Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Complement System

Complement System

The complement system is a group of approximately 20 plasma proteins that strengthen the body's defenses against infections through opsonization, inflammation, and cell lysis. Opsonization involves coating pathogens with complement proteins, making them more recognizable and facilitating phagocyte engulfment. Certain complement proteins induce inflammation that attracts immune cells to the site of infection. Cell lysis involves the destruction of pathogens through the formation of a...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Interleukin-6 is critical in the development of pulmonary vascular disease in <i>Gcn2-</i>deficient mice.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

ADAR2-Mediated RNA Editing Promotes TDP-43 Nuclear Export and Alters RNA Binding.

bioRxiv : the preprint server for biology·2026

Same author

An emergent disease-associated motor neuron state precedes cell death in ALS.

Cell·2026

Same author

Recent advancements and limitations of intestinal organoids for clinical applications.

Progress in biomedical engineering (Bristol, England)·2026

Same author

Routine whole blood use for primary postpartum haemorrhage in South India: A 12-year descriptive report.

Transfusion clinique et biologique : journal de la Societe francaise de transfusion sanguine·2026

Same author

Impact of microRNAs and long noncoding RNAs in skeletal and cardiac muscles.

Current opinion in physiology·2026

Search research articles

Related Experiment Video

Updated: Aug 7, 2025

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics DCAF

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics DCAF

Published on: September 17, 2019

SAR443809: a selective inhibitor of the complement alternative pathway, targeting complement factor Bb.

Vaishnavi Rajagopal¹, Nina Leksa¹, Ronald Gorham¹

¹Sanofi Research, Immunology & Inflammation Therapeutic Area, Cambridge, MA.

|March 10, 2023

Summary

A new drug, SAR443809, specifically inhibits the alternative pathway of the complement system by targeting factor Bb. This approach offers a promising therapeutic strategy for complement-mediated diseases by blocking C3 cleavage and reducing C3b deposition.

More Related Videos

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

Published on: July 18, 2017

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Published on: January 29, 2014

Related Experiment Videos

Last Updated: Aug 7, 2025

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics DCAF

Targeted Antibody Blocking by a Dual-Functional Conjugate of Antigenic Peptide and Fc-III Mimetics DCAF

Published on: September 17, 2019

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

High-resolution Melting PCR for Complement Receptor 1 Length Polymorphism Genotyping: An Innovative Tool for Alzheimer's Disease Gene Susceptibility Assessment

Published on: July 18, 2017

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells

Published on: January 29, 2014

Area of Science:

Immunology
Pharmacology
Drug Discovery

Background:

Complement system dysregulation is linked to various diseases.
Current complement inhibitors face challenges like high drug levels and incomplete effector function inhibition.

Purpose of the Study:

To discover and characterize SAR443809, a novel inhibitor targeting the alternative complement pathway's C3/C5 convertase (C3bBb).
To evaluate the therapeutic potential of SAR443809 in complement-mediated disorders.

Main Methods:

Discovery of SAR443809, a selective inhibitor of the alternative pathway C3/C5 convertase.
In vitro assays using patient-derived paroxysmal nocturnal hemoglobinuria erythrocytes.
Ex vivo experiments assessing hemolysis and C3b deposition.
Pharmacokinetic studies in nonhuman primates following intravenous and subcutaneous administration.

Main Results:

SAR443809 selectively binds to factor Bb, inhibiting alternative pathway C3/C5 convertase activity.
Proximal inhibition by SAR443809 abrogated both hemolysis and C3b deposition, unlike C5 blockade.
Sustained complement inhibition was observed for several weeks post-administration in nonhuman primates.

Conclusions:

SAR443809 demonstrates potent and selective inhibition of the alternative complement pathway.
This novel therapeutic agent shows potential for treating diseases driven by alternative pathway activation.
SAR443809 offers advantages over terminal pathway inhibitors by addressing both hemolysis and C3b deposition.