INTRODUCTION :
A prevalence study of systemic lupus erythematosus (SLE) in India showed a
crude incidence rate of 4 per 100,000 population per year. Lupus nephritis occurs in
about half of SLE patients (range: 35%-73%) in India. Most patients with SLE do not
present initially with renal disease; only 25% of patients have this as their initial
presenting feature. In 5% of these cases, usually in men older than 40 years, it can be
several years before other lupus criteria or serological abnormalities develop.
Although the survival of SLE patients have improved in the west with modern
treatment to the tune of 80% at 10 years after diagnosis, among Indians the figures are
not so good (50%-60% survival at 10 years) as shown by Murali et al in a study of 98
patients between 1981 and 1993. Renal involvement in SLE is a therapeutic
challenge for all involved in the care of SLE, since early intervention can dramatically
change the disease course. Thirty or more years ago, few patients with severe grade IV
nephritis survived more than a year or two, and half of those with less severe form
of nephritis used to die within 5 years. After the introduction of Cyclophosphamide
into the therapeutic armamentarium of lupus nephritis 20 years later, renal involvement
no longer affects the survival rates of these patients. However, long-term treatment with
cyclophosphamide for patients with proliferative lupus nephritis is associated with
adverse effects, including an increased risk of infection (10–18% per year). Cumulative
doses of cyclophosphamide over 9 g, particularly in women over the age of 32 years, are
associated with ovarian failure. The aim of treatment therefore, is to induce and
maintain remission of active nephritis with minimum toxicity. A major advance in
achieving the goal of identifying new therapies for the treatment of severe lupus nephritis
occurred in 2000, with the report by Chan [et al.] of the first prospective controlled study
comparing the efficacy and toxicity of Mycophenolate Mofetil (MMF) to oral
Cyclophosphamide in patients with diffuse proliferative lupus nephritis. Also for
maintenance therapy in lupus nephritis MMF seems to be a good alternative to azathioprine.
AIM :
To evaluate the Outcomes of Exposure-controlled Mycophenolic Acid as Induction and
Maintenance therapy in Class III and IV Lupus Nephritis.
OBJECTIVES :
1. To study the effect of Exposure-controlled Mycophenolic Acid on Inducing and Maintaining
remission in Class III and Class IV Lupus Nephritis patients.
2. To study the side effect profile and complications of Mycophenolic Acid therapy in Lupus
Nephritis.
CONCLUSIONS :
1. Mycophenolate Mofetil is beneficial as both induction an maintenance therapy
in lupus nephritis.
2. With an empiric dosing schedule of 30mg/kg/day of Mycopheolate Mofetil
(MMF), 55.8% of patients had 6 hour MPA AUC below the therapeutic range of
30-60mg.h/L and 5.8% of patients had 6 hour MPA AUC above the therapeutic
range.
3. After dose adjustment, the average dose of MMF required to attain therapeutic
range was 35mg/kg/day in our study population.
4. 57.6% had complete remission at 12 months in exposure controlled Mycophenolic
Acid cohort and 50% had partial remission by 3 months. The complete remission
rates improved through the maintenance phase to 88% at the end of two years.
Partial remission was seen in 50% of the patients at three months. Cumulative
remission which is the sum of complete and partial remission was seen in 94% at
3 months. This is comparable to studies on Cyclophosphamide as induction
therapy and Azathioprine as maintenance therapy.
5. GFR was the earliest to improve with a median time of 2.6±0.85 months.
6. Proteinuria improved next at a median time of 3±1.3 months followed by Anti
dsDNA at 4±0.3 months.C3 was the last to remit among the lab parameters at a
median time of 12±2.4months.
7. There were four flares with majority being mild nephritic flares that did not
require any modification of immunosuppression.
8. Infectious episodes were present 17.3% in the cohort