VEGF superagonists and methods of use

Inventors

Szkudlinski, Mariusz W. • Weintraub, Bruce D.

Assignees

Trophogen Inc

Abstract

Modified VEGF proteins that inhibit VEGF-mediated activation or proliferation of endothelial cells are disclosed. The analogs may be used to inhibit VEGF-mediated activation of endothelial cells in angiogenesis-associated diseases such as cancer, inflammatory diseases, eye diseases, and skin disorders.

Core Innovation

The invention relates to modified vascular endothelial growth factor (VEGF) proteins and analogs that are designed to increase receptor binding affinity compared to wild-type VEGF. In particular, the modified VEGF includes substitutions at amino acid residues E44, E72, and E73, where the substitutions introduce a positively charged amino acid. The resulting VEGF variants are described as VEGF receptor antagonists that dissociate receptor binding affinity from VEGF bioactivity and angiogenic effects on endothelial cells.

The problem addressed is that VEGF bioactivity and angiogenic signaling require control, including in diseases associated with angiogenesis. The described modifications aim to increase binding to native VEGF receptors, preferably KDR/VEGFR2, while substantially decreasing VEGF bioactivity and angiogenic effects on endothelial cells. Additional design principles include optionally reducing co-receptor and neuropilin-1 binding by disrupting cysteine residues.

The invention further provides variants and formats that include modified homodimers/heterodimers, single-chain or linker constructs, and fusion proteins, including VEGF-toxin fusion proteins, as well as nucleic acids and expressing vectors, and pharmaceutical compositions. Additional optional modifications are described for protease resistance and serum half-life, and for altered pharmacokinetics and stability. Examples include analogs such as I83K, E44R, E72R+E73R, E67K, and Q87K with measured changes in KDR binding and reduced or modulated endothelial proliferation.

Claims Coverage

The partial independent claim coverage comprises one independent claim directed to a modified VEGF protein with specified residue substitutions that increase receptor binding affinity versus wild-type VEGF. Dependent claims refine the independent claim by specifying the sequence context, restricting the identity of the positively charged amino acid, adding additional substitutions, and optionally limiting packaging/format and pharmaceutical composition inclusion.

Across the independent claim and refinements in the provided claim set, the main inventive concept is to engineer VEGF with positively charged substitutions at E44/E72/E73 in SEQ ID NO: 4 or SEQ ID NO: 13 to increase receptor binding affinity versus wild-type VEGF, with further constraints on residue identity and optional addition of other specified substitutions such as A148, as well as inclusion in pharmaceutical compositions.

Stated Advantages

Documented Applications