Long-acting compstatin analogs comprising a clearance-reducing moiety attached to two compstatin analog moieties, each compstatin analog moiety comprising a cyclic peptide extended by a lysine residue or a sequence comprising a lysine residue at the N-terminus, C-terminus, or both, wherein the lysine residue is separated from the cyclic portion of the peptide by a rigid or flexible spacer comprising an oligo(ethylene glycol) moiety, the clearance reducing moiety comprises a linear polymer, wherein each end of the linear polymer is linked to one of the compstatin analog moieties by way of a carbamate, wherein (i) the spacer comprises —(CH2)m— and —(O—CH2-CH2—)n joined covalently, wherein m is between 1 and 10 and n is between 1 and 10； and/or (ii) the spacer comprises 8-amino-3,6-dioxaoctanoic acid (AEEAc) or 11-amino-3,6,9-trioxaundecanoic acid.
