Article Text
Abstract
Objective We evaluate the efficacy of human umbilical cord-derived mesenchymal stem cell (hUC-MSC) for the treatment of lupus nephritis (LN). Previous reports showed hUC-MSC could have dramatic treatment effect.
Methods Eighteen patients with WHO class III or IV LN were randomly assigned to hUC-MSC (dose 2×108 cells) or placebo. All patients received standard immunosuppressive treatment, which consisted of intravenous methylprednisolone and cyclophosphamide, followed by maintenance oral prednisolone and mycophenolate mofetil.
Results Remission occurred in 9 of 12 patients (75%) in the hUC-MSC group and 5 of 6 patients (83%) in the placebo group. Remission was defined as stabilisation or improvement in renal function, reduction in urinary red cells and protein. A similar proportion of patients on hUC-MSC and placebo achieved complete remission. Improvements in serum albumin, complement, renal function, Systemic Lupus Erythematosus Disease Activity Index and British Isles Lupus Assessment Group scores were similar in both groups. One patient on placebo had a stroke and another had ascites. One patient on hUC-MSC had leucopenia, pneumonia and subcutaneous abscess and another died of severe pneumonia. The trial was abandoned after 18 patients were enrolled when it had become obvious it would not demonstrate a positive treatment effect.
Conclusion hUC-MSC has no apparent additional effect over and above standard immunosuppression.
Trial registration number NCT01539902; Results.
- Systemic lupus erythematosus
- Lupus Nephritis
- Mesenchymal Stem Cell
- randomized controlled trial
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Introduction
Systemic lupus erythematosus (SLE) is a multisystem disease characterised by abnormalities of T and B cells and production of autoantibodies. Renal involvement occurs in approximately 40%–75% of patients and is associated with increased morbidity and mortality. Severe proliferative lupus nephritis (LN) is associated with a poor renal prognosis and requires aggressive therapy. SLE has traditionally been treated using immunosuppressive drugs including steroids, intravenous cyclophosphamide (CYP) and mycophenolate mofetil (MMF). An alternative therapeutic approach is to exploit the immunomodulatory effect of stem cells.1 Indeed, many reports have shown that allogeneic human umbilical cord-derived mesenchymal stem cell (hUC-MSC) could have dramatic treatment effect in severe refractory SLE.2–7 However, data from randomised trials are lacking.
Methods
We conducted a prospective, randomised, double-blind clinical trial at a single centre in Kunming, China. The study was conducted in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. The institutional review board of the study sites approved the protocol, and all patients gave written informed consent.
Study patients, randomisation and blinding
Patients aged 16 years or older who had SLE fulfilling American Rheumatism Association criteria with WHO class III or IV LN, Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) score >8 and the British Isles Lupus Assessment Group (BILAG) score A/B, proteinuria greater than 1 g/day and active urinary sediments were enrolled into the study. Exclusion criteria were serum creatinine >250 µmol/L, white cell count <2.5×109/L, evidence of major infection, history of cancer, allergy, alcohol or substance abuse, active peptic ulcer disease, heart failure, liver disease, coagulation disorder and pregnant or lactating women.
Eligible patients were randomised centrally in a two-to-one ratio to receive hUC-MSC or placebo. The randomisation code was generated using the random permuted block method with randomly varying block size. Both study investigators and patients were blinded to the treatment assignment.
Immunosuppressive protocol
All patients received standard immunosuppressive drug treatment as follows:
Induction therapy, which consisted of pulse intravenous methylprednisolone at the discretion of the investigator plus low-dose intravenous CYP six pulses at a fixed dose of 500 mg every 2 weeks. After the first 11 patients were treated in this fashion, the induction CYP was modified as rescue treatment. This means investigator may consider initiating CYP 4 weeks after patients have been given study treatment (hUC-MSC or placebo). Earlier initiation (before 4 weeks) of CYP was however permitted at the discretion of the investigator.
Following the induction therapy, all patients received maintenance oral prednisolone, starting at 60 mg/day for 4–6 weeks then decreasing dose over a period of 3–4 months until a maintenance dose of between 5 and 10 mg/day was achieved, and maintenance oral MMF 1 g two times per day.
Study assessments and endpoints
Patients were reviewed every 2 weeks for the first 2 months, then every month for 2–6 months on trial and thereafter every 2 months for the rest of the duration of the trial (12 months). Evaluation included physical examination, full blood count, erythrocyte sedimentation rate, urinalysis, 24 hours urine protein, renal profile, liver function test, fasting lipids, fasting glucose, antinuclear antibody (ANA), complement C3 and C4 concentration and the SLEDAI8 and BILAG9 scores.
The primary outcome was remission of nephritis (combined partial and complete remission (CR)) defined as stabilisation or improvement in renal function, urinary red blood cells of less than 10 per hpf and reduction of proteinuria to less than 3 g/day if baseline proteinuria was more than 3 g/day or at least a 50% reduction in proteinuria or to less than 1 g/day if baseline proteinuria was in the subnephrotic range. Stabilisation of renal function was defined as change in serum creatinine concentration of less than 20% compared with baseline concentration and improvement in renal function was defined as a reduction in serum creatinine of at least 20% compared with baseline. CR was similarly defined except for reduction of proteinuria to less than 0.3 g/day. Secondary endpoints were improvement in SLEDAI and BILAG scores, complement concentration, anti-dsDNA (double-stranded DNA) antibody and ANA titres, death and commencement of permanent dialysis or renal transplantation.
Results of efficacy analysis were reported as the proportion of subjects with remission. All endpoint analyses were performed on an intention-to-treat basis, with all randomised patients who had received at least a dose of study treatment included in the analyses. The Cockcroft and Gault formula was used to compute creatinine clearance.10
Results
We enrolled 18 patients between February 2012 and February 2013. Of the 18 subjects screened and randomised, all patients had received their treatments as randomised as shown in figure 1. One patient in the hUC-MSC group died after 3 months on trial. All other patients in both groups completed the trial. The trial was abandoned after 18 patients were enrolled when it had become obvious that the trial would be unlikely to demonstrate a positive treatment effect for hUC-MSC.
Baseline features
Table 1 shows the baseline characteristics of the patients in the two arms of the trial. They were similar except for significantly higher baseline proteinuria in the placebo group compared with the hUC-MSC group. No patient had renal impairment (creatinine clearance less than 60 mL/min) at baseline.
hUC-MSC treatment
The 12 patients randomised to hUC-MSC arm received a total dose 2×108 cells each. It is dispensed in a phial containing 5×107 cells suspended in a medium. Two phials were administered intravenously to each patient two times at a 7-day interval apart. No local or systemic complications were reported. For the first 11 patients enrolled, the hUC-MSC were administered concurrently with the intravenous methylprednisolone and CYP induction therapy, and for the 12th to 18th patients enrolled, the hUC-MSC were administered concurrently with the intravenous methylprednisolone only and intravenous CYP was delayed to 4 weeks later.
Trial outcomes
All 18 patients completed 12-month observation on trial except for one who died 3 months after enrolment. Remission occurred in nine (75%) patients in the hUC-MSC group and five (83%) in the placebo group. The mean time to remission was 9 and 16 weeks for the hUC-MSC and placebo groups, respectively (table 2).
Proteinuria decreased steadily in both arms, while serum albumin has increased (figure 2). Although the placebo group had a higher baseline proteinuria, the reduction in proteinuria over time was parallel to the hUC-MSC group. The proteinuria decreased from 4.49±3.43 g at baseline to 3.11±2.73 g at 6 months in the placebo arm and from 3.08±1.75 g at baseline to 0.97±0.98 g at 6 months in the hUC-MSC group.
Serum creatinine remained stable in both groups (figure 2). At the end of 6 months, there was no significant difference in serum creatinine between the two groups (mean serum creatinine was 59.00±9.21 and 62.92±17.77 µmol/L in the placebo and hUC-MSC groups, respectively).
There was also improvement in other indices of SLE and LN activity. These included the SLEDAI and BILAG scores, anti-dsDNA antibody and ANA titres and serum C3 and C4 concentrations (table 2). There were no significant differences in these parameters between groups. One patient in the hUC-MSC group died during the trial.
Serious adverse events
Four serious adverse events (SAE) occurred to four patients during the trial. Two events occurred to two patients on placebo and similarly two on the hUC-MSC arm. One patient on placebo had a stroke and another had ascites of unknown cause. One patient on hUC-MSC had leucopenia, pneumonia together with subcutaneous abscess, from which she recovered. Another had severe pneumonia which she died of.
Conclusion
We conducted a prospective, randomised, double-blind clinical trial of hUC-MSC versus standard immunosuppression in patients with newly diagnosed severe LN. Unfortunately, the trial was abandoned after 18 patients were enrolled when it had become obvious that the trial would be unlikely to demonstrate a positive treatment effect for hUC-MSC. Nevertheless, the available data showed that we were unable to reproduce the previously reported2–7 dramatic treatment effect of hUC-MSC in severe refractory SLE.
While hUC-MSC has no apparent additional effect over and above standard immunosuppression in severe LN as shown in this trial, this does not mean hUC-MSC has no immunosuppressive effects at all. These effects have been clearly demonstrable in other inflammatory immune-mediated diseases such as graft versus host disease11 and Crohn’s disease.12
The protocol prespecified definition of nephritis remission, a measure of response to treatment as reported here, is consistent with, but differs slightly from, the definition of the European consensus criteria.13 Post hoc reanalysis of the data according to European consensus criteria gives similar result and did not change the study conclusion.
Acknowledgments
The authors thank the two companies, Beike Biotech and CytoMed Sdn Bhd, for providing the hUC-MSCs.
References
Footnotes
Contributors DD, PZ, YG and TOL participated in the original conception of the research idea, design of the study, development of the study protocol, study conduct at the trial site, analysis of the data, writing and revision of the paper.
Funding This research was funded by Beike Biotech and CytoMed Sdn Bhd.
Competing interests None declared.
Ethics approval This study was approved by the institutional review-board of the 2nd Affiliated HospitalKunming Medical University.
Provenance and peer review Not commissioned; externally peer reviewed.
Data sharing statement There is no additional unpublished data from the study. The authors will make available all data from this research for purpose independentverification of the results or for use in meta-analysis.