One-year real-world effectiveness with avacopan in granulomatosis with polyangiitis and microscopic polyangiitis in a large healthcare system

Author(s):

Naomi Patel ¹, Andrew King ², Madison Negron ³, Zachary Williams ⁴, Ana Fernandes ¹, Nora Shepherd ², Colebrooke Johnson ¹, Guy Katz ¹, Belen Arevalo Molina ¹, Elizabeth Ibiloye ⁵, Sam Oh ⁶, Zachary Wallace ⁷, Sebastian H Unizony ⁸

¹ Massachusetts General Hospital, Boston, MA, USA;  ² Massachusetts General Hospital, Boston, MA, USA;  ³ Harvard Extension School, Medford, MA, USA; ⁴ Massachusetts General Hospital, Nancy, KY, USA;  ⁵ Amgen Inc, Thousand Oaks, CA, USA;  ⁶ Amgen Inc, South San Francisco, CA, USA;  ⁷ Massachusetts General Hospital, Newton, MA, USA;  ⁸ Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.

Abstract or description:

Objective: To assess the 12-month effectiveness and safety for avacopan users in a large healthcare system.
 

Methods: 
This ongoing retrospective cohort study included patients with granulomatosis with polyangiitis (GPA)/microscopic polyangiitis (MPA) who were prescribed avacopan from 12/1/21-4/1/24. Sustained remission (SR) at month 12 was defined as Birmingham Vasculitis Activity Score version 3 (BVAS v3)=0 at months 6 and 12, no glucocorticoid use for GPA/MPA 1 month before months 6 and 12, and no relapse from months 6-12. Relapse (1 or 2 minor BVAS v3 items for ≥2 consecutive visits, or ≥1 major item, or ≥3 minor items) was assessed after 1 month. Other related outcomes were also assessed.
 

Results: 
Among 119 patients prescribed avacopan (mean age 59.4 years, 70% female, 66% newly diagnosed, 50% GPA, 55% MPO-ANCA+), median (IQR) baseline BVAS v3 was 12 (8, 17). Among 95 patients initiating avacopan with available 12-month follow-up data, 90 (95%) had BVASv3=0, and 83 (87%) were glucocorticoid-free; 58 (61%) had SR at month 12. Three patients relapsed between months 6-12. Overall, 38 (40%) were still on avacopan at 12 months, and 57 (60%) discontinued therapy before 12 months mostly due to completion of the provider’s planned treatment course (33/57, 58%) or adverse events (14/57, 25%). Among 84 patients on glucocorticoids at baseline, 72 discontinued glucocorticoids after a median (IQR) of 84 (56, 175) days.
 

Conclusion: In this real-world GPA/MPA cohort, most avacopan users discontinued glucocorticoids within 3 months and had SR at 12 months; a minority had avacopan-related adverse events.