Researchers investigated belimumab's (Benlysta®) effect on low platelet (thrombocytopenia) and low white blood cell (leukopenia) counts in people with systemic lupus erythematosus (SLE) and found the therapy helps improve lupus-related thrombocytopenia. People with lupus are more likely to develop thrombocytopenia because their immune system mistakenly attacks and destroys healthy platelets. 

Investigators conducted a post hoc analysis (a review of existing data from studies originally designed to answer a different question) of data from five large belimumab trials in people with active non-renal SLE.  The data group included 1,769 people treated with belimumab and 1,144 on placebo, in addition to standard therapy. Among the belimumab‑treated group, 39 had thrombocytopenia and 346 had leucopenia, compared with 25 and 203 in the placebo group. They found that thrombocytopenia was resolved earlier and in more belimumab-treated people (p=0.0267), with one-third achieving sustained improvement through week 52 versus 8% on placebo. A clear advantage of belimumab over placebo was evident by week 12. Leukopenia improved slowly, but with no significant treatment difference. 

These findings suggest, for the first time, that belimumab may have benefits in treating blood-related symptoms of SLE. Continue to follow the Lupus Foundation of America for updates on lupus treatments. Learn more about Benlysta and lupus thrombocytopenia.  

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