Effectiveness of Belimumab Treatment in a Subpopulation of Systemic Lupus Erythematosus (SLE) Patients: a Pooled Analysis of BLISS-52 and BLISS-76

• Belimumab 1 mg/kg (Drug): Subjects received belimumab 1 mg/kg in addition to their ongoing stable systemic lupus erythematosus (SLE) treatment regimen. Belimumab was administered intravenously at 0, 2, 4 weeks and every 4 weeks thereafter. The ongoing SLE treatment regimen was to have been stable for at least 30 days prior to Day 0, which consisted of any of the following (alone or in combination): prednisone or equivalent (from 0 to 40 mg/day when used in combination with other SLE treatment or from 7.5 to 40 mg/day alone), anti-malarials, non-steroidal anti inflammatory drugs (NSAIDs), or any immunosuppressive therapy (ie, methotrexate, azathioprine, leflunomide, or mycophenolate calcineurin inhibitors, sirolimus, oral cyclophosphamide, 6-mercaptopurine, or thalidomide).
• Belimumab 10 mg/kg (Drug): Subjects received belimumab 10 mg/kg in addition to their ongoing stable SLE treatment regimen. Belimumab was administered intravenously at 0, 2, 4 weeks and every 4 weeks thereafter. The ongoing SLE treatment regimen was to have been stable for at least 30 days prior to Day 0, which consisted of any of the following (alone or in combination): prednisone or equivalent (from 0 to 40 mg/day when used in combination with other SLE treatment or from 7.5 to 40 mg/day alone), anti-malarials, NSAIDs, or any immunosuppressive therapy (ie, methotrexate, azathioprine, leflunomide, or mycophenolate calcineurin inhibitors, sirolimus, oral cyclophosphamide, 6-mercaptopurine, or thalidomide).
• Placebo (Drug): Subjects received placebo in addition to their ongoing stable SLE treatment regimen. Placebo was administered intravenously at 0, 2, 4 weeks and every 4 weeks thereafter. The ongoing SLE treatment regimen was to have been stable for at least 30 days prior to Day 0, which consisted of any of the following (alone or in combination): prednisone or equivalent (from 0 to 40 mg/day when used in combination with other SLE treatment or from 7.5 to 40 mg/day alone), anti-malarials, NSAIDs, or any immunosuppressive therapy (ie, methotrexate, azathioprine, leflunomide, or mycophenolate calcineurin inhibitors, sirolimus, oral cyclophosphamide, 6-mercaptopurine, or thalidomide).

Primary outcomes

• Responder Rate [Week 52]: Response is defined as: ≥4 point reduction from baseline in SELENA SLEDAI score, no worsening (increase of < 0.30 points from baseline) in PGA, and no new BILAG A organ domain score or 2 new BILAG B organ domain scores.

Secondary outcomes

• SELENA SLEDAI [Week 52]: Percent of subjects with ≥ 4 point reduction from baseline in SELENA SLEDAI score at Week 52
• SF-36 [Week 24]: Mean change in SF-36 Health Survey physical component summary score (PCS) at Week 24
• Time to first flare by SLE Flare Index [Up to Week 52]: Time to 1st SLE flare after 24 weeks by modified SLE Flare Index

Sex: All, ages: 18 Years to any

Inclusion Criteria

* Eligible subjects for BLISS-52 and BLISS-76 included:
* clinical diagnosis of systemic lupus erythematosus (SLE) according to the American College of Rheumatology (ACR) criteria
* "active" (systemic lupus erythematosus) SLE disease, defined as a safety of oestrogen in lupus national assessment (SELENA) systemic lupus erythematosus disease activity index (SLEDAI) disease activity score of at least 6 at screening
* an unequivocally positive antinuclear antibodies (ANA) test result, from 2 independent time points within the study screening period or 1 positive historical test result and 1 positive test result during the screening period. ANA test results obtained in the screening period were only considered positive if the ANA titer ≥ 1:80 and/or anti-dsDNA serum antibody was ≥ 30 IU/mL
* on a stable SLE treatment regimen for at least 30 days prior to Day 0, which consisted of any of the following (alone or in combination): prednisone or equivalent (from 0 to 40 mg/day when used in combination with other SLE treatment or from 7.5 to 40 mg/day alone), anti-malarials, non-steroidal anti inflammatory drugs (NSAIDs), or any immunosuppressive therapy (i.e., methotrexate, azathioprine, leflunomide, or mycophenolate calcineurin inhibitors, sirolimus, oral cyclophosphamide, 6-mercaptopurine, or thalidomide).
* Additional inclusion criteria for the purpose of this analysis: subpopulation of patients from the pooled modified Intent-to-Treat population from BLISS-52 and BLISS-76 who have renal, neurological, haematological, or cardiovascular/respiratory organ domain involvement (as defined by a BILAG domain score of A, B or C in at least one of the domains) at baseline and 1 of the following:

  * are anti-dsDNA positive (≥ 30 IU/mL) at baseline, OR
  * have low C3 and/or C4 complement relative to the normal range at baseline.

Exclusion Criteria:

* Key exclusion criteria for BLISS-52 and BLISS-76 included:
* severe active lupus nephritis or Central Nervous System (CNS) lupus
* pregnancy
* receipt of any B cell target therapy at any time
* receipt of an investigational agent within 60 days prior to Day 0 for non-biologics and within 1 year for biologics
* receipt of abatacept (within 1 year), intravenous (IV) cyclophosphamide (within 6 months), anti-tumor necrosis factor (anti-TNF) therapy, anakinra, IV immunoglobulin (IVIG), prednisone > 100 mg/day, or plasmapheresis within 3 months, or live vaccine within 1 month.

• GSK Clinical Trials, Study director, GlaxoSmithKline