Study Reports Safety Data in Children on JAK Inhibitors

TOPLINE:
Reports of blood and lymphatic disorders were higher in pediatric patients treated with Janus kinase (JAK) inhibitors than in adults in a review of US and Canadian adverse event (AE) data, which also found that acne was the most common skin-related AE in children, and serious AEs were less common.
METHODOLOGY:
Researchers analyzed 399,649 AEs in 133,216 adult patients and 2883 AEs in 955 pediatric patients (age, < 18 years) from November 2011 to February 2023 using the US Food and Drug Administration Adverse Event Reporting System and the Canada Vigilance Adverse Reaction Online Database.
AEs were categorized on the basis of the Medical Dictionary for Regulatory Activities system organ class.
Five JAK inhibitors approved for use in children were included in the study: Baricitinib, upadacitinib, abrocitinib, ruxolitinib, and tofacitinib.
TAKEAWAY:
The most frequently reported AEs in children were blood and lymphatic system disorders, including neutropenia, thrombocytopenia, and anemia (24%); viral, fungal, and bacterial infections, such as pneumonia and sepsis (17.2%); constitutional symptoms and administrative concerns, including pyrexia and fatigue (15.7%); gastrointestinal disorders, such as vomiting and abdominal pain (13.6%); and respiratory disorders, such as cough and respiratory distress (5.3%).
In adults, the most common AEs were viral, fungal, and bacterial infections (16.8%); constitutional symptoms and administrative concerns (13.5%); musculoskeletal and connective tissue disorders (7.04%); and gastrointestinal (5.8%) and nervous system (5%) disorders.
Acne (30.6%), atopic dermatitis (22.2%), and psoriasis (16.7%) were the most common skin and subcutaneous tissue AEs reported in children. Skin and subcutaneous AEs were more common with upadacitinib (21.1%), abrocitinib (9.1%), and tofacitinib (6.3%) in children.
Serious AEs included in the boxed warning for JAK inhibitors — serious infection, mortality, malignancy, cardiovascular events, and thrombosis — were similar for baricitinib in children (4 of 49 patients, 8.2%) and adults (325 of 3707, 8.8%). For other JAK inhibitors, absolute numbers of these AEs in children were small and rates were lower in children than in adults.
IN PRACTICE:
“This information can support customized treatment and minimize the potential for undesired or intolerable AEs,” the authors wrote.
SOURCE:
This study was led by Sahithi Talasila, BS, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, and was published online on September 5 in Pediatric Dermatology.
LIMITATIONS:
Pharmacovigilance registries did not fully capture the complete range of AEs because of potential reporting bias or recall bias. Additionally, events lacking sufficient objective evidence were underreported, while common AEs associated with JAK inhibitor therapy were overreported.
DISCLOSURES:
No specific funding sources for the study were reported. One author reported being a consultant, one reported serving as a principal investigator in clinical trials, and another reported serving on data and safety monitoring boards of various pharmaceutical companies.
This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.
 
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