Domantis successful in patent opposition

Domantis Limited, the human Domain Antibody Therapeutics company, has successfully opposed European patent number EP0656946, leading to a major amendment of the main claim in the patent and a significant narrowing of the scope of 34 of the 41 other claims. The decision of the Opposition Division of the European Patent Office (EPO) reaffirms Domantis' complete freedom to operate in the field of human Domain Antibodies.

EP0656946 was awarded to VUB (Vrij Universiteit Brussel) and is subject to various licenses, including a license to Ablynx for the field of healthcare products. Ablynx is a Belgium based biopharmaceutical company engaged in the discovery of Nanobodies, which are heavy chain domain antibodies derived from camels and llamas ("camelids"). The EP0656946 patent is based on the elucidation at VUB of the structure of a particular class of camelid antibodies that consist solely of heavy chains (as opposed to human antibodies which consist of heavy and light chains). The patent was granted with a main claim (claim 1) covering such antibodies, as well as claims directed to heavy chains that have a charged or cysteine residue at position 45. This sequence feature has only ever been seen in a subset of heavy chain antibodies derived from camelids and not in any other species, including humans.

In contrast, Domantis' Domain Antibodies are based on the heavy or light chains of fully human antibodies and contain no components derived from animals. Over the last 30 years, antibody therapeutics have moved away from animal derived products due to side effects caused by the foreign nature of these proteins. Domantis is developing a range of therapeutic drugs based on its fully human Domain Antibodies and has a worldwide dominant patent position covering such products.

The Opposition Division of the European Patent Office, presiding in oral proceedings on Tuesday 30th August 2005, ruled that the main claim of the original EP0656946 patent and over 30 other claims were not patentable and instead required the narrowing of these claims to cover only heavy chains that have a charged amino acid or cysteine residue at position 45. The amended claims are therefore restricted to a specific feature that has only been reported in a subset of camelid heavy chain antibodies and do not apply to any of Domantis' heavy or light chain Domain Antibodies.

Domantis' CEO Robert Connelly commented, "We are delighted with the outcome of these proceedings. The decision by the EPO to dramatically narrow the scope of the EP0656946 patent reaffirms Domantis' dominant position and complete freedom to operate in the field of human Domain Antibodies, as underpinned by Domantis' extensive IP portfolio. The opposition confirms that this patent provides no coverage of any of Domantis' past, present or future activities."