Belimumab plus standard therapy | Standard therapy | P-value | |

5-year SDI score change (95% CI) (n=181)* | 0.265 (0.180 to 0.350) | 0.718 (0.548 to 0.889) | |

Difference (95% CI) | –0.453 (–0.646 to 0.260) | <0.001 | |

Rate of organ damage progression (n=323)* | |||

HR vs standard therapy (95% CI) | 0.397 (0.275 to 0.572) | – | <0.001 |

Intercept hazard rate (95% CI) | – | 0.078 (0.064 to 0.096) | <0.001 |

Annual probability of progression^{†} | 3.1% | 7.5% | – |

Magnitude of year-on-year organ damage progression (n=323)* | |||

≥1-point SDI increase events, n (%) | 41 (12.7) | 87 (26.9) | – |

≥2-point SDI increase events, n (%) | 2 (0.6) | 26 (8.0) | – |

Proportion of ≥2-point SDI increase events/≥1-point SDI increase events, n/n (%) | 2/41 (4.9) | 26/87 (29.9) | – |

*n values presented are equal for each cohort.

†The annual probability of SDI progression was derived using the hazard rate estimates from the proportional-hazards exponential regression model.

CI, confidence interval; HR, hazard ratio; SDI, Systemic Lupus International Collaborating Clinics/American College of Rheumatology (SLICC/ACR) Damage Index.