The World’s First Recombinant Polyclonal Drugs
We are advancing the first recombinant polyclonal antibody therapies for the treatment of infectious disease and transplant rejection, disorders that are currently treated with polyclonals derived from human or animal plasma. Polyclonal therapies are ideal for diseases that comprise many targets, for example, viruses that are best neutralized by a drug that binds multiple epitopes. Our candidates are engineered to be more potent, and therefore potentially more efficacious, than plasma-derived products. In addition, our candidates overcome the limitations inherent to existing products, which are subject to plasma supply shortages, variability from batch-to-batch, and risk for contamination from unwanted artifacts such as clotting factors.
- GIGA-2050 – Recombinant Anti-Coronavirus Immunoglobulin (rCIG):
Coronavirus disease 2019 (COVID-19) has caused hundreds of thousands of deaths and has devastated the world economy in 2020. Our approach to address the pandemic is to copy and re-create complete antibody repertoires of those who have recovered from COVID-19, specifically those who present a robust antibody response, and turn them into a drug that provides passive immunity to those severely ill or at high risk. We capture millions-diverse DNA libraries from B cell repertoires from convalescent human donors. These DNA libraries are then used to produce a recombinant polyclonal antibody product for treatment of severe COVID-19.
Unlike monoclonal antibodies, GigaGen’s recombinant anti-coronavirus immunoglobulin (rCIG), GIGA-2050, binds to a variety of viral epitopes, which may increase clinical efficacy. If novel virus variants arise, polyclonal antibodies are more likely to remain efficacious due to their binding diversity. Unlike plasma or serum polyclonal antibody methods, GigaGen only requires a few donors to generate enough product to treat millions of people.
Immune deficiencies are characterized by the body’s inability to properly make antibodies. Since antibodies are required to fight infection, patients with immune deficiencies are susceptible to recurrent and severe infections caused by viruses and bacteria that healthy people naturally fight off. Patients with immune deficiency are treated with intravenous immunoglobulin (IVIg), an antibody product derived from the plasma of thousands of human donors.
GigaGen’s recombinant IVIg replicates the antibody diversity of healthy vaccinated donors against selected common diseases. It is made by capturing millions-diverse DNA libraries from B cell repertoires from healthy, vaccinated human donors. These libraries are engineered into mammalian cells to re-create recombinant polyclonal antibody protein products. We have validated the purified, massively polyclonal protein products with in vitro and mouse models.
GigaGen’s recombinant IVIg has less risk of contamination, is not subject to plasma supply shortages, and is highly consistent from batch-to-batch. In addition, recombinant IVIg is engineered for higher potency than plasma-derived products.
During kidney transplant anti-thymocyte globulin (ATG) is used with other medications to prevent and treat transplant rejection. ATG is a plasma-based polyclonal typically derived from rabbit plasma, and therefore composed of rabbit antibodies.
We are developing a recombinant human ATG for kidney transplant rejection as an alternative to rabbit plasma derived ATG. Our recombinant product is more consistent from batch-to-batch, contains human antibodies and therefore is less immunogenic than rabbit ATG, and has the potential to provide improved efficacy with a less frequent dosing regimen.