Long-term safety profile of belimumab plus standard therapy in patients with systemic lupus erythematosus
Arthritis & Rheumatism,
Merrill JT et al. – Belimumab added to standard therapy was generally well–tolerated over 4–year treatment for systemic lupus erythematosus (SLE), suggesting that belimumab can be administered long term with an acceptable safety profile.Methods
- Patients who were randomized to intravenous placebo, or belimumab 1, 4, or 10 mg/kg, plus standard therapy, and completed the 52–week, double–blind period were then allowed to enter a 24–week open–label extension; belimumab patients received either the same dose or were switched to 10 mg/kg, whereas placebo patients were switched to belimumab 10 mg/kg.
- Patients in the 24–week extension (who achieved a satisfactory response) were allowed to participate in the long–term continuation study of monthly belimumab 10 mg.
- Adverse events (AEs) and laboratory abnormalities were analyzed per 100 patient–years in 1–year intervals.
- Of 364 patients completing 52–week double–blind treatment, 345 entered the 24–week extension and 296 continued treatment with belimumab in the long–term continuation study.
- Safety data through 4 years of belimumab exposure (1165 cumulative patient–years) are reported.
- Incidence rates of AEs, severe/serious AEs, infusion reactions, infections, malignancies, grades 3/4 laboratory abnormalities, and discontinuations due to AEs were stable or declined during 4–year belimumab exposure.
- The most common AEs included arthralgia, upper respiratory tract infection, headache, fatigue, and nausea. Serious infusion reactions were rare: only 1 occurred during 4–year follow–up. Serious infection rates decreased from 5.9 to 3.4/100 patient–years and no specific type of infection predominated.