Prescribing patterns in the 6 months before and after initiation of belimumab treatment*
| 6 months before belimumab initiation | 6 months after belimumab initiation | P value, pre versus post | |||
| n=1710 | |||||
| Patients receiving SLE medications, n (%) | 1655 | (96.8) | 1710 | (100.0) | 0.343 |
| Class 1: antimalarials | 1174 | (68.7) | 1088 | (63.6) | 0.071 |
| Class 2: prescription NSAIDs | 605 | (35.4) | 582 | (34.0) | 0.504 |
| Class 3: corticosteroids | 1429 | (83.6) | 1357 | (79.4) | 0.173 |
| Oral | 1248 | (73.0) | 1092 | (63.9) | 0.001 |
| Infusion/injection | 580 | (33.9) | 692 | (40.5) | 0.002 |
| Topical | 252 | (14.7) | 237 | (13.9) | 0.498 |
| Class 4: immunosuppressants | 1005 | (58.8) | 869 | (50.8) | 0.002 |
| Number of claims per patient (mean, SD) | |||||
| Class 1: antimalarials | 2.15 | 2.05 | 2.00 | 2.07 | <0.001 |
| Class 2: prescription NSAIDs | 0.89 | 1.59 | 0.84 | 1.58 | 0.059 |
| Class 3: corticosteroids | 3.16 | 2.81 | 3.66 | 3.39 | <0.001 |
| Oral | 2.27 | 2.18 | 2.00 | 2.21 | <0.001 |
| Infusion/injection | 0.65 | 1.38 | 1.45 | 2.49 | <0.001 |
| Topical | 0.25 | 0.80 | 0.21 | 0.66 | 0.044 |
| Class 4: immunosuppressants | 2.10 | 2.50 | 1.73 | 2.35 | <0.001 |
| Number of classes, other than biologics, n (%) | |||||
| No therapy | 55 | (3.2) | 78 | (4.6) | 0.046 |
| One drug class | 220 | (12.9) | 297 | (17.4) | 0.001 |
| Two drug classes | 554 | (32.4) | 588 | (34.4) | 0.314 |
| Three drug classes | 639 | (37.4) | 565 | (33.0) | 0.033 |
| Four drug classes | 242 | (14.2) | 182 | (10.6) | 0.004 |
| Opioid use, n (%) | 901 | (52.7) | 861 | (50.4) | 0.341 |
| Weak opioids | 356 | (20.8) | 312 | (18.2) | 0.089 |
| Strong opioids | 699 | (40.9) | 695 | (40.6) | 0.915 |
| Acute opioid use (<90 days of cumulative drug supply) | 538 | (31.5) | 486 | (28.4) | 0.165 |
| Chronic opioid use (90+ days of cumulative drug supply) | 363 | (21.2) | 375 | (21.9) | 0.165 |
| Oral corticosteroid dosing† | |||||
| Average daily dose (mean, SD)ठ| 14.5 | 18.4 | 11.9 | 18.0 | <0.001 |
| Low average daily dose (>0 to <7.5 mg), n (%) | 210 | (12.3) | 255 | (14.9) | 0.037 |
| Medium average daily dose (7.5 to <15 mg), n (%) | 389 | (22.7) | 334 | (19.5) | 0.041 |
| High average daily dose (15+ mg), n (%) | 643 | (37.6) | 497 | (29.1) | <0.001 |
*Average follow-up time after biological index was shorter than average follow-up time after SLE diagnosis, especially among the belimumab cohort, so inclusion criteria required a 6-month preindex/postindex period of continuous enrolment to maintain the sample size.
†Claims with ≤0 value for fields used to calculate dose were dropped (<1% of patients without a valid claim).
‡Daily dose in prednisone equivalents=(strength × quantity)/days of supply. Claims with ≤0 value for fields used to calculate dose were dropped (resulted in dropping <1% of patients without a valid claim), therefore n went from 1248 to 1242 patients when reporting these results.
§For those with an invalid daily dose (>100 mg/day), doses were capped at 100 mg. This occurred for <2% of belimumab patients in both time periods reported.
NSAIDs, non-steroidal anti-inflammatory drugs.