The invention is directed to modified Coversin polypeptides which exhibit leukotriene or hydroxyeicosanoid binding activity and reduced or absent C5 binding relative to the unmodified Coversin polypeptide； to nucleic acid molecules encoding said modified Coversin polypeptides； vectors and host cells comprising said nucleic acid molecules； and methods of treating or preventing diseases or conditions mediated by a leukotriene or hydroxyeicosanoid in a subject comprising administering said modified polypeptides or nucleic acids to a subject.
