{
  "abstract": "Objectives Emerging therapies such as CAR-T-cells have been reported to induce deeper B-cell depletion and thereby drug-free remission up to 24 months. Anecdotally, we observed ‘RTX super-responders’ with sustained remission after one cycle (C1) of RTX. Our objectives were to assess a) incidence of RTX-super-response, with or without concomitant immunosuppressant (IS); and b) factors associated with long-response after C1 of RTX.Methods We conducted an observational study of consecutive RTX-treated SLE patients in a single centre over 20 years who had followed an on-demand retreatment strategy. B-cells were measured using highly sensitive flow cytometry. Univariable and multivariable (MVA) logistic regression analyses were performed to identify factors associated with RTX long-response.Results 114 were included in the study. Based on survival curve ( figure 1A), we defined RTX super-responders as >3 years. This occurred in 23/114 (20%) patients with median (IQR) duration of response of 263 (212,423) weeks.At baseline, RTX-super-responders had: mean (SD) age 35 (14) years, (ancestry European=39%; South Asian=26%, Chinese/SE Asian=9%; African=22%; and Mixed=4%), concurrent APS 6/23 (26%), median (IQR) disease duration 2.8 (1,5) years, median (IQR) SLEDAI-2K 11 (7,15), and median (IQR) numeric BILAG score 21 (13,25). Details of disease activity and B-cells over 3 years are provided in figure 1B. At 3 years, sustained suppression of plasmablasts was observed: median (IQR) 0.0008 (x 109/L) (0.0005,0.0034). 8/23 RTX-super-responders (34.8%) were not prescribed IS or withdrew them during follow up (drug-free remission).In MVA, factors associated with duration of response >3 years were non-European ancestry (OR 4.6, 95% CI 1.6-12.7) and concurrent APS, (3.2, 0.99-10.35), while longer disease duration (0.89, 0.80-0.99 per year) was associated with lower risk.Abstract PO:11:290 Figure 1–2Conclusions Sustained drug-free remission is not confined to patients treated with CAR-T CD19 but may be observed following RTX. In C1, one in five RTX-treated patients had >3 years response, and 1 in 12 had sustained, IS-free remission. RTX-super-response is associated with patient characteristics denoting disease severity (early disease, non-European ancestry and APS), as well as marked suppression of plasmablast repopulation. Given their safety and low cost, anti-CD20 mAbs in early poor-prognosis SLE may be preferable to intensive therapy in refractory disease.",
  "authors": [
    {
      "affiliations": [
        "Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"
      ],
      "name": "Md Yuzaiful Md Yusof"
    },
    {
      "affiliations": [
        "Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK"
      ],
      "name": "Junaid Patel"
    },
    {
      "affiliations": [
        "Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK",
        "NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK"
      ],
      "name": "Paul Emery"
    },
    {
      "affiliations": [
        "Leeds Institute of Rheumatic and Musculoskeletal Medicine, University of Leeds, Leeds, UK",
        "NIHR Leeds Biomedical Research Centre, Leeds Teaching Hospitals NHS Trust, Leeds, UK"
      ],
      "name": "Edward M Vital"
    }
  ],
  "title": "PO:11:290 Rituximab super-responders: clinical and B-cell characteristics of patients with more than 3 years response to a single cycle of treatment",
  "uid": "173ad08e-bf39-5ffa-9d28-bc9eeac22561"
}