The avacopan story, stronger again: (recall: avacopan targets C5aR) endogenous anti-C5aR1 in GPA inversely correlates with dx activity, relapse questions, via chair @philseo: What happens to anti-C5aR1 with Rx? Does this influence therapeutic strategy? #ACR20 ABST2050 @RheumNow https://t.co/g4JfjQal8R