Targets where the ligand is described in the comment field
Target	Comment
C5a1 receptor	The C5a1 receptor is currently referred to as C5aR1 in the literature. C5a1 has been an attractive target for pharmacological inhibition to treat a myriad of inflammatory and neurodegenerative diseases. Several C5a1 antagonists have been reported that have progressed to various stages of clinical development [4,8,11], although none are yet approved for use in humans. The non-peptide C5aR1 inhibitor CCX168 (Avacopan®), developed by ChemoCentryx/Amgen, is currently the most clinically advanced C5aR1 inhibitor [1]. The drug was approved by the FDA in October 2021, as an adjunctive treatment in adults for severe active ANCA-associated vasculitis (specifically microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA)) in combination with standard therapy including glucocorticoids [7]. Considering the potential benefits of blocking the C5a-C5a1 axis to limit myeloid infiltration and prevent excessive lung inflammation in Coronavirus disease 2019 (COVID-19) [2], the two anti-C5a/C5a1 blocking antibodies, avdoralimab (IPH5401) and vilobelimab (IFX-1), were studied in patients with COVID-19 severe pneumonia (NCT04371367 and NCT04333420) [13].