Ph20 Polypeptide Variants, Formulations And Uses Thereof

What is this patent about?

’600 is related to the field of hyaluronidase enzymes , specifically modified forms of the PH20 hyaluronidase. Hyaluronidases degrade hyaluronan, a key component of the extracellular matrix. Native PH20 increases tissue permeability and facilitates the dispersion of therapeutic agents. However, existing hyaluronidases, particularly those from non-human sources, can be immunogenic and may lack optimal stability for therapeutic applications. Therefore, there is a need for improved hyaluronidases with enhanced stability and reduced immunogenicity.

The underlying idea behind ’600 is to engineer PH20 variants with improved properties by modifying the amino acid sequence. The key inventive insight is that specific amino acid replacements can alter the stability and activity of the enzyme. By identifying residues that contribute to stability under various conditions, such as elevated temperature, agitation, low salt, or the presence of denaturing excipients, it is possible to create modified PH20 polypeptides with enhanced therapeutic potential .

The claims of ’600 focus on a modified PH20 polypeptide with at least 95% sequence identity to SEQ ID NO:3 or 32-66, excluding any signal sequence. The claims specifically cover a modified PH20 polypeptide comprising an amino acid modification at a position corresponding to position 320 with reference to amino acid positions set forth in SEQ ID NO: 3, and wherein the modification at position 320 is selected from among H, K, Rand S. The claims also cover a method for manufacture of a protein, comprising preparing a plasmid DNA containing a cDNA encoding the protein comprising an amino acid sequence, wherein the protein is a modified PH20 polypeptide.

In practice, the invention involves creating a library of PH20 variants with different amino acid replacements. These variants are then screened for their ability to degrade hyaluronan under various conditions, such as in the presence of preservatives or at elevated temperatures. Variants that exhibit improved stability or activity are selected for further development. The modified PH20 polypeptides can be produced recombinantly in cells, such as CHO cells, and purified using standard protein purification techniques.

The invention differentiates itself from prior approaches by providing specific amino acid replacements that enhance the stability and activity of PH20. Unlike previous hyaluronidases, the modified PH20 polypeptides of the present invention are engineered to withstand harsh conditions, such as those encountered during formulation and storage, while maintaining their enzymatic function. This leads to improved pharmaceutical compositions with longer shelf lives and enhanced therapeutic efficacy. The site-directed mutagenesis approach allows for precise control over the enzyme's properties, resulting in a more robust and reliable therapeutic agent.