Assessing the Long-Term Safety and Efficacy of Tocilizumab in Systemic Sclerosis

Numeric improvements in modified Rodnan skin scores (mRSS) and forced vital capacity (FVC) in patients with systemic sclerosis (SSc) receiving anti-interleukin-6 (IL-6) receptor-α antibody tocilizumab at 96 weeks were found to be consistent with those of a double-blind period of a previous phase 3 trial, according to study data presented at the American College of Rheumatology (ACR) Convergence 2020, held virtually from November 5 to 9, 2020.

Adult patients with active SSc (disease duration, ≤60 months; mRSS, 10-35) who received placebo or tocilizumab in the double-blind period received 162 mg of tocilizumab weekly from weeks 48 to 96 in the current open-label study. Researchers assessed changes in mRSS and percent predicted FVC (ppFVC) up to week 96, without formal statistical analysis.

Overall, 85 of the 105 participants (81%) who received tocilizumab and 82 of the 107 (77%) who received placebo received open-label tocilizumab and completed the treatment up to week 96.

Changes in ppFVC for participants who were switched from placebo to tocilizumab were comparable between weeks 48 and 96 to changes in those who had received tocilizumab from baseline to week 48 in the double-blind period. There was a continued decline in mRSS for both groups in the open-label period.

Rates of serious adverse events in the open-label period were 15.8 per 100 person-years (PY; 95% CI, 8.6-26.5 per 100 PY) for participants who received tocilizumab and 14.8 per 100 PY (95% CI, 7.9-25.3 per 100 PY) for those who received a placebo and were switched to tocilizumab in the open-label period. Rates of serious infections were 2.3 per 100 PY (95% CI, 0.3-8.1 per 100 PY) and 3.4 per 100 PY (95% CI, 0.7-10.0 per 100 PY), respectively.

“Although [open-label] data have to be interpreted with caution, results from the [open-label tocilizumab] treatment show numeric improvements in mRSS and FVC preservation similar to those of the [double-blind] period, with a beneficial effect on trajectory of FVC decline in patients who switched from [placebo] to [tocilizumab],” the researchers concluded. “Long-term safety results were consistent with the known safety profile of [tocilizumab], and no new or unexpected events were observed.”

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

Khanna D, Lin CJF, Spotswood H, et al. Safety and efficacy of subcutaneous tocilizumab in systemic sclerosis: results from the open-label period of a phase 3 trial. Presented at: ACR Convergence 2020; November 5-9, 2020. Abstract 0396.