativa (HS). The research was published in the Journal of the American Academy of Dermatology.

HS is a condition that causes small painful lumps to form under the skin, typically in places where skin rubs together such as the armpits or groin, according to the Mayo Clinic. The condition usually occurs after puberty, and lumps heal slowly, can recur, and lead to tunnels under the skin and scarring.

Due to associated comorbidities and biologic treatment, researchers hypothesized that patients with HS may be at a greater risk of severe COVID-19 and poor outcomes.

To better assess this association, investigators looked at data reported between April 5, 2020, and February 2, 2021, among patients with a health care provider (HCP)–confirmed case of HS. A total of 135 eligible self-reported cases of COVID-19 and 44 eligible HCP-reported cases of COVID-19 were included in this analysis.

Throughout the study window, no myocardial infarctions, strokes, or deaths were reported, and “tumor necrosis factor inhibitors were the most commonly used biologic (self-reported: 22/25, 88%; and HCP: 19/22, 86.3%),” authors wrote.

Of those who self-reported COVID-19, no complications occurred in 49.3% of patients and 64.9% required no COVID-19 treatment.

Analyses revealed:

  • Among the self-reported cases, the odds of hospitalization (biologic: 3/25 [12%]; nonbiologic: 19/110 [17.4%]; odds ratio [OR], 0.34, P = .16) or oxygen requirement (biologic: 5/25 [20%]; nonbiologic: 28/110 [25.5%]; OR, 0.6, P = .37) were not greater with biologics.
  • Patients on biologic therapy reported longer time to COVID-19 resolution (biologic: median [interquartile range], 21 [14-31] days; nonbiologic: 14 [9-25] days; P = .07).
  • Among the HCP-reported cases, 78.1% (32/44) had mild COVID-19, and no differences in severity were seen between those on biologics vs those on nonbiologics (P = .2) and between those who continued biologics vs those who discontinued biologics (P = .9).
  • No complications were experienced by 86.4% (38/44) of the patients, and 84.1% (37/44) required no COVID-19 treatment.

The study was not sufficiently powered to assess differences in COVID-19 severity based on age or comorbidities in either group.

Previous research conducted in the US population with HS found that 8 of 39 patients with COVID-19 were hospitalized and 1 not taking systemic treatments for HS died. In this analysis, “male sex, antibiotic treatment, diabetes, and increased mean age were associated with hospitalization. One patient on infliximab had a mild COVID-19 course and did not require hospitalization,” authors wrote.

A relatively small sample size, the possibility of missed cases, and potential for recall bias mark limitations to the current analysis. However, the study is the largest to date on COVID-19 outcomes in an international population with HS.

“These data provide valuable information to guide patient care during and after the pandemic,” researchers concluded.


Naik HB, Alhusayen R, Frew J, et al. Biologic therapy is not associated with increased COVID-19 severity in patients with hidradenitis suppurativa: initial findings from the global hidradenitis suppurativa COVID-19 registry. J Am Acad Dermatol. Published online September 15, 2021. doi:10.1016/j.jaad.2021.09.016