Ligand's OmniAb® therapeutic antibody platforms, OmniRat®, OmniFlic®, OmniMouse® and OmniChicken™, produce highly diversified, fully human antibody repertoires optimized in vivo for manufacturability, therapeutic efficacy and reduced immunogenicity - Naturally optimized human antibodies®. The single-license OmniAb offering is the industry's only with three species and multiple genetic backgrounds to address even the most challenging targets - 3 species, 1 license™.

OmniRat and OmniFlic are the only rats available for generation of mono- and bispecific human antibodies. OmniMouse and OmniChicken provide complementary murine and avian systems for the industry's widest epitope coverage.

OmniAb animals have clear freedom-to-operate and enable generation of antibodies specific for any target and indication globally (unlike some genetically engineered mice on the market), except for a few named therapeutic targets that are excluded for OmniChicken. To date, more than 30 biopharmaceutical companies and several universities have established unlimited OmniAb access. OmniAb antibodies have been generated against hundreds of targets and several are now in clinical development with many more pending. The uptake has been very strong since OmniRat was launched in 2012 and the other OmniAb platforms a couple of years later.

OmniRat, OmniFlic and OmniMouse were developed, validated and commercialized by Open Monoclonal Technology, Inc. ("OMT") until the company's acquisition by Ligand in January 2016. OMT created a novel rodent immunoglobulin gene knock-out technology and in 2009 reported generation of the world's first rats with completely inactivated immunoglobulin loci in the journal Science. Subsequent insertion of recombinant immunoglobulin loci resulted in OmniRat animals that were demonstrated to express a diverse repertoire of antibodies with fully human idiotypes as well as wildtype animals produce normal antibodies, another scientific-first. OMT subsequently used the same platform to develop OmniMouse and OmniFlic.

OmniChicken was developed, validated and commercialized by Ligand's team in 2016 - it was the first successfully engineered bird with an immune system that could efficiently generate human sequence antibody repertoires. OmniChicken repertoires have been demonstrated to feature a high level of functional diversity, with sequence diversity focused in the CDR regions while maintaining conserved, highly developable FW regions. In 2019, the Ligand team released OmniClic, a transgenic chicken that has been engineered to focus sequence diversity only on the CDRs of the VH domain, leaving VL domains germline in sequence. OmniClic derived antibodies are useful in developing bispecific antibodies using a common light chain strategy. Both OmniChicken and OmniClic share the benefit of affinity maturing antibodies in the phylogenetically distant chicken host environment, which has been proven to be very valuable in delivering diverse antibody panels to highly conserved therapeutic targets that are poorly immunogenic in mammals.

OmniAb animals are bred on multiple genetic backgrounds by certified, domestic and international breeders. OmniAb antibody discovery services are available from Ligand-approved contract research organizations ("CROs") in the US, Europe and Asia. These services may offer the most cost-efficient way to generate and characterize therapeutic OmniAb antibodies. In the case of rodents, OmniAb licensees can may also procure animals directly from the breeders and conduct the antibody discovery internally.