AB0464 THE ROLE OF CYCLOPHOSPHAMIDE CHEMOTHERAPY IN THE TREATMENT OF EOSINOPHILIC GRANULOMATOSIS WITH POLYANGIITIS

Abstract

Background:Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare type of ANCA associated Vasculitis (AAVs). Cyclophosphamide (CYC) is generally recommended for the induction of remission in life/organ threatening AAVs in combination with glucocorticoids. However, due to its rarity, randomized controlled trials regarding the efficacy of treatment modalities in EGPA are hard to perform. Therefore, the level of evidence for the use of CYC in the treatment of EGPA is lower when compared to other AAVs (1).Objectives:The aim of this study is to investigate common therapeutic agents used for the treatment of patients with EGPA.Methods:Medical records of patients who were followed-up with the diagnosis of EGPA between 2007-2020, in rheumatology clinics of Ankara and Adana Hospitals of Başkent University, were analyzed retrospectively. Treatment outcomes were assessed.Results:Records of 11 patients (six females) were analyzed. The median age was 47 (19-77) years. The median follow-up time of the patients was 24 (9-156) months. Six patients were diagnosed with asthma. The median time between the diagnosis of asthma and EGPA was 4.5 (1-3) years. Five patients had tissue biopsies. Biopsy locations were terminal ileum, lung, myocardium and nerve. The most common forms of involvement were asthma, eosinophilic pneumonia and / or nodule, cardiovascular involvement, mononoritis multiplex, vasculitic skin rash, arthritis and bowel involvement, respectively. P-ANCA was positive in 8 patients. Three patients had myocarditis and cardiomyopathy, and two patients had isolated valve problems. The median BVAS value at the time of diagnosis and the third month of treatment was 17 (6-27) and 4 (2-7), respectively.Nine patients used oral 1mg/ kg methylprednisolone (MP) and 500mg CYC every two weeks as an induction therapy. The cumulative median CYC dose was 4.5 g (1.5-8). Neither of the patients developed CYC related side effects. MP was tapered to 2 mg in five patients, and was quited in two patients. Azathioprine (AZA) was used in remission treatment following CYC therapy. Rituximab (RTX) therapy 1 g twice, 2 weeks apart was initiated in two patients due to unresponsiveness to CYC. While RTX was effective in one patient, newly developed renal involvement was detected after the third cycle of RTX therapy in other patient. Two patients had pregnancy plan therefore they used AZA plus MP as induction. A patient had mycophenolate mofetil plus MP due to AZA allergy. All patients are currently in remission except one patient.Conclusion:In seven out of 11 EGPA patients, long-term remission was achieved with CYC treatment. CYC appears to be an effective and inexpensive method of first-line treatment for organ threatening EGPA.