Background/Purpose: Tocilizumab (TCZ) administered intravenously (IV) was shown to improve the signs and symptoms of polyarticular (p)JIA and systemic (s)JIA.^1,2 An ongoing 3-year, long-term extension (LTE) of two 52-week, open-label studies in patients (pts) with pJIA/sJIA will evaluate long-term safety and efficacy of subcutaneous (SC) TCZ; 90-day safety results to the clinical cutoffs December 1, 2017 (pJIA) and February 28, 2018 (sJIA) are reported.

Methods: Pts aged 1-17 years received body weight (BW)–based TCZ SC dosing regimens: pJIA pts received TCZ 162 mg every 3 weeks (Q3W) for BW <30 kg or every 2 weeks (Q2W) for BW ≥30 kg; sJIA pts received TCZ 162 mg Q2W for BW <30 kg (every 10 days until week 14) or weekly (QW) for BW ≥30 kg. pJIA pts had failed MTX treatment or could not tolerate MTX and sJIA pts had inadequate response to NSAIDs and glucocorticoids. All pts had to discontinue biologic DMARDs (except TCZ IV, which was switched to SC). After 52 weeks, eligible pts continued TCZ treatment according to BW in the LTE; we report 90-day safety data for pJIA and sJIA as adverse events (AEs), serious AEs (SAEs), and AEs of special interest (AESIs). The safety populations included all pts who received ≥1 dose of TCZ SC and had ≥1 postdose safety assessment.
Results:   Of pJIA pts (n = 44), 72.7% were female and 88.6% white. Of sJIA pts (n = 38), 55.3% were female and 84.2% white. Median (range) age in both groups was 9.0 (2-18) years. AE rates (Table [image]) were similar regardless of BW. Most AEs were grade 1 or 2; grade ≥3 AEs were reported by 10/44 (20.8%) pJIA pts and 4/38 (10.5%) sJIA pts. The most common AE was nasopharyngitis in both pJIA (17/44 [38.6%]) and sJIA (11/38 [28.9%]). Other AEs reported in ≥15% of pts were arthralgia, gastroenteritis, cough, vomiting, diarrhea, pyrexia, headache, and oropharyngeal pain in pJIA, and upper respiratory tract infection, cough, pyrexia, arthralgia, and rash in sJIA. AESIs were consistent with the 52-week data, and no opportunistic infections developed. Neutropenia AEs were reported by 6 pJIA pts (13.6%) and 7 sJIA pts (18.4%). Of pJIA pts, 5/44 (11.4%) experienced SAEs (furuncle, appendicitis, pneumonia, eye pain/headache, infectious mononucleosis); only pneumonia was considered treatment related. Of sJIA pts, 2/38 (5.3%) experienced SAEs (pneumonia, craniocerebral injury from a fall); neither was considered treatment related. Neutralizing anti-TCZ antibodies developed in 2 pJIA pts (4.7%) and 0 sJIA pts. No deaths were reported in the LTE to the data cutoff.

Conclusion: In this long-term extension study of SC TCZ in children with pJIA or sJIA, TCZ continues to have an acceptable tolerability profile with no new safety concerns. References: 1. Brunner HI et al. Ann Rheum Dis. 2015;74:1110-1117. 2. De Benedetti F et al. N Engl J Med. 2012;367:2385-2395. Acknowledgment: PRINTO and PRCSG Investigators. Medical writing: Sally Mitchell, PhD, funded by F. Hoffmann-La Roche Ltd.