Effect of Cyclophosphamide Versus Mycophenolate Mofetil in Induction Therapy of Lupus Nephritis in Nepalese Population

Systemic lupus erythematosus (SLE) is an autoimmune disease associated with multiple organ involvement, among which kidney involvement, also known as lupus nephritis (LN), is quite common in SLE. LN is associated with a more than four-fold increase in mortality in patients with SLE. The management of SLE and LN comprises timely and coordinated management consisting of initial or induction phase of aggressive immunosuppression to bring the active disease under control followed by maintenance phase. The initial phase usually lasting for six months consists of treatment with steroid and cyclophosphamide or mycophenolate mofetil. So far there is no study published regarding the efficacy and adverse events of such treatments in Nepal. So, this study aimed to evaluate and compare the effectiveness and safety profile of mycophenolate mofetil and intravenous pulse cyclophosphamide in induction therapy of LN in Nepalese population.

A total of 52 patients with international society of Nephrology/ renal pathology society (ISN/RPS) class III to V lupus nephritis were screened, 3 of which did not meet entry criteria and 49 patients were enrolled in the study comprising of 25 and 24 patients in the MMF and CYC group respectively. Twenty one patients in each groups could complete the study till the end of 6 months and were included for analysis.

Patients in the CYC group received intravenous cyclophosphamide (CYC) in the dose of 0.5 to 1 gram per m2 of body surface area. The medicine, which is available in the strength of 1 gram in powder form, was first dissolved in 20 ml of normal saline. Only15 ml of this preparation was mixed in 100 ml of normal saline and was infused over a period of one hour. CYC was not given to those patients who had total leukocyte counts (TLC) less than 2500/mm3. Those patients were re-evaluated after one week and intravenous pulse CYC was reinstituted if the total leucocyte count (TLC) exceeds 2500/mm3. Pulse CYC was administered every month for a total of six infusions.Patients were monitored monthly and the details were recorded. During follow ups, any adverse events in between were noted and detailed physical evaluation was done and all baseline investigations (except USG abdomen, chest X-ray, serum anti nuclear antibody (ANA) and anti double strain deoxy-ribonuccleic acid (anti dsDNA), complement factor 3 (C3) and complement facotr 4 (C4) level) was repeated. Fasting lipid profile was repeated at the end of third and sixth month of treatment.

During the course of treatment, if a patient had interruption of medication for less than a 10 days' period due to any reason, s/he was considered as a regularly included subject. If the interruption extended beyond 10 days, the patient was withdrawn from the study.

Patients in the MMF group were administered tablet mycophenolate mofetil at a starting dose of 500 mg twice daily if the weight of the patient was less than 50 kilograms and 750 mg twice daily if the weight was more than 50 kilograms. After one month, the dose of MMF was increased to 750 mg twice daily. The clinical response was monitored in terms of reduction in serum creatinine and proteinuria. MMF dose was decreased or interrupted in patients experiencing an absolute neutrophil count <1300/mm3 at any study visit; MMF treatment was discontinued if a patient experienced an absolute neutrophil count <1000/mm3.