Clinical trials in lupus nephritis

The Steroids In the Maintenance of remission of Proliferative Lupus nephritis (SIMPL) pilot trial

Background

Patients with proliferative lupus nephritis are at risk of frequent relapses. Whether low- dose prednisone prevents relapses is uncertain.

Objectives

We undertook a pilot RCT to determine the feasibility of a larger trial.

Design

Pilot randomized controlled trial.

Setting

Single center Canadian outpatient nephrology clinic.

Patients

Participants with systemic lupus erythematosus (SLE) and a history of class III or IV lupus nephritis that achieved at least partial remission and remained on prednisone were eligible.

Measurements

Feasibility: proportion of eligible patients randomized and adherence to tapering regimen. Clinical: occurrence of renal or major non-renal flare of SLE.

Methods

We conducted a blinded, two-parallel-group randomized controlled trial of prednisone 7.5 mg/day (continuation) compared to a matching placebo (withdrawal).

Results

Of nineteen eligible patients screened, 15 (79%) were recruited and randomized; 8 to prednisone continuation and seven to withdrawal. All participants adhered to the tapering protocol to their assigned withdrawal or low-dose maintenance target. Over 36 months, the primary outcome occurred in four (50%) patients in the continuation group (three renal and one major non-renal flare), compared with one patient (14%) in the withdrawal group (one renal flare). Three participants (38%) in the continuation group had minor flares, while no patients in the withdrawal group did.

Limitations

This pilot RCT was small and not designed to assess the efficacy or safety of maintenance with low-dose prednisone.

Conclusions

The high proportion of eligible patients recruited, and success of protocol adherence suggest a large trial of prednisone maintenance therapy compared to withdrawal is feasible.

Trial registration

Current Controlled Trials ISRCTN31327267.

Treatment for lupus nephritis

BACKGROUND

Lupus nephritis is the renal manifestation of systemic lupus erythematosus (SLE) - a disease mainly affecting young women with substantial morbidity and mortality. It is classified by the World Health Organization (WHO) criteria I - VI based on histology. WHO Class IV is a diffuse proliferative glomerulonephritis which has the worst prognosis without treatment, with a reported 17% five year survival in the era 1953-1969. This survival was 82% in the early 1990's and continues to improve. An important factor behind this has been the use of cytotoxics such as cyclophosphamide in addition to steroids.

OBJECTIVES

To assess the benefits and harms of different treatments in biopsy-proven proliferative lupus nephritis (LN).

SEARCH STRATEGY

We searched the Cochrane Renal Group's specialised register (January 2003), the Cochrane Central Register of Randomised Controlled Trials (CENTRAL - The Cochrane Library issue 1, 2003), MEDLINE (1966 - 31 January 2003), EMBASE (1980 - 31 January 2003) and handsearched reference lists of retrieved articles.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs comparing treatments for PLN in both adult and paediatric patients with Class III, IV, Vc, Vd lupus nephritis were included. All treatments were considered.

DATA COLLECTION AND ANALYSIS

Data was extracted and quality assessed independently by two reviewers, with differences resolved by discussion. Dichotomous outcomes are reported as relative risk (RR) and measurements on continuous scales are reported as weighted mean differences (WMD) with 95% confidence intervals. Subgroup analysis by study quality, drug type and drug route have been performed where possible to explore reasons for heterogeneity.

MAIN RESULTS

Of 920 articles identified, 25 were RCTs suitable for inclusion, which enrolled 915 patients. The majority compared cyclophosphamide or azathioprine plus steroids versus steroids alone. Cyclophosphamide plus steroids reduced the risk of doubling of serum creatinine (RR 0.59, 95% CI 0.40 to 0.88) compared to steroids alone but had no impact on mortality (RR 0.98, 95% CI 0.53 to 1.82). The risk of ovarian failure was significantly increased (RR 2.18, 95% CI 1.10 to 4.34). Azathioprine plus steroids reduced the risk of all cause mortality compared to steroids alone (RR 0.60, 95% CI 0.36 to 0.99), but did not alter renal outcomes. Neither therapy was associated with increased risk of major infection. No benefit was found with addition of plasma exchange to cyclophosphamide or azathioprine plus steroids for mortality ( RR 0.71, 95% CI 0.50 to 1.02), doubling of serum creatinine (RR 0.17, 95% CI 0.02 to 1.26) or end-stage renal failure (RR 1.24, 95% CI 0.60 to 2.57). There was also no increased risk of major infection (RR 0.69, 95% CI 0.35 to 1.37).

REVIEWER'S CONCLUSIONS

Until future RCTs of newer agents are completed, the current use of cyclophosphamide combined with steroids remains the best option to preserve renal function in proliferative LN. The smallest effective dose and shortest duration of treatment should be used to minimise gonadal toxicity, without compromising efficacy.