Table 3.
Changes in biomarker measures from baseline at week 24
| Biomarker | Placebo-to-belimumab 200 mg SC (n = 206) | Belimumab 200 mg SC (n = 456) |
|---|---|---|
| Serological measures | ||
| Anti-dsDNA antibody level | ||
| Positivea at baseline, n | 121 | 326 |
| Shift from positivea to negative, n (%) | 16 (13.2) | 70 (21.5) |
| Negative at baseline, n | 77 | 122 |
| Shift from negative to positivea, n (%) | 2 (2.6) | 4 (3.3) |
| C3 | ||
| Lowb at baseline, n | 88 | 198 |
| Lowb to normal/highc, n (%) | 31 (35.2) | 95 (48.0) |
| Normal/highc at baseline, n | 110 | 250 |
| Normal/highc to lowb, n (%) | 12 (10.9) | 19 (7.6) |
| C4 | ||
| Lowd at baseline, n | 43 | 117 |
| Lowd to normal/highe n (%) | 23 (53.5) | 64 (54.7) |
| Normal/highe at baseline, n | 155 | 331 |
| Normal/highe to lowd n (%) | 4 (2.6) | 13 (3.9) |
| B cell subsets f | ||
| CD19+, n | 194 | 443 |
| Median % change (25th and 75th percentile) | −25.3 (−57.5, 18.0) | −64.6 (−79.4, −40.3) |
| CD20+, n | 192 | 421 |
| Median % change (25th and 75th percentile) | −26.4 (−57.9, 22.6) | −64.5 (−79.8, −38.9) |
| Naïve CD19+CD20+CD27-, n | 192 | 421 |
| Median % change (25th and 75th percentile) | −47.4 (−69.2, −11.0) | −76.0 (−86.6, −58.4) |
| Activated CD19+CD20+CD69+, n | 178 | 406 |
| Median % change (25th and 75th percentile) | −52.3 (−87.5, 10.3) | −73.3 (−93.7, −26.8) |
| Memory CD19+CD20+CD27+, n | 192 | 421 |
| Median % change (25th and 75th percentile) | 82.0 (33.3, 197.2) | 0.0 (−42.3, 57.1) |
| Plasmacytoid CD19+CD20+CD138+, n | 166 | 393 |
| Median % change (25th and 75th percentile) | −22.2 (−79.9, 88.5) | −67.5 (−93.4, 8.3) |
| Plasma CD19+CD20-CD138+, n | 184 | 412 |
| Median % change (25th and 75th percentile) | −54.3 (−86.1, 71.5) | −74.3 (−92.7, −17.7) |
| SLE subset CD19+CD38b+CD27b+Lymph, n | 192 | 422 |
| Median % change (25th and 75th percentile) | −43.8 (−68.4, 9.5) | −64.3 (−83.4, −24.0) |
| Transitional CD19+CD24b+CD38b+CD27-, n | 186 | 412 |
| Median % change (25th and 75th percentile) | −65.1 (−84.4, 0.5) | −63.8 (−84.1, −0.8) |
a
≥ 30 IU/mL.
b
< 90 mg/dL.
c
≥ 90 mg/dL.
d
< 10 mg/dL.
e
≥ 10 mg/dL.
f
Patients with a baseline score of 0 were excluded from the analysis.
Anti-dsDNA: antidouble-stranded DNA; C3: complement 3; C4: complement 4; SC: subcutaneous; SLE: systemic lupus erythematosus.