The Full Court decision in Actavis Pty Ltd v Orion Corporation  FCAFC 121 potentially limits the effectiveness of a definition of ‘comprises’ in a specification.
In many jurisdictions, the word ‘comprises’ when used in a patent claim is understood to be inclusive, such that a claim to a compound comprising A, B and C will not usually be understood to exclude the presence of D. In Australia however, a number of Court decisions mean that the term is usually construed as being exclusive. It is therefore common practice to include in a specification a definition of the term stating that it is used inclusively.
In Actavis Pty Ltd v Orion Corporation, claim 17 of the patent defined:
A method for preparing an oral solid composition comprising entacapone, levodopa, and carbidopa, or a pharmaceutically acceptable salt or hydrate thereof, wherein the method comprises:
a. mixing pharmacologically effective amounts of entacapone and levodopa, or a pharmaceutically acceptable salt or hydrate thereof, with at least one pharmaceutically acceptable excipient and a disintegrant to obtain a first mixture;
b. granulating the first mixture to obtain a granule batch;
c. adding a pharmacologically effective amount of carbidopa, or a pharmaceutically acceptable salt or hydrate thereof, optionally a lubricant, and optionally one or more pharmaceutically acceptable excipients to the granule batch to obtain a second mixture;
d. formulating the second mixture into a plurality of dosage forms.
For the purpose of determining infringement, the Court needed to decide whether claim 17 included a process in which the amount of levodopa added in step a) could be a low, but nevertheless pharmacologically effective, dose and a further amount of levodopa added in a later step, such as step c), provided that the addition, at the later step, did not compromise the pharmacological effectiveness of the overall composition. The trial judge had held such a process to be within the scope of the claim.
The Full Court considered that the plain reading of claim 17 suggests that the process is one in which there is an intended pharmacologically effective amount of each active agent and that this pharmacologically effective amount is added at the designated process step specified in the claim. The only reason to read the claim otherwise was based on a definition of the word ‘comprises’ in the specification – namely, that its use in the description and claims ‘is not intended to exclude other additives, components, integers or steps’.
It was held that this indication in the specification must be borne in mind when construing claim 17, but that it could not contort the claimed process into a substantively different process. It could not give the word ‘comprise’ and its variants an unbridled operation, when the relevant description and claims themselves specify, with appropriate precision, the step or steps to be taken that will provide the promised advantage. Accordingly, the better reading of claim 17 was that the word ‘comprises’ must yield to the direction that the intended pharmacologically effective amounts of each active agent must be added at the step in the process that is specified for that addition.