Comparison of the Efficacy of Two Rituximab Treatment Regimens in Patients With Lupus Nephropathy (RITULUP)

• Rate of complete or partial response in lupus nephritis [ Time Frame: Assessment at 12 months ] [ Designated as safety issue: No ]

  Complete response defined as:

  • Glomerular Filtration Rate (GFR)≥ 60, 73 m2 (or decline to baseline or

    ± 15% of baseline in those with GFR <60 ml/min/1, 73m2).

  • Proteinuria ≤ 0.5 g/24 hours.
  • Inactive urine sediment (red cells, white cells, red cell casts according to local laboratory ranges).
  • Serum albumin> 3 g / dl

  Partial response defined as:

  In patients with proteinuria ≥ 3.5 gr/24 h , decreased proteinuria <3.5 gr/24 hours.

  • In patients with baseline proteinuria <3.5 gr/24 hours, reduced proteinuria> 50% of baseline.
  • In both situations, stabilization (± 25%) or reduce of the Glomerular Filtration Rate.
  
  

• Renal function [ Time Frame: 24 months of follow-up ] [ Designated as safety issue: Yes ]
  Proportion of patients achieving a stabilization of renal function (Glomerular filtration rate of ± 25% over baseline or serum creatinine within normal range)
  
  
• Safety [ Time Frame: 24 months of follow-up ] [ Designated as safety issue: Yes ]
  Incidence of adverse events, serious adverse events and adverse events that led to the interruption of the study.
  
  
• Rescue medication [ Time Frame: 24 months of follow-up ] [ Designated as safety issue: Yes ]

  Need for immunosuppressive treatment added to the experimental pattern:

  1. - Mycophenolate
  2. - Azathioprine
  3. - Methotrexate
  
  
• Efficacy [ Time Frame: 24 months of follow-up ] [ Designated as safety issue: Yes ]
  Improvements in Selena-SLEDAI (Systemic Lupus Erythematosus Disease Activity Index) score results
  
  

Randomized, open, controlled, multicenter, clinical trial in patients with lupus nephritis previously treated with cyclophosphamide and mycophenolate. These patient can not have received Rituximab in the previous year. The number of patients estimated to reach statistical significance is 18 in each arm, a total sample size of 32 patients is needed.

The hypothesis is that the alternative procedure (a second cycle of Rituximab)will reduce the relapse rate of lupus nephritis and the consequent deterioration of renal function. Besides it will reduce health care expenses(hospitalization, medication, hemodialysis and renal transplantation).