Paradoxical Eczema Risk Low With Biologic Psoriasis Tx

Patients with psoriasis being treated with biologics have a low overall risk for developing the paradoxical symptoms of eczema, with interleukin (IL)-23 inhibitors found to confer the lowest risk of the drug classes examined in a large observational analysis.

Using data from the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR) database, Ali Al-Janabi, MA, from the University of Manchester (England) and associates found that 273 (1%) of approximately 25,000 drug exposures in 13,699 biologic-treated patients with psoriasis were associated with paradoxical eczema.

The incidence of paradoxical eczema was found to vary by class. The highest rate was seen for IL-17 inhibitors, at 1.22 per 100,000 person-years, and the lowest rate was seen with IL-23 inhibitors, at 0.56 per 100,000 person-years. The respective incidence rates for tumor necrosis factor (TNF) inhibitors and IL-12/IL-23 inhibitors were a respective 0.94 and 0.80 per 100,000 person-years.

“Compared with TNF inhibitors, IL-23 inhibitor exposure was associated with significantly lower risk of paradoxical eczema,” the BADBIR Study Group reported in JAMA Dermatology. Indeed, patients treated with IL-23 inhibitors were 61% less likely than were those taking TNF-inhibitors to experience a paradoxical eczema event.

“These findings remained when restricting the analysis to first-line biologic exposures and were specific to this eczema phenotype” the group said.

Cautious Interpretation

As the corresponding author for the work, Mr Al-Janabi observed in an email that the research needs to be replicated, and the findings need to be interpreted with caution.

“As well as usual clinical variables influencing biologic selection, clinicians could consider IL-23 inhibitors in patients with previous atopic dermatitis, hay fever, or paradoxical eczema episodes, as this class was associated with the lowest risk of paradoxical eczema,” he suggested.

A prior history of atopic dermatitis (AD) and hay fever appears to be particularly relevant, as both substantially upped the chances that paradoxical eczema would occur, with hazard ratios of 12.40 and 3.78, respectively. Increasing age also increased the risk, albeit slightly (hazard ratio [HR], 1.02 per year), and there was an apparent lower risk (HR, 0.60) comparing men and women.

The BADBIR Study Group authors believe that, to the best of their knowledge, this is the first study to compare paradoxical eczema risk by biologic class. “Based on clinical experience and prevalence of eczematous reactions reported in some IL-17 inhibitor clinical trials, we suspected an association between IL-17 inhibitor exposure and paradoxical eczema,” they wrote.

“While the incidence of paradoxical eczema was numerically highest among IL-17 inhibitor exposures, it was not significantly different from the incidence among TNF inhibitor exposures.” The low overall incidence of paradoxical eczema “may be reassuring for patients and clinicians,” they added, “but it is possible that the incidence was underestimated due to underreporting or exclusion of adverse events with insufficient detail.”

Details of the Analysis, Other Findings

To explore the risk of paradoxical eczema by biologic class and identify possible risk factors, the BADBIR Study Group performed a prospective cohort study using data held within the BADBIR database between September 2007 and December 2022.

Adults over the age of 18 year or older with plaque psoriasis and who had been treated with at least one of the following biologics were eligible for inclusion: the TNF inhibitors adalimumab, certolizumab pegol, etanercept, and infliximab; the IL-17 inhibitors bimekizumab, brodalumab, ixekizumab, and secukinumab; the IL-12/23 inhibitor ustekinumab; and the IL-23 inhibitors guselkumab, risankizumab, and tildrakizumab.

Patient records and adverse event data were reviewed to determine the incidence of paradoxical eczema events, using terms such as eczema, eczematized, eczematous, atopy, atopic, and dermatitis.

Of 24,952 drug exposures analyzed, the majority (11,819) were for TNF inhibitors, followed by IL-17 inhibitors (4776), IL-12/23 inhibitors (6423), and finally, IL-23 inhibitors (1934).

Mr Al-Janabi and coauthors reported that the median time to onset of paradoxical eczema events was 294 days — approximately 9.8 months. The earliest that these events were recorded was at 120 days (4 months), and the latest at 699 days (almost 2 years).

The face and neck were the most common sites affected (26% of exposures), with other sites including the limbs (23%), the trunk (13%), and hands or feet (12%). Itching (18%), redness (7%), and dryness (4%) were the most commonly reported symptoms.

The researchers noted that 21 patients had skin biopsies taken and “all showed spongiosis or a feature of eczema, with 1 having overlapping features of psoriasis.”

In the majority (92%) of cases, patients experienced only one eczema event. Of the 20 patients who had more than one event, just over one-fifth of repeat events occurred after receiving the same biologic as for the index event. A quarter of events occurred after a different biologic of the same class had been used, and just over half of events occurred after a different class of biologic had been given.

Strengths and Limitations

The “large sample size and inclusion of multiple lines of exposure per participant” are strengths of the study, said the researchers. “We included data for all currently available biologics, originating from more than 160 dermatology centers in the UK and Ireland.”

They added, however, that the “main limitation is the small numbers of observations within certain subgroups, such as specific biologic exposures or participants in ethnic minority groups, restricting generalizability of our findings and the interpretation of some subgroup analyses.”

Moreover, the small number of paradoxical eczema events seen may have resulted in imprecise effect estimates, they observe, noting that the number of exposures to IL-23 inhibitors was low compared with other classes.

“Future studies with more exposures and paradoxical eczema events would enable a more robust analysis of individual drugs and patient subgroups,” the authors concluded.

The study was funded by the Medical Research Council. BADBIR is coordinated by The University of Manchester, and funded by the British Association of Dermatologists (BAD). The BAD receives income from AbbVie, Almirall, Amgen, Celgene, Janssen, LEO Pharma, Lilly, Novartis, Samsung Bioepis, Sandoz Hexal AG, and UCB Pharma for providing pharmacovigilance services. This income finances a separate contract between the BAD and The University of Manchester, which coordinates BADBIR. Mr Al-Janabi reported receiving grants from the Medical Research Council during the conduct of the study; nonfinancial support from UCB, Almirall, and Janssen; and personal fees from UCB outside the submitted work.

This article originally appeared on MDedge.com, a part of the Medscape Professional Network.