Ph20 Polypeptide Variants, Formulations And Uses Thereof

What is this patent about?

’520 is related to the field of modified PH20 hyaluronidase polypeptides . Hyaluronan (HA) is a key component of the extracellular matrix, particularly in connective tissues, and its degradation is crucial for various physiological processes. Hyaluronidases, like PH20, catalyze HA degradation, increasing tissue permeability and aiding the dispersion of therapeutic agents. Existing hyaluronidases, often derived from ovine or bovine sources, can be immunogenic in humans, creating a need for improved enzymes with enhanced stability and activity.

The underlying idea behind ’520 is to engineer PH20 variants with improved properties through amino acid modifications. The core inventive insight involves identifying specific amino acid residues within the PH20 polypeptide that, when replaced, lead to increased stability and/or activity. This is achieved by systematically modifying the PH20 sequence and screening the resulting variants for desirable characteristics, such as resistance to denaturation under various conditions like elevated temperature, agitation, low salt, or the presence of denaturing excipients.

The claims of ’520 focus on a modified PH20 polypeptide that includes one or more amino acid modifications in an unmodified PH20 polypeptide. The unmodified PH20 polypeptide consists of the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7 and 32-66. The amino acid modifications are selected from the group consisting of amino acid replacements(s), deletion(s), and/or insertion(s). The modified PH20 polypeptide comprises an amino acid replacement at a position corresponding to residue 324, with reference to amino acid positions set forth in SEQ ID NO: 3; the replacement at the position corresponding to residue 324 is selected from the group consisting of A, D, H, M, N, R and S; corresponding amino acid positions are identified by alignment of the PH20 polypeptide with the polypeptide having the amino acid sequence of SEQ ID NO: 3; and the modified PH20 polypeptide has at least 91% sequence identity to a polypeptide having the amino acid sequence selected from the group consisting of SEQ ID NO: 3, 7 and 32-66.

The invention works by systematically introducing amino acid replacements into the PH20 polypeptide and then screening the resulting variants for improved characteristics. The screening process involves assessing the hyaluronidase activity of the modified polypeptides under various stress conditions, such as elevated temperatures or in the presence of preservatives. Variants that exhibit enhanced activity or stability under these conditions are then selected for further development and characterization. This iterative process allows for the identification of PH20 variants with optimized properties for therapeutic applications.

This approach differentiates itself from prior art by providing a library of modified PH20 polypeptides with specific amino acid replacements that enhance stability and activity. Unlike previous hyaluronidases that may suffer from immunogenicity or instability, the engineered variants in ’520 are designed to overcome these limitations. By focusing on specific amino acid modifications, the invention offers a targeted approach to improving the therapeutic potential of PH20, leading to more effective and reliable enzyme formulations.