VIENNA — The interleukin-1 receptor antagonist (IL-1RA) canakinumab provided control of systemic juvenile idiopathic arthritis (sJIA) without the use of glucocorticoids for up to a year in most study participants after three monthly injections.
In this study of 20 patients with newly diagnosed sJIA treated off glucocorticoids, fever was controlled after a single injection in all patients, and 16 patients reached the primary outcome of remission after three injections, said Gerd Horneff, MD, PhD, Asklepios Children’s Hospital, Sankt Augustin, Germany.
Results of this open-label study, called CANAKINUMAB FIRST, were presented as late-breaking findings at the European Alliance of Associations for Rheumatology (EULAR) 2024 Annual Meeting.
“Steroid-free, first-line treatment with canakinumab led to sustained responses in most patients, with a considerable number achieving remission,” said Dr. Horneff, adding that the observation in this group is ongoing.
Building on Earlier Data
The efficacy of canakinumab was previously reported in anecdotal experiences and one small patient series published 10 years ago. Dr. Horneff noted that he has offered this drug off label to patients with challenging cases.
The objective was to evaluate canakinumab as a first-line monotherapy administered in the absence of glucocorticoids. The study was open to children aged 2-18 years with active sJIA/juvenile Still disease confirmed with published criteria. All were naive to biologic or nonbiologic disease-modifying antirheumatic drugs as well as steroids.
The median age of the children was 8.4 years. A total of 60% were men. The median disease duration at the time of entry was 1.2 months. Most had fever (95%) and rash (80%) with high levels of inflammatory markers at baseline. The mean number of painful joints was 3.1, and the mean number of systemic manifestations was 2.8. No patient was without any systemic involvement, but four of the patients did not have any painful joints.
At enrollment, patients were scheduled to receive three injections of canakinumab at monthly intervals during an active treatment phase, after which they entered an observation phase lasting 40 weeks. In the event of nonresponse or flares in either phase, they were transitioned to usual care.
Symptoms Resolve After Single Injection
After the first injection, active joint disease and all systemic manifestations resolved in 16 (80%) of the 20 patients. Joint activity and systemic manifestations also remained controlled after the second and third injections in 16 of the 20 patients.
One patient in this series achieved inactive disease after a single injection but developed what appeared to be a treatment-related allergic reaction. He received no further treatment and was excluded from the study, although he is being followed separately.
“According to sJADAS [systemic JIA Disease Activity Score] criteria at month 3, 14 had inactive disease, three had minimal disease activity, and one patient had moderate disease activity,” Dr. Horneff said.
At week 24, or 3 months after the last injection, there was still no joint activity in 16 patients. Systemic manifestations remained controlled in 13 patients, but 1 patient by this point had a flare. Another flare occurred after this point, and other patients have not yet completed the 52-week observation period.
“Of the 10 patients who remained in the study and have completed the 52-week observation period, eight have had a drug-free remission,” Dr. Horneff said.