Repeat kidney biopsy findings of lupus nephritis patients in clinical remission treated with Mycophenolate associated with Belimumab or Mycophenolate plus standard of care therapy. A “post-hoc” analysis of participants in the BLISS-LN and open label extension study belonging to a single center

Background Lupus nephritis affects 40 to 70% of Systemic Lupus Erythematous(SLE) patients increasing their morbi-mortality; therefore, successful treatments are required to improve outcomes. Research Design and Study Sample In this paper 20 patients who participated in the BLISS LN trial at a single center (OMI) in Argentina were studied. All the patients continued Mycophenolate (MMF) treatment when the trial was finished and until a second biopsy was performed to determine the withdrawal of the immunosuppression according to the achieved clinical and histological response. Ten patients treated with MMF + Placebo versus 10 receiving MMF + Belimumab, were compared evaluating the complete clinical (CCR) and complete histological response (CHR) and the flares in each group. Results All the patients in the Belimumab group showed a CCR and 7 in the Placebo one; CHR was found in 9 and 5 patients of the Belimumab and Placebo group, respectively. None of the patients in the Belimumab group flared meanwhile two of the Placebo one did it. Conclusions Although the number of patients is insufficient to be able to draw unquestionable conclusions, adding Belimumab to the standard of care treatment with MMF would seem to increase the possibility of achieving a CCR, CHR, and a lower rate of relapses during treatment and long follow-up.