NOBEX has been granted two new US patents on its polyethylene glycol (PEG)-based technologies to improve the delivery of drugs that currently need to be injected.
The company's PEGylation and related 'micro-alkylPEGylation' technology is being applied to the conversion drugs that currently require injection to those that can be given orally. It is already developing an oral insulin product for patients with diabetes with partner Biocon, an Indian biotechnology company.
Last October, the companies indicated that the collaborative effort in developing the oral insulin product will require several years to reach the market but that they expect to have meaningful clinical data andprogress toward manufacturing within two years.
The technology is particularly suited to the delivery of peptides, more and more of which are being identified as potential drugs, but is also suitable for small-molecules, according to the firm. Nd it is not restricted to oral dosage forms: studies suggest it can improve the delivery of injectable, inhaled and transdermal drugs as well.
The first patent (No 6,815,530) covers small molecular-weight PEG polymers in which substantially all of the PEG molecules have the same molecular weight. The patent covers such monodispersed PEG polymers as individual compositions of matter, as well as in combination with other components such as the alkyl and fatty acid compounds that NOBEX uses in its proprietary micro-alkylPEGylation technology for drug modification.
The second patent (No 6,835,802) covers synthetic methods for producing the monodispersed PEG and micro-alkylPEG ('oligomer') compositions.
Christopher Price, NOBEX' chief executive, said the patents not only protected Nobex development pipeline, but would also be of licensing interest to other companies using PEG-based polymers to modify their therapeutic molecules.
NOBEX modifies peptide drugs for oral delivery by chemically coupling the small, pure oligomers to the peptide at one or more selected sites, creating a new molecular entity. The oligomers are 'amphiphilic', i.e. they have a highly water-soluble portion (the PEG polymer) on one end and a highly lipid-soluble portion on the other end of a single structure. The balance of water and lipid solubility provided by the different polymers changes the chemical and biological properties of the drug.
The results are improvements in characteristics such as increased shelf stability, resistance to enzymes, absorption into the body from the gastrointestinal tract, and lengthened circulation time in the blood.
PEG polymers are well established in the biopharmaceutical industry for modifying the pharmacology of large protein drug molecules that are administered by injection, for example in the hepatitis treatments Pegasys (peginterferon alfa-2a) and PegIntron (peginterferon alfa-2b) from Roche and Schering-Plough, respectively. In these cases, large molecular weight PEG polymers are attached to the protein drug in random fashion and at variable numbers of sites on each molecule.
"This approach provides well-documented benefits to the pharmacokinetics and bioactivity of the PEG-modified drug administered by injection," said Nobex. However, PEG-modified proteins are not suited for delivery by the oral route of administration due to their very large size.