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Patent considerations in the immunotherapy space: Claiming by the method of producing the antibody

The present article follows on from our previous articles in the series and discusses a third type of format that could be used in claims to protect antibody inventions. This is otherwise known as claiming by the method of producing the antibody, which although is less popular than claiming by structure and claiming by function or target, is still important to discuss. 

Claiming by the method of producing the antibody

The production of antibodies by unconventional methods or processes represents a permissible form of antibody claiming if it can be demonstrated that routine methods of producing the same would not yield the same results.

  • Europe

Product-by-process antibody claims are usually only allowed before the EPO if the antibody cannot be defined by any other means. Some example claims that utilize this format of claiming include defining the hybridoma cell line, according to its accession number, that was used to produce said antibodies, as well as outlining an immunization protocol that results in production of the antibody.

In the case of T 1280/08 ‘Immunoglobulin products/STATENS SERUM INSTITUT’, for example, it was contended by the patentee that their new method of purifying IgG from a crude immunoglobulin-containing plasma protein fraction, was inventive, due to the technical complications in relation to using the starting material and the fragility of the immunoglobulins.

However, for an Applicant to utilize this type of claiming, the hybridoma should be deposited at a Depository Authority on or before the priority date of the application, in order to satisfy the requirements for written description, sufficiency and enablement, given that it is difficult to sufficiently describe hybridomas using structural language in a specification.

Unsurprisingly, claims that utilize this format are typically much narrower in terms of their scope of protection. Thus, it is highly recommended that at least some structural limitations are included in such claims, as reference to a hybridoma alone limits the scope of protection to the hybridoma per se, and does not limit the antibody claim to a particular sequence, as was discussed in an EPO Board of Appeal decision, T0032/17.

  • US

Similar to Europe, the US also permits claiming by the method of producing the antibody. However, unlike in Europe, where an antibody has not been sequenced, a biological deposit of hybridomas secreting the antibodies can be made at any time before allowance. Deposit of this assists with satisfying the written description requirements. Arguably, the scope of the claims will be quite narrow, as the claims would be directed to the hybridoma and antibodies produced by it.

  •  Australia

It is also possible to claim antibodies according to their method of production in Australia, similar to that described above for the US and for Europe. However, as per above defining antibodies by the hybridomas from which they are produced generally offers a narrow scope of protection.

Other strategies for protecting antibodies

As an additional point to consider, there is one other commonly used strategy for claiming antibodies, which involves defining the antibodies according to their medical or therapeutic use. Such methods of medical treatment are permitted in several jurisdictions, including in Australia and in the US. Although a variation of this sort of claiming, in the form of purpose-limited product claims (“substance X for use in the treatment of disease Y”), is permissible in Europe. A discussion on methods of medical treatment claims will be provided in a separate article. 

In the meantime, if you have any questions in relation to any of the above or in relation to any of our past articles in this series, please do not hesitate to contact our Life Sciences team who will be pleased to answer your questions. We wrap up our antibody series with another short article in the next few weeks, which will discuss some further considerations with respect to formulating an international strategy when seeking to file antibody patent applications that covers at least the jurisdictions of Australia, Europe and the US.