Mountain View Pharmaceuticals, Inc. (MVP), a privately-held California corporation with expertise in the application of advanced polymer-coupling technology to make protein-based drugs safer and longer acting, has announced its receipt of US Patent No. 8,129,330 B2 titled “Polymer Conjugates with Decreased Antigenicity, Methods of Preparation and Uses Thereof.”

MVP also announced the publication of a peer-reviewed scientific article, titled “Role of the Methoxy Group in Immune Responses to mPEG-Protein Conjugates” in the American Chemical Society journal, Bioconjugate Chemistry.

“The US patent that was issued to MVP on March 6 has been granted more than five and-one-half years of patent term adjustment, in recognition of the long delay between the filing of the application in 2002 and issuance of the patent. As a result, this patent is not scheduled to expire before mid-2028,” stated Dr Eldora Ellison, MVP’s lead patent attorney at Sterne Kessler Goldstein & Fox, in Washington, DC.

The new publication supports MVP’s development of PharmaPEG conjugates and the patent protects the relevant intellectual property. PharmaPEG is MVP’s registered trademark for the most advanced generation of poly(ethylene glycol) (PEG). PharmaPEG forms less antigenic and less immunogenic conjugates than methoxyPEG (“mPEG”), which has been used in all existing PEGylated drugs.

For a wide variety of proteins, including enzymes, serum proteins and cytokines, the reductions in immune responses to PharmaPEG conjugates, compared with mPEG conjugates of the same proteins, have ranged from 3-fold to >1,000-fold, as reported in Bioconjugate Chemistry. The decreased immunoreactivity results from replacement of the methoxy group of mPEG by a hydroxy group at the end of the polymer that is not attached to the protein.

Patents disclosing and claiming PharmaPEG conjugates have been granted to MVP previously in 18 other countries. MVP’s recently issued US patent, which includes 94 claims covering PharmaPEG conjugates of numerous classes of proteins, glycoproteins and peptides, will be a key component of the Company’s business development and licensing activities.

“MVP’s PharmaPEG technology is the product of more than a decade of research and represents a major advance directed toward the multi-billion-dollar market for PEGylated proteins,” said Dr Merry R Sherman, CEO and president of MVP.

“MVP’s publication illustrating the advantages of PharmaPEG-protein conjugates, compared with conventional mPEG-protein conjugates, is expected to reach a wide audience of academic scientists, immunologists and pharmaceutical professionals.”