This list is very much based on my personal experience. The purpose is to provide examples of the
sorts of problems that can occur on biotech cases. This allows development of pre-empting
strategies, such as making sure the application contains the appropriate
fallback positions.
1. Claiming Gene and Protein Sequences Which Are Homologues
Of Prior Art Sequences
Examiners are increasingly strict in allowing claims to
sequences which are homologues of prior art sequences, probably due to the
perception that is technically easy to obtain such sequences. Thought should be
given as to why the skilled person might have thought the claimed sequence did
not exist, what technical difficulties were overcome during cloning and what advantages
the new sequence gives.
2. Claims That Cover Homologues Of New Gene And Protein Sequences
It has generally been the case that Examiners would allow
applicants to claim sequences which had homology of 65-70% to a new
gene/protein sequence as long as a functional limitation was also recited, such
as ‘retaining kinase activity’. However
increasingly Examiners are likely to ask for further structural descriptions of
the functional sequences. Thought should
therefore be given to fallbacks which specify which sequence positions need to
be the same as the cloned sequence to retain activity. In addition experimental work describing the
properties of homologues should be included in the application if it is
available.
3. Claims To Antibodies
Examiners seem to be getting stricter on all aspects of
antibody patenting, both in terms of defining the antibody and showing that it
has inventive step. If possible the specific epitope sequence bound by the
antibody should be given and fallbacks should be introduced which define what
the antibody does not bind. In addition
it would be very helpful to have data showing surprising properties of the
antibody, such as high levels of affinity or specificity. If the prior art is close then bear in mind
that the onus is on the applicant to show novelty and appropriate fallbacks
will need to be present to define the antibody so that it is clearly novel.
4. Claims Referring To Conditions That Are Defined Functionally
Sometimes the invention is relevant to more than one disease
condition in which case a functional definition is appropriate for defining the
condition in the claims (e.g. a condition in which TNF-α levels are elevated). In this situation Examiners can be very
strict on making sure that the specific conditions which are covered can be
identified by the skilled person. In my
experience limitation to specific defined conditions is often required and it
is rare for Examiners to allow claims that only define a condition
functionally.
5. Claims To Mutant Proteins With Specific Activities
If the invention concerns finding a mutant enzyme with a new
or improved activity, then it can be difficult to claim all mutants that would
have that activity. One must consider
how to define equivalent mutations at the same or other positions, as well as
how best to cover homologous proteins with the same mutation. Clearly having data showing activity in a
range of mutants would be helpful.
6. Claims To Diagnosis By Detecting All Relevant Polymorphisms
In A Gene
Where the invention concerns the finding that polymorphisms
in a specific gene can be used to diagnose susceptibility to a disease
condition then it can be difficult to claim all possible polymorphisms that
could form the basis of the diagnostic test.
Claims to detection of specific listed polymorphisms for which data is
available should be possible, but claims to polymorphisms which are in linkage
disequilibrium to them might not possible, though such linked polymorphisms
could be identified by routine means.
7. Claims To Use Of A Crystal Structure To Design A Molecule
Where the invention concerns the deducing of a crystal
structure then it should be possible to obtain claims covering use of the
specific structure to design molecules bind or modulate the molecule that has
been crystallised. However it can be
difficult to obtain claims covering use of any crystal structure of the
same molecule that can be obtained in the same way (i.e. Use of a crystal structure
obtainable by [crystallisation, X-ray diffraction and computation steps] to
design a modulator of protein X).
Clearly claims which are limited to use of a specific set of coordinates
would be very narrow.
8. Claims To A Composition Defined Functionally
Where the invention relates to a large number of
compositions which cannot easily be defined by specifying the amounts of each
component then a functional definition can be appropriate (e.g. A composition comprising
component A and component B in synergistic amounts). Whether or not an Examiner will accept a
functional definition will be decided on a case-by-case basis, and therefore
the assumption should not be made that a functional definition will not be accepted.
9. Claims To A Product Which Solves More Than One Problem
Under European practice the problem solution approach is
used to assess inventive step. Normally all of the claims will be analysed with
reference to the same problem being solved.
However given that products, such as molecules, will have more than one
property they can be solutions to different problems, some of which are obvious
and some which are not. As a simplistic
example, if the invention concerns the discovery that adding a (novel) protein
with a specific sequence to a composition causes stabilisation of the
composition, and this property of the protein is not obvious, it might still
not be possible to obtain a claim to the protein per se if it has homology to
known proteins. Finding homologues to
known proteins can be deemed to be obvious by Examiners (solving the problem of
providing another protein with similar properties, say), and so claims to them
can be difficult to obtain even where they turn out to have surprising
properties which provide an inventive solution to a problem.
10. Claims To All Functionally Equivalent Epitope Sequences
Where the invention concerns identification of a T cell
epitope sequence then it should normally be possible to cover homologues of the
epitope. However it can be difficult to
define a functional limitation for the homologues which is acceptable to the
Examiner. A reference to a complex test,
such as ‘capable of binding the same T cell receptor’ might not be acceptable. Thus thought needs to be given to providing
several different functional limitations.
