Long-term safety profile of belimumab plus standard therapy in patients with systemic lupus erythematosus

Arthritis Rheum. 2012 Oct;64(10):3364-73. doi: 10.1002/art.34564.


Objective: To evaluate the safety profile of long-term belimumab therapy combined with standard therapy for systemic lupus erythematosus (SLE) in patients with active disease.

Methods: Patients who were randomized to receive intravenous placebo or belimumab 1, 4, or 10 mg/kg, plus standard therapy, and completed the initial 52-week double-blind treatment period were then allowed to enter a 24-week open-label extension phase. During the extension period, patients in the belimumab group either received the same dose or were switched to 10 mg/kg and patients in the placebo group were switched to belimumab 10 mg/kg. Patients who achieved a satisfactory response during the 24-week extension period were allowed to participate in the long-term continuation study of monthly belimumab 10 mg/kg. Adverse events (AEs) and abnormal laboratory results were analyzed per 100 patient-years in 1-year intervals.

Results: Of the 364 patients who completed the 52-week double-blind treatment period, 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 (1,165 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 the 4-year followup period. Rates of serious infection decreased from 5.9/100 patient-years to 3.4/100 patient-years, and no specific type of infection predominated.

Conclusion: Belimumab added to standard therapy was generally well-tolerated over the 4-year treatment period in patients with SLE, which suggests that belimumab can be administered long term with an acceptable safety profile.

Trial registration: ClinicalTrials.gov NCT00071487 NCT00583362.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adrenal Cortex Hormones / therapeutic use
  • Adult
  • Antibodies, Monoclonal / adverse effects*
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Humanized
  • Double-Blind Method
  • Drug Therapy, Combination
  • Female
  • Humans
  • Immunosuppressive Agents / adverse effects*
  • Immunosuppressive Agents / therapeutic use
  • Lupus Erythematosus, Systemic / drug therapy*
  • Male
  • Middle Aged
  • Treatment Outcome


  • Adrenal Cortex Hormones
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • Immunosuppressive Agents
  • belimumab

Associated data

  • ClinicalTrials.gov/NCT00071487
  • ClinicalTrials.gov/NCT00583362