The SRI-4 is a composite index of SLE disease improvement that consists of scores derived from the SLE Disease Activity Index 2000 (SLEDAI-2K), the British Isles Lupus Assessment Group (BILAG) 2004 Index, and the Physician's Global Assessment (PGA). Participants classified as responder if they met all of the following criteria: 1) ≥ 4-point reduction in the SLEDAI-2K total score; 2) no new severe disease activity (BILAG A organ score) or more than 1 new moderate organ score (BILAG B) compared with baseline; and 3) No worsening from baseline in participants' lupus disease activity (i.e., increase of ≥0.3 0 on a 3-point scale) in PGA. The SLEDAI-2K total score falls between 0 and 105, with higher scores representing increased disease activity. SLEDAI-2K: assesses improvement in disease activity (range: 0 to 105; higher score = higher severity). BILAG: assesses disease extent, severity (range: A\[severe\] to E\[no disease\]). PGA: assesses worsening in participant's general health.

The BICLA is a responder index developed to measure response to therapy, and it includes scores from the BILAG, SLEDAI-2K, and Physician's Global Assessment (PGA). BICLA response is defined as: 1) at least 1 gradation of improvement in baseline BILAG 2004 scores in all body systems with moderate disease activity at entry (eg, all B \[mild disease\] scores falling to C \[Stable and mild\], or D \[no activity\]); 2) no new BILAG A or more than 1 new BILAG B scores; 3) no worsening of total SLEDAI-2K score from baseline; 4) ≤ 10% deterioration in PGA score. The PGA is measured on a 0 to 100 mm scale with score 0 indicates No Disease Activity and score 100 indicates the most Severe Disease Activity.