Severe Immediate and Delayed Hypersensitivity Reactions to Biologics in a Toddler With Systemic Juvenile Idiopathic Arthritis

Efficacy and safety of therapies for Still's disease and macrophage activation syndrome (MAS): a systematic review informing the EULAR/PReS guidelines for the management of Still's disease

OBJECTIVES

To analyse the efficacy and safety of treatments for Still's disease and macrophage activation syndrome (MAS).

METHODS

Medline, Embase and Cochrane Library were searched for clinical trials (randomised, randomised controlled trial (RCT), controlled and clinical controlled trial (CCT)), observational studies (retrospective, longitudinal observational retrospective (LOR), prospective and longitudinal observational prospective (LOP)) and systematic reviews (SRs), in which the populations studied were patients with Still's disease and MAS. The intervention was any pharmacological treatment (approved or under evaluation) versus any comparator drug or placebo, and as outcomes, any relevant efficacy and safety event. The risk of bias (RoB) was assessed with the Cochrane RoB and AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews-2, version 2) for SRs.

RESULTS

128 full texts were included: 25 RCTs, 1 CCT, 11 SRs published after 2013 and 91 LOP/LOR studies. In Still's disease, interleukin (IL)-1 inhibitors (IL-1i) and IL-6R inhibitors (IL-6i) were the most studied drugs. Two meta-analyses on RCTs showed an OR, to achieve an ARC50 response rate, of 6.02 (95% CI 2.24 to 21.36) and 8.08 (95% CI 1.89 to 34.57) for IL-1i and IL-6Ri, respectively. Retrospective studies showed that early initiation of IL-1i or IL-6i was associated with high rates of clinically inactive disease. In MAS, GCs were employed in all patients, often associated with ciclosporin and/or anakinra. Rates of complete response were reported, with a range from 53% to 100%. Emapalumab was the only drug tested in a CCT, with a complete response of 93%.

CONCLUSION

IL-1i and IL-6Ri show the highest level of efficacy in the treatment of Still's disease. For MAS, IL-1 and interferon-γ inhibition appear to be effective on a background of high-dose glucocorticoids.

Adverse events of biological agents in pediatric rheumatologic diseases

OBJECTIVES

To evaluate adverse events (AEs) in pediatric patients with rheumatologic diseases being treated with approved or off-label biologic agents (BAs).

METHODS

This observational, retrospective, multicenter study was conducted from 2010 to 2022 in patients under 18 years of age with rheumatic diseases who were receiving interleukin-1 antibodies (Anti-IL1), interleukin-6 antibodies (Anti-IL6), and tumor necrosis factor alpha inhibitors (anti-TNF). Efficacy, AEs, and timing of AEs were collected from electronic medical records.

RESULTS

Three hundred and fifteen BAs were prescribed to 237 patients. Fifty AEs occurred in 44 patients (18.6%). Anti-TNF exposure was present in 8 (72.2%) of 11 patients with latent tuberculosis (TB) and in all 7 patients with herpes infections. Four of 6 patients (66.7%) with recurrent upper respiratory tract infections and 7 of 8 patients (87.5%) with local skin reactions were on Anti-IL1. The cutoff value for latent TB development was determined as 23.5 months by ROC analysis (AUC: 0.684 ± 0.072, p = 0.038, 95% CI: 0.54-0.82). In patients who used BA for 23.5 months or more, the risk of latent TB was 5.94-fold (p = 0.024, 95% CI: 1.26-27.97). Drug rash with eosinophilia and systemic symptoms (DRESS) occurred in 2 patients on anakinra, and anaphylaxis occurred in 1 patient on anti-IL6. There were no cases of malignancy or death in any patient.

CONCLUSION

The physician should be vigilant for latent TB in patients exposed to BA for more than 2 years. While local skin reactions are more prevalent in patients receiving anti-IL1, severe skin reactions such as DRESS may also occur.