Antigen Binding Proteins Targeting Beta-Klotho FGFR Complex

The patent creates antigen binding proteins (antibodies) that copy and mimic the biological effects of FGF21 by binding to the FGF21 receptor complex (β-Klotho-FGFR). These antibodies serve as functional copies of FGF21's signaling pathway activation, providing a stable therapeutic alternative that avoids the immunogenicity and instability issues of recombinant FGF21 protein administration.

The antigen binding proteins act as intermediary molecules that mediate the therapeutic effect. Instead of administering FGF21 directly (which causes immunogenicity), the antibodies serve as intermediaries that bind to the receptor complex and trigger the same metabolic regulatory signaling pathways, thereby achieving the therapeutic effect without the harmful side effects of direct FGF21 administration.

The patent uses antibody molecules that copy the functional outcome of FGF21 binding to its receptor. These antibodies are designed to be highly stable and non-immunogenic, serving as functional copies of FGF21's receptor-activating capability without triggering the immune system. This allows for long-term therapeutic efficacy without the immunogenicity problems of recombinant FGF21.

The patent employs antibody molecules that can be produced stably in host cells and have extended half-lives in vivo. These antibodies are designed to be resistant to degradation and immune clearance, providing a durable therapeutic effect without the need for continuous administration. The antibodies serve as stable, long-lasting therapeutic agents that replace the short-lived and immunogenic recombinant FGF21 protein.

The patent creates antibody molecules that copy the receptor-activating function of FGF21. These antibodies are engineered with extended half-lives through various modifications (e.g., Fc region engineering, glycosylation optimization) that prevent degradation and increase circulation time. This provides a durable therapeutic effect that lasts much longer than recombinant FGF21 protein, reducing the need for frequent dosing.

The patent applies parameter changes to the antibody molecules to extend their half-life. This includes modifying the antibody's physical and chemical properties (such as glycosylation patterns, Fc region sequences, and molecular weight) to optimize their stability and resistance to proteolytic degradation. These parameter changes result in antibodies with extended half-lives that maintain therapeutic activity for prolonged periods.