Successful use of avacopan in a case of ANCA-associated vasculitis with treatment-resistant medium-sized vessel involvement

Takaaki Tsuchiya; Yui Ohta; Masatoshi Oka; Kaoruko Fukushima; Shiho Matsuno; Noriko Yamanaka; Noriyuki Suzuki; Wako Yumura; Akiko Komatsu; Tomio Arai; Takashi Takei; Mitsuyo Itabashi

doi:10.1007/s13730-025-00965-8

Successful use of avacopan in a case of ANCA-associated vasculitis with treatment-resistant medium-sized vessel involvement

CEN Case Rep. 2025 Jan 24. doi: 10.1007/s13730-025-00965-8. Online ahead of print.

Authors

Takaaki Tsuchiya^{1

2}, Yui Ohta^{1

3}, Masatoshi Oka¹, Kaoruko Fukushima¹, Shiho Matsuno¹, Noriko Yamanaka¹, Noriyuki Suzuki¹, Wako Yumura⁴, Akiko Komatsu⁵, Tomio Arai⁵, Takashi Takei¹, Mitsuyo Itabashi⁶

Affiliations

¹ Department of Nephrology and Dialysis, Tokyo Metropolitan Institute for Geriatrics and Gerontology, 35-2 Sakae-Cho, Itabashi, Tokyo, 173-0015, Japan.
² Department of Nephrology, Tokyo Medical University, Tokyo, Japan.
³ Department of Geriatric Medicine, The University of Tokyo, Tokyo, Japan.
⁴ Division of Nephrology and Endocrinology, Tohoku Medical and Pharmaceutical University Hospital, Miyagi, Japan.
⁵ Department of Pathology, Tokyo Metropolitan Institute for Geriatrics and Gerontology, Tokyo, Japan.
⁶ Department of Nephrology and Dialysis, Tokyo Metropolitan Institute for Geriatrics and Gerontology, 35-2 Sakae-Cho, Itabashi, Tokyo, 173-0015, Japan. mitsuyo_itabashi@tmghig.jp.

PMID: 39849229
DOI: 10.1007/s13730-025-00965-8

Abstract

We report the case of a 75-year-old woman who presented with fever, right back pain, paresthesia in the right extremities, erythema, purpura, and nodules. She had previously initiated dialysis due to rapidly progressive glomerulonephritis and was transferred to our hospital. Imaging studies revealed multiple cerebral and splenic infarcts and hemorrhage encapsulating the right kidney, likely due to microaneurysms in multiple renal arteries. High MPO-ANCA titers were observed, and a skin biopsy revealed granulomatous inflammation affecting medium-sized vessels, leading to a diagnosis of granulomatosis with polyangiitis (GPA) and ANCA-associated vasculitis (AAV) involving medium-sized vessels. Treatment began with intravenous pulse steroid therapy (methylprednisolone 1000 mg/day) and subsequent oral prednisolone (PSL) 40 mg (about 0.8 mg/kg) and intravenous cyclophosphamide (IVCY) at 250 mg. While her symptoms improved, she developed severe infections, including candidemia and febrile neutropenia. Consequently, we combined PSL with the C5a receptor antagonist avacopan, which allowed for PSL tapering and stabilized her disease. This case is significant as no previous reports of avacopan's efficacy in AAV with medium-sized vessel involvement suggest its potential effectiveness in such cases.

Keywords: ANCA-associated vasculitis with medium-sized vessel involvement; Avacopan; Granulomatosis with polyangiitis; Microaneurysms in renal arteries.