Trial results for a Phase 3 study (NCT03000439) investigating tofacitinib in pediatric patients with systemic juvenile idiopathic arthritis (sJIA) were posted on ClinicalTrials.gov on 2025-06-03. The study evaluated the time to sJIA flare, reporting a median time of 295.0 days for the placebo group, while the median for the tofacitinib group was not reached. The unstratified log-rank test for the hazard ratio was 0.633 (95.0% CI: 0.296 to 1.354) with a p-value of 0.1171.
Background
The study, titled "A Safety, Efficacy And Pharmacokinetics Study Of Tofacitinib In Pediatric Patients With sJIA," aimed to assess tofacitinib in pediatric patients diagnosed with Systemic Juvenile Idiopathic Arthritis (sJIA).
Trial design
The Phase 3 study (NCT03000439) was a randomized withdrawal trial enrolling 100 participants with Arthritis Juvenile Idiopathic (sJIA). Responders to an open-label treatment phase with tofacitinib were randomized in a 1:1 ratio to either tofacitinib or placebo in a double-blind phase. The primary endpoint evaluated was "time to sJIA flare," with subjects discontinued upon experiencing a flare. An interim analysis for efficacy and futility was planned when at least 20 flares were observed.
Key results
For the primary outcome of "Time to Systemic Juvenile Idiopathic Arthritis (sJIA) Disease Flare: Double-Blind Phase":
- The median time to sJIA disease flare for the Placebo DB group was 295.0 Days.
- The median time to sJIA disease flare for the Tofacitinib 5mg BID DB group was NA (not reached).
An unstratified log-rank test for the hazard ratio yielded a value of 0.633 (95.0% Confidence Interval: 0.296 to 1.354) with a p-value of 0.1171.
Regarding the "Probability of Occurrence of sJIA Disease Flare at DB Weeks 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44, 48 and 52: Double-Blind Phase":
- At DB Week 4, the probability of flare was 7.1 Percentage probability of occurrence for Tofacitinib 5mg BID DB and 6.5 Percentage probability of occurrence for Placebo DB. The difference was 0.7 (95.0% CI: -12.2 to 13.6).
- At DB Week 8, the probability of flare was 14.3 Percentage probability of occurrence for Tofacitinib 5mg BID DB and 22.6 Percentage probability of occurrence for Placebo DB. The difference was -8.3 (95.0% CI: -27.9 to 11.3).
- At DB Week 12, the probability of flare was 21.4 Percentage probability of occurrence for Tofacitinib 5mg BID DB and 32.3 Percentage probability of occurrence for Placebo DB. The difference was -10.8 (95.0% CI: -33.2 to 11.6).
- At DB Week 16, the probability of flare was 25.0 Percentage probability of occurrence for Tofacitinib 5mg BID DB and 38.7 Percentage probability of occurrence for Placebo DB. The difference was -13.7 (95.0% CI: -37.2 to 9.8).
- At DB Week 20, the probability of flare was 32.1 Percentage probability of occurrence for Tofacitinib 5mg BID DB and 45.4 Percentage probability of occurrence for Placebo DB. The difference was -13.2 (95.0% CI: -37.9 to 11.5).
What this means
The trial results indicate that tofacitinib may prolong the time to sJIA flare in pediatric patients, as the median time to flare was not reached in the tofacitinib group compared to 295.0 days in the placebo group. However, the statistical analysis using the unstratified log-rank test for the hazard ratio did not demonstrate a statistically significant difference (p-value of 0.1171). While the probability of flare was generally lower in the tofacitinib group at later time points, the confidence intervals for the differences in percentage probability of flare at various weeks crossed zero, suggesting no statistically significant advantage for tofacitinib over placebo based on these specific analyses.
Source
The information regarding these trial results was obtained from ClinicalTrials.gov, a public database of clinical studies. The results for study NCT03000439, titled "A Safety, Efficacy And Pharmacokinetics Study Of Tofacitinib In Pediatric Patients With sJIA," were posted on 2025-06-03 on clinicaltrials.gov.