OXiGENE strengthens IP rights

OXiGENE, has been issued US Patent No.6,670,344, granting additional composition-of-matter claims for the company's lead vascular targeting compound, Combretastatin A4 Prodrug (CA4P).

It has in-licensed rights to this patent, entitled 'Combretastatin A-4 phosphate prodrug mono- and di-organic amine salts, mono- and di- amino acid salts, and mono- and di-amino acid ester salts,' from Bristol-Myers Squibb, which developed the novel salt forms of CA4P during a two-year research collaboration with OXiGENE.

The licence agreement gives OXiGENE exclusive worldwide rights to manufacture and commercialise all pharmaceutical products based on these new compositions, which are designed to provide significant improvements in stability and shelf-life advantage over the current chemical composition.

'We continue to strengthen our intellectual property portfolio and now have exclusive rights to 11 granted US patents and 18 pending patent applications, as well as their foreign counterparts, that cover aspects of our vascular targeting technology,' said Fred Driscoll, OXiGENE's president and chief executive officer. 'We expect the issuance of this patent to provide significant economic value to OXiGENE as we now have patent protection for CA4P composition until 2021, seven years beyond the term of the current composition-of-matter patent. To complement our patent protection in the United States, counterpart patent applications for these compounds have been filed in more than a dozen major international markets including Europe, Japan and Canada. Examination is underway in all of these countries and patents already have been granted in South Africa and Singapore.'

CA4P is being studied in six human clinical trials involving a total of approximately 200 patients. Five studies are underway in patients with various forms of cancer, including a Phase II trial in advanced anaplastic thyroid carcinoma, and one study is being conducted in patients with a non-life-threatening retinal disease known as wet age-related macular degeneration.

'The clinical conversion to these new salt forms is underway, and we believe that they should have no impact on the conduct of current or planned clinical trials,' said Dr Dai Chaplin, OXiGENE's chief scientific officer. 'It is important to realise that although the new salt forms confer a greater stability advantage than the existing form of CA4P, our preclinical studies to date indicate that there is no apparent difference in the safety or potency of the compounds in comparison with the current clinical form of the drug.'