complement C5   Click here for help

GtoPdb Ligand ID: 8712

Immunopharmacology Ligand
Comment: This is the full length, pre-pro-protein structure as represented in NCBI Reference Sequence: NP_001726. This peptide is cleaved into the complement C5 beta chain, complement C5 alpha chain and C5a anaphylatoxin (see the UniProt entry for the human protein P01031).

C5 inhibition is a clinically validated mechanism that is utilised for the control and suppression of complement-induced hemolysis in patients with paroxysmal nocturnal hemoglobinuria (PNH). Eculizumab is a clinically approved anti-C5 monoclonal antibody for PNH. Investigational Phase 1/2 anti-C5 monoclonal RG6101 (SKY59 [4]; IMGT 783) was granted FDA orphan drug designation in September 2017 for the treatment of paroxysmal nocturnal hemoglobinuria (PNH). Ra Pharmaceuticals is developing a C5 binding synthetic 15-amino-acid macrocyclic peptide (designated research code RA101495; Phase 2) for PNH and other complement-mediated illnesses. RA101495 was granted FDA orphan drug designation for PNH in July 2017. RA101495 binds to a site on C5 distinct from the eculizumab binding site, with the aim of overcoming eculizumab resistance, such as that observed in patients with the Arg885His C5 variant [6] (note that RA101495 is also effective against this variant [4]). It is also designed for subcutaneous self-administration, which would be more convenient for patients, who must be given eculizumab by i.v. infusion by a healthcare professional.

SARS-CoV-2 and COVID-19: Clinically approved and investigation candidates that target C5 are being evaluated in a number of clinical trials to determine their potential to combat complement-mediated inflammatory tissue damage in the organs of pateints with severe COVID-19.
Species: Human
Other ligands which bind to or alter the activity of this ligand
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Ligand Sp. Type Action Value Parameter Concentration range (M) Reference
tesidolumab Peptide Primary target of this compound Hs Antibody Binding 10.9 – 11.7 pKd - 2
pKd 10.9 – 11.7 (Kd 1.2x10-11 – 2x10-12 M) [2]
Description: Binding to full length human C5.
eculizumab Peptide Approved drug Primary target of this compound Hs Antibody Binding 9.2 – 10.5 pKd - 3,8
pKd 10.5 (Kd 3x10-11 M) [3]
pKd 10.5 (Kd 3x10-11 M) [8]
Description: At pH7.4 in a SPR assay.
pKd 9.2 (Kd 6x10-10 M) [8]
Description: At pH6.0 in a SPR assay.
crovalimab Peptide Hs Antibody Binding 9.8 pKd - 7
pKd 9.8 (Kd 1.5x10-10 M) [7]
Description: Binding affinity at pH7.4
pozelimab Peptide Approved drug Hs Antibody Binding 9.6 pKd - 5
pKd 9.6 (Kd 2.6x10-10 M) [5]
ravulizumab Peptide Approved drug Primary target of this compound Hs Antibody Binding 7.7 – 9.3 pKd - 8
pKd 9.3 (Kd 4.9x10-10 M) [8]
Description: At pH7.4 in a SPR assay.
pKd 7.7 (Kd 2.2x10-8 M) [8]
Description: At pH6.0 in a SPR assay.
pozelimab Peptide Approved drug Monkey Antibody Binding 8.1 pKd - 5
pKd 8.1 (Kd 8.55x10-9 M) [5]
zilucoplan Peptide Approved drug Hs Inhibitor Binding - - - 1
[1]