Belimumab with standard care reduces organ damage in lupus
Patients with systemic lupus erythematosus treated with belimumab, plus the standard of care, demonstrated significantly less organ damage progression compared with those who received the standard of care alone, according to findings published in the Annals of the Rheumatic Diseases.
“Two long-term extension studies have previously demonstrated that long-term exposure to belimumab was safe and well tolerated, with low rates of organ damage accrual over time,” Murray B. Urowitz, MD, of the Toronto Western Hospital, told Healio Rheumatology. “As the long-term extension studies did not have comparator arms, comparison of belimumab plus standard of care with standard of care alone was not possible.”
To extend the work of the long-term extension studies — and enable a long-term comparison of belimumab (Benlysta, GlaxoSmithKline) to standard of care — Urowitz and colleagues used propensity score matching to match patients with SLE treated with belimumab in the U.S. BLISS long-term extension study with patients from an external SLE cohort, called the Toronto Lupus Cohort, who were treated with standard of care.
The researchers conducted a systematic literature review to identify 17 known predictors for organ damage, allowing them to calculate a propensity score for each participant. Each patient from the BLISS extension and the Toronto Lupus Cohort were then matched 1-to-1 based on these propensity scores. The primary endpoint was the difference in change in Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) score from baseline to 5 years.
For this 5-year analysis, Urowitz and colleagues matched 99 participants from each cohort, out of a total of 567 patients. To evaluate the time to organ damage progression, in a follow-up of 1 year or more, the researchers’ sample included 259 patients from the BLISS extension and 706 from the Toronto cohort, of whom 179 from each were matched using propensity scores.
According to the researchers, changes in SDI score were significantly lower among patients treated with belimumab compared with standard of care at year 5 (0.434; 95% CI, –0.667 to –0.201). Regarding time to organ damage progression, patients treated with belimumab were 61% less likely to progress to a higher SDI score during any given year compared with those who received standard of care only (HR = 0.391; 95% CI, 0.253-0.605). Further, the proportion of SDI score increases equaling 2 or more were greater in the standard-of-care group compared with the belimumab group.
“The results of this study demonstrate that belimumab plus standard of care treatment results in lower rates of organ damage accrual compared with standard of care alone,” Urowitz said. “The benefits were demonstrated over a 5-year period.” – by Jason Laday
Disclosure: Urowitz reports research grants from GlaxoSmithKline. Please see the study for all other authors’ relevant financial disclosures.