CKD or Membranous Nephropathy.

Patient of 20 yr Male has been developed Sudden facial swelling & Foamy urine and test has been done suggested by doctors & Diagnosed with hyperuricemia treated with tablets for 1 month...KFT was normal . Responded well with medication. Then upto 1 year allergies reactions continues like cold  sneezing ignored them assuming as minor disease or any allergy. After 1 year random blood test KFT was done and Serum creatinine was 5 mg/dl ... kidney biopsy has been done suggested of anti PLA2R Membranous Nephropathy with acute  renal tubular damage then blood test of Anti PLA2R was negative. Treatment - Immunosuppressive Drugs has been started Mycophenolate sodium & Steroid but no huge improvement. Kindly provide your guidance for further directions of treatment.