Merial Limited v Argenta Manufacturing Limited - [2015] APO 51

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Merial Limited v Argenta Manufacturing Limited [2015] APO 51

Patent Application: 2012203345

Title:Delivery Devices and their Uses

Patent Applicant:  Argenta Manufacturing Limited
Opponent:  Merial Limited
Delegate:  Matt Kraefft
Decision Date:  18 August 2015
Hearing Date:  24 June 2015, in Melbourne

Catchwords: PATENTS – section 59 – opposition to grant of a patent – divisional application – lack of novelty raised only in respect of grandparent specification - earliest priority date valid – therefore lack of novelty argument invalid – inventive step – multiple types of intra-ruminal devices available in the art - inventive combinations of features in the present claims

Representation: Patent applicant: Mr Julian Cooke, of counsel, instructed by Dr Andrew Baker, patent attorney, AJ Park, Auckland.
Opponent:Mr John Landells and Mr David Herman, patent attorneys, FB Rice, Melbourne.

IP AUSTRALIA
AUSTRALIAN PATENT OFFICE
Patent Application: 2012203345

Title:Delivery Devices and their Uses

Patent Applicant: Argenta Manufacturing Limited
Date of Decision: 18 August 2015
DECISION
The opposition fails on all grounds raised in this opposition.
Subject to appeal, I direct the application proceed to grant.
REASONS FOR DECISION
Background

Argenta Manufacturing Limited (“the applicant”) filed patent application 2012203345 on 7 June 2012. The application is a divisional application of 2011213734 (“parent application”) which in turn is a divisional application of 2005209631 (“grandparent application”). The parent and grandparent applications have both lapsed. The grandparent application is based on a New Zealand provisional application, NZ 535258, filed on 9 September 2004. Accordingly the present application 2012203345 claims this date as its earliest priority date. Application 2012203345 was advertised accepted on 18 July 2013.
Merial Limited (“the opponent”) filed a notice of opposition on 18 October 2013. A statement of grounds and particulars followed on 17 January 2014. The opponent subsequently requested amendment of the statement of grounds and particulars to add an additional reference of alleged prior art. That request was allowed on 18 September 2014.
The parties completed the evidentiary stages on 22 September 2014.
Specification
The specification describes the invention as relating to intra-ruminal controlled release devices. Some declarants in this opposition have referred to these devices as intra-ruminal delivery devices (“IRDDs”). These devices are to provide specific delivery sequences of active ingredients to ruminant animals. The delivery of anthelmintic agents for worm control is the particular area to which the alleged invention pertains. Extensive background on the development of IRDDs and their uses is provided in the specification. Page 4 of the specification discusses the prior known problem of resistant worm populations and the solution of providing a priming dose to kill gut-resident, generally mature worm populations followed by a continuous dosing period to prevent or suppress re-establishment of new worm populations.
Page 6 of the specification outlines a subsequent problem with the priming or dump dose, particularly in respect to IRDDs of a type credited to a Dr Ralph Laby (“the Laby device”). The Laby device was characterised by a spring-driven stacked tablet delivery system (page 2). Another characteristic was that the device was a variable geometry device in that it comprised two foldable wings at one end of the device which expanded to an outward position after introduction into the rumen of an animal to retain the device in the rumen.
The device comprised a cylindrical container with a solid internal matrix core, which may be a plurality of tablets, spring loaded and biased towards the opening at the other end of the container for contact with ruminal fluid and for sequentially dissolving and releasing the tablet contents into the rumen. The problem with the priming or dump dose in the Laby or similar devices is that the use of rapidly dissolving formulations may break the moisture seal otherwise provided by spring-loading the tablets against the opening. The breaking of this moisture seal enables ingress of water around the outside of the tablets, resulting in the swelling of tablets along the stack and the jamming thereof in the barrel.
Whilst not explicitly stated in the specification, it appears the alleged invention purports to provide a solution to this problem. This problem may relate to further advancements in the art than any commonly known problem that may have been part of the common general knowledge of those skilled in the art in respect to IRDDs at the priority date. I will return to this issue later.
The specification ends with 30 claims. Aside from omnibus claim 30, the remaining independent claims are claims 1 and 21. These claims read as follows.
1.An intraruminal device comprising
an elongate body or body assembly substantially impervious to rumen fluids, the body defining a barrel having a first end and a second end and first outlet at the first end,
a first dose of an active agent within the body to be accessible to rumen fluid via substantially only the first outlet,
a second first (sic) dose of an active agent, and
at least one variable geometry device dependent from the body to assist rumen retention,
the second dose being located in
(i)a pocket in the body of the device, or
(ii)a cap, seal or encapsulation located over the first outlet, or
(iii)a cap, seal or encapsulation located at the second end, or
(iv)a combination of any two of (i) to (iii).
21. A method of providing an agent to a ruminant animal comprising
(i) providing an intraruminal device that comprises
a body with at least one outlet,
at least one variable geometry device dependent from the body or body assembly to assist rumen retention,
first agent or agents to be released with a dump-dose release profile,
a matrix of second agent or agents held in the body to be released with a continuous or sequential release profile,
(ii) administering the intraruminal device to the ruminant animal,
(iii) releasing the first agent or agents upon administration of the device as a dump-dose to expose the outlet of the body,
(iv) releasing the matrix of second agent or agents as a continuous or sequential release, and
wherein the outlet of the body limits the rate of dissolution of the matrix of second agent or agents to provide the continuous or sequential release profile of the second agent or agents.
Statement of Grounds and Particulars
The opponent’s statement of grounds and particulars listed nine grounds of opposition. These were that the nominated person was not entitled to a grant of a patent, that the invention was not for a manner of manufacture, that the claimed invention was not novel, did not involve an inventive step, was not useful and was secretly used, that the specification did not fully describe the invention, and that the claims were not clear and were not fairly based on the description. The opponent provided numerous particulars against these grounds.
Evidence in Support
The opponent filed evidence in support from Dr Stephen W. Page and Mr John Simon Landells. Dr Page consults in the area of livestock pharmacology and in particular on the use of veterinary medicines in livestock animals. He has worked in the animal health industry since about 1984 in various research, clinical development and managerial roles. Dr Page has commented on the state of the art before the priority date and the relevance of several exhibited documents against the invention as claimed. Mr Landells is a patent attorney with the firm representing the opponent. He has exhibited all of the same documents exhibited by Mr Page except one.
Evidence in Answer
The applicant filed evidence in answer from Mr Bruce Francis Chick, Dr John Winston Steel and Mr Michael Sean Venning. Mr Chick consults in the area of veterinary health research and development. He has extensive experience in this field since about 1972. Mr Chick has commented on the state of the art before the priority date, the problems encountered with the early standard Laby devices, and how the opponent’s prior art does not address the claimed invention. In respect to the prior art Mr Chick has noted the citing of essentially two types of IRDDs by the opponent, the Laby devices and osmotic devices. Mr Chick has stated that the cited Laby devices do not disclose the claimed features of the present application and that the prior art in respect to osmotic devices would be considered irrelevant in the present case since Laby and osmotic devices operate in accordance with entirely different operating principles. Dr Steel provides advice, project management expertise and consultancy work for authorities and companies in respect to pesticides, veterinary medicines and livestock parasite control. His expertise in one or more of these fields dates from the 1980s. Dr Steel’s evidence in the main supports Mr Chick’s evidence. Mr Venning has been the product development manager for the applicant and its predecessor since 1990. He is responsible for regulatory work with product registrations and clinical studies for new product development. Additionally Mr Venning has been employed by the company for 37 years. Mr Venning’s evidence in the main is similar to Mr Chick’s and Dr Steel’s evidence.
Evidence in Reply
The opponent filed evidence in reply from Dr Page, Dr Gottfried Lichti and Dr Keith James Ellis. Dr Lichti has run a consultancy company since 1994 specialising in providing advice in the field of formulation optimisation. Prior to that, Dr Lichti had worked in research, principally related to agricultural formulation science since the 1980s. Dr Ellis has worked as a consultant since 2003. Prior to that, he worked as a research scientist with CSIRO between 1978 and 2003. Before that, Dr Ellis worked in academia beginning in 1965. His principal area of expertise is animal health and behaviour, and the delivery of bioactive agents to livestock. All three declarants have commented on the state of the art before the priority date of the present application. They have also challenged the applicant’s evidence that persons skilled in the art would have considered devices such as osmotic devices to have been irrelevant compared with variable geometry devices such as the Laby device. On the contrary, the opponent’s declarants have essentially all stated they would have considered all types of available IRDDs when seeking improvements to the variable geometry device.
Applicable Law
As a consequence of the Intellectual Property Legislation Amendment (Raising the Bar) Act 2012 (“the Amendment Act”), there are substantial changes to the Patents Act 1990. The date of effect of those changes was 15 April 2013. The application of the Amendment Act depends on the date of the request for examination. The applicant filed its request for examination on 7 June 2012. Consequently the Patents Act as in force immediately before 15 April 2013 applies in the present case.
Section 18 of the Patents Act relates to patentable inventions. Relevant parts of subsection (1) appear below.
(1)Subject to subsection (2), an invention is a patentable invention for the purposes of a standard patent if the invention, so far as claimed in any claim:
(a)    is a manner of manufacture within the meaning of section 6 of the Statute of Monopolies; and
(b)   when compared with the prior art base as it existed before the priority date of that claim:
(i)is novel; and
(ii)involves an inventive step; and
(c)    is useful; and
(d)   was not secretly used in the patent area ………
Priority Date
Subsection 43(2) of the Patents Act at the relevant time provided that the priority date of a claim is either the filing date of the specification or a date otherwise determined by the Patent Regulations. Sub-regulations 3.12(1)(c) and 3.12(2C) relevantly provided that a claim of a divisional application, if fairly based on matter disclosed in the parent application, would take the priority date that the claim would have had if it had been included in the parent application.
Subsection 40(3) of the Patents Act at the relevant time required that the claims of a specification must be fairly based on the matter described in the specification. The Lockwood Security Products Pty Ltd v Doric Products Pty Ltd decision, [2004] HCA 58, 217 CLR 274, at [69], put this as a requirement that there be a real and reasonably clear disclosure of what is claimed. Both parties accepted this general proposition.
The Nichia Corporation v Arrow Electronics Australia Pty Ltd decision, [2015] FCA 699, further provided a useful summary of the law in respect to priority dates. At [56], Yates J referred to the decision in Vehicle Monitoring Systems Pty Ltd v Sarb Management Group Pty Ltd (No. 2), [2013] FCA 395, where at [121] it was stated that the test of fair basis for determining the priority date of a claim is not the same as the test under subsection 40(3). Referring back to the Nichia decision at [56], the latter test
“concerns claim width and is directed, in a general sense, to ensuring internal consistency between that which is described as the invention, and that which is claimed as the invention. This difference is reflected in the language of s40(3), which requires that a claim be fairly based on “the matter described in the specification”. In reg 3.12(1)(b), the inquiry is whether the claim is fairly based on “matter disclosed”. The significance of the omission of the definite article “the” in relation to “matter” in the test applied under reg 3.12(1)(b) was specifically referred to and discussed in Leonardis v Sartas No 1 Pty Ltd, (1996) 67 FCR 126 at 139, where the Full Court made clear that some part or parts of the overall disclosure made in the relevant priority document can provide “matter” on which a claim can be fairly based for the purpose of assigning a priority date to the claim.”
At [57], Yates J further stated:-
“Regard should also be had to the use of the word “disclosed” in reg 3.12(1)(b), contrasted with the word “described” in s 40(3). The word “described” as used in s 40(3) focuses attention on the invention that is required to be fully described in the specification: see s 40(2). However, in its particular context, the word “disclosed” in reg 3.12(1)(b) is a more general expression which, in conjunction with the word “matter”, reinforces that priority can be claimed by reference to some part or parts of the priority document.”
The opponent challenged the entitlement of the claims of the application to the claimed earliest priority date. In particular, the opponent submitted that the present specification extended beyond the invention described in the grandparent application and NZ application which were directed to using void spaces, for example a pocket or compartment, in the body of the device for separately containing a dump dose. The opponent thus accepted the feature of the second dose being located in a pocket in the body of the device (claim 1 item (i)) was not objectionable. By comparison, the opponent stated that the other items of claim 1 of the present application extended beyond the earlier applications to include a second dose located in a cap, seal or encapsulation which may or may not be rumen-erodible. The opponent essentially suggested the location of the second dose in a cap, seal or encapsulation over or outside the body of the device was an additional concept not contemplated in the grandparent application or NZ application. In this way, the opponent sought to distinguish the Lockwood decision since that decision concerned the omission of a feature from the claims rather than the addition of a feature in the claims. The opponent preferred the Delnorth Pty Ltd v Dura-Post (Aust) Pty Ltd decision, [2008] FCA 1225, 78 IPR 463. Gyles J in that decision at [20] quoted Buckley LJ in Re Stauffer Chemical Co’s Application, [1977] RPC 33:-
“If a new feature were a development along the same line of thought which constitutes or underlies the invention described in the earlier document, it might be that that development could properly be regarded as fairly based on the matter disclosed in the earlier document … If, on the other hand, the additional feature involves a new inventive step or brings something new into the combination which represents a departure from the idea of the invention described in the earlier document, it could not, I think, be properly described as fairly based upon the earlier document.”
The descriptive text of the grandparent specification is substantially the same as that in the present application except that the grandparent specification does not have text corresponding with page 6 line 34 to page 8 line 8 as in the present specification. The drawings of the grandparent application are informal though they have the same content as in the present application. The above-mentioned passage, omitted from the grandparent specification, comprises consistory clauses broadly analogous with independent claims 1 and 21 and dependent claims 2-9. It is correct that some of this text relates to the cap, seal or encapsulation. However there are other sections consistent in both the grandparent specification and the present specification that appear to also discuss the cap, seal or encapsulation.
The opponent highlighted page 10 lines 16 and 17 of the grandparent specification. This passage states the outlet or outlets may be fitted with a rumen-erodable seal, cap, tape, encapsulation or equivalent. On the other hand the opponent suggested this was one isolated reference to these items in the whole specification akin to pointing against the ‘real’ disclosure when the grandparent specification is read as a whole and being “in truth only loose or stray remarks” (Lockwood at [69]). Moreover the opponent pointed out that even this passage did not describe the location of the additional dose in a cap, seal or encapsulation as claimed in claim 1.
With reference to Figure 1, page 14 line 26 to page 15 line 2 of the grandparent specification discusses the disposition in a reservoir 8 of an additional dose to exit via an outlet under the cap 7. The two outlets, for the first dose and the additional dose respectively, are at opposed ends of the barrel. While the reservoir may be said to be within the body of the device, it is also the case that the reservoir 8 is separate from the core tablet or matrices stack 5 in the body of the device and that the additional dose is under the cap 7. The cap 7 may thus be said to also overlay and contain the additional dose. This description provides sufficient basis for the second dose being located in a cap, etc, at the second end (item (iii) of claim 1).
Page 15 lines 9-14 particularly itemises the features of Figure 7. The additional dose 16 is on the outside, and optionally covered initially, in a sleeve member 17 which attaches to the barrel 18. While the remainder of the passage may be criticised for lack of clarity and consistency in its description of the features of Figure 7, particularly feature 18, the crux of the passage is reasonably clear. That is, that a sleeve member 17, which by definition in mechanical terms from the online Macquarie Dictionary, , may mean a tubular piece fitting over a rod or the like, is attached to the barrel 18 and overlays at least a portion of the barrel, and contains the additional dose. This would place the additional dose clearly outside the body of the device and in the case of Figure 7 is also located over the first outlet. This description provides sufficient basis for the second dose being located in a cap, seal or an encapsulation over the first outlet as at item (ii) of claim 1.

Figures 8A – 8D appear to more clearly describe all the claimed variants in claim 1 of the location of the second dose. The opponent argued those figures did not. For example, in respect to Figures 8C and 8D, the opponent argued the dump dose formulation unit 24 was an extended pocket within the body of the device, not a separate cap, etc. The applicant argued, with reference to page 15 line 19 of the grandparent specification, that the dump dose formulation unit being held in a pocket over outlet 23 meant the additional dose was external to the body of the device. Moreover, page 10 lines 10-15 of the grandparent specification discuss embodiments if additional space beyond the void space within the spring coils is required for the additional dose. One embodiment is described with the compartment of the barrel, which contains the continuous release formulation and the driving component, being truncated, and the component for the additional dose being added at either end of the principal formulation within the constraints of dose volume requirement and ease and safety of dosing. In the context of the specification as a whole, I favour the applicant’s view.
I conclude claim 1 in all its variants is fairly based on the grandparent specification so as to enable priority to be claimed at least from the date of filing of that specification.
The variants of claim 1 in respect to the location of the second dose at items (i) to (iv) may fall under section 43(3) of the Patents Act which enables a claim defining more than one form of an invention to have more than one priority date for each form of the invention. This situation was recently considered in both Nichia and AstraZeneca AB v Apotex Pty Ltd, [2014] FCAFC 99. Since I have determined that all variants of the present claim 1 are entitled to priority back to at least the grandparent application, I do not need to consider the applicability of section 43(3) further.
The NZ provisional specification has several differences compared to the grandparent specification. Notably the NZ application does not have Figures 8A – 8D and any associated description in respect to those figures. However the descriptive part of the NZ specification with reference to at least Figures 1 and 7, and the description of the additional dose in additional space beyond the void space within the spring coils (at page 11 of the NZ specification), as with the grandparent specification, is sufficient to provide the necessary fair basis for claim 1 to be entitled to its earliest priority date.
I conclude the claims of the present application are entitled to the earliest priority date from the NZ application.
Novelty
It is well established that the general test for lack of novelty is the reverse infringement test. The classic formulation of this test is that given by Aickin J in Meyers Taylor Pty Ltd v Vicarr Industries Ltd, [1977] HCA 19 at [20], 137 CLR 228, at 235:
“The basic test for anticipation or want of novelty is the same as that for infringement and generally one can properly ask oneself whether the alleged anticipation would, if the patent were valid, constitute an infringement”.
This test is satisfied if the alleged anticipation discloses all the essential features of the invention as claimed (see Nicaro Holdings Pty Ltd v Martin Engineering Co, [1990] FCA 40, (1990) 91 ALR 513 at 517). In order to meet this requirement, the prior art must "contain clear and unmistakeable directions to do what the patentee claims to have invented" (The General Tire & Rubber Company v The Firestone Tyre and Rubber Company Limited, [1972] RPC 457 at 486).
In submissions and at the hearing the opponent relied only on the publication of the applicant’s grandparent application 2005209631 as a basis for lack of novelty. This was on the assertion that the present claims were not entitled to an earlier priority date.
Since I have determined the claims are entitled to their earliest priority date, the grandparent application cannot anticipate the claims. Even if I were wrong about the priority date, I would note that a similar argument came before Yates J in Vehicle Monitoring Systems Pty Ltd v Sarb Management Group Pty Ltd (No. 2), [2013] FCA 395. At [210], Yates J stated:-
“…the respondent specifically advanced the parent specification as an anticipatory disclosure of the invention as claimed in all claims. … But if the disclosures in the parent specification anticipate the invention as claimed (as the respondent contended), the claims must at least pass the threshold of being fairly based on matter disclosed in the parent specification, in the sense that there must be a real and reasonably clear disclosure of the invention as claimed. I reject the respondent’s contrary submission. It can be seen, therefore, that the respondent’s challenge to validity, based on the prior publication of the parent specification, is self-defeating because that challenge provides an undeniable foundation for finding that the priority date of the claims is not the deferred date.”
At [211] Yates J indicated the same self-defeating argument applied in respect to the grandparent specification and the provisional specification in that case.
I conclude the present claims are novel in this case.
Inventive Step
Subsection 7(2) of the Patents Act states that an invention is taken to involve an inventive step unless it would have been obvious to a person skilled in the art in the light of the common general knowledge, considered alone or together with the prior art. A document is prior art for this purpose if "a skilled person mentioned in subsection (2) could, before the priority date of the relevant claim, be reasonably expected to have ascertained, understood, regarded [the document] as relevant" (Subsection 7(3) at the relevant time).
The test for whether an invention is obvious is whether it would have been a matter of routine to proceed to the claimed invention. In Wellcome Foundation Ltd v VR Laboratories (Aust.) Pty Ltd, [1981] HCA 12 at [45], 148 CLR 262 at 286, Aickin J stated:
"The test is whether the hypothetical addressee faced with the same problem would have taken as a matter of routine whatever steps might have led from the prior art to the invention, whether they be the steps of the inventor or not."
The High Court in Aktiebolaget Hässle v Alphapharm Pty Ltd, [2002] HCA 59, (2002) 56 IPR 129 at [50] – [53], appeared to approve of the Wellcome test. In discussing what was meant by a matter of routine the High Court noted and accepted an affinity with the approach in Olin Mathieson Chemical Corporation v Biorex Laboratories Ltd, (1970) 87 RPC 157, of whether the person skilled in the art would directly be led as a matter of course to try what was claimed in the expectation that it might well produce a useful alternative. In Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [No. 2], [2007] HCA 21, (2007) 235 ALR 202, general principles regarded to be of continuing relevance, at [50] – [52], were that “obvious” means “very plain”, a scintilla of invention remains sufficient to support the validity of a patent, there must be some difficulty overcome, some barrier to be crossed, and an invention must be beyond the skill of the calling.
In AstraZeneca at [202] and [203], the court found that if a problem addressed by a patent specification is itself common general knowledge, or if knowledge of the problem is part of the prior art information (Subsection 7(3)), then such knowledge or information will be attributed to the hypothetical person skilled in the art for the purpose of assessing obviousness. On the other hand, if the problem cannot be attributed to the hypothetical person skilled in the art in either of these ways then it is not permissible to attribute a knowledge of the problem on the basis of the inventor’s “starting point” such as might be gleaned from a reading of the complete specification as a whole.
Person Skilled in the Art
The opponent indicated the person skilled in the art in the present case was a person skilled in the area of IRDDs, release profiles and compositions, including anthelmintic formulations, for the control and treatment of diseases in ruminant animals. The opponent nominated two of its declarants, Dr Page and Dr Ellis, as clearly suitable persons skilled in the art in this case.
The applicant indicated the person skilled in the art was one experienced in veterinary science for production animals and in the design or use of IRDDs for such animals. The applicant submitted that each of its expert witnesses were skilled addressees.
Both parties would appear to be correct to varying extents in their characterisation of the appropriate person skilled in the art. The specification as a whole relates to IRDDs primarily for the delivery of anthelmintics to ruminant animals. I would characterise the person skilled in the art as one experienced in the design and use of various types of IRDDs, and the use of various release profiles and formulations from such devices for ruminant animals. The parties expressed preferences for particular declarants’ evidence to be weighted more heavily over those of some other declarants in this opposition. In the light of my characterisation of the person skilled in the art in this case, I will determine the appropriate weighting of evidence where necessary later in this decision.
The Nature of the Problem
Elements of the evidence and discussion at the hearing focused on the nature of the problem existing in the art at the relevant time. The opponent submitted the problem solved by the invention is the provision of an IRDD having both dump dosing and sustained dosing options located in the device. On the other hand, I fail to see a problem in this statement. A development is mentioned of having dump doses and sustained doses in the same device, rather than what issues or problems existed in the art that may have led to this development. The opponent’s description of the problem draws in the type of ex post facto analysis the courts have often warned against. See for example Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd, (1980) 144 CLR 253.
The opponent’s declarants also appeared to have the above statement put to them as the problem when preparing their evidence (for example Ellis at [20], Lichti at [16], and Page second declaration at [9] and [10]). The evidence on inventive step from these declarants must consequently be treated with some caution.
As mentioned earlier, the specification contains extensive background on the development of IRDDs. The specification discusses the known problem of resistant worm populations and the incorporation of priming or dump doses in devices such as the Laby device to combat that problem. A resultant problem with priming or dump doses then was that the rapidly dissolving formulations could break the moisture seal otherwise provided by spring-loading the tablets against the opening of the device.
On the other hand, the AstraZeneca case, as discussed above, suggests this approach to identifying the problem has also gone too far. One is permitted only to attribute knowledge of the problem to the person skilled in the art if the problem itself were common general knowledge, or the problem were part of the prior art information (Subsection 7(3)).
The applicant’s declarants described the existing problem in the art, at the relevant time, as the resistance of worm populations to animal treatments. Dr Steel at [48] stated that it was well known by the relevant time that resistance was an issue and one way to deal with resistance was to use combination drench products. Mr Venning at [23] stated an important problem was increasing parasite resistance to anthelmintics. I agree with the applicant’s description. I conclude the problem of parasitic resistance to anthelmintics was common general knowledge at the relevant time.
In respect to the prior art information, the examples in evidence in respect to Laby devices discussed the above resistance problem, variable dissolution rates of actives, the sealing problems with inconsistent release profiles, the problems of toxicity and prolonged altered physiological states with continuous, sustained releases, and the incorrect opening of the wings. The prior art relating to osmotic devices, produced in evidence, essentially discussed the problems of start-up time for the continuous, sustained release, and inconsistent release profiles. I will assess inventive step in this case in the light of the immediate problems identified above with the respective devices.
Common General Knowledge
The opponent referred to Dr Page’s first declaration to summarise the common general knowledge at the priority date. Primer or loading dose options in combination with sustained dosing options were used to treat ruminants. IRDDs included osmotic drive systems, for example Alza devices, and spring-driven bolus/tablet systems, for example Laby devices. Osmotic drive systems provided primer and sustained dosing options located within the same device. Laby devices contained a body, substantially impervious to rumen fluids, with a barrel having a bolus or tablets biased to an outlet at one end of the device for contacting the bolus or outermost tablet to rumen fluid, and a variable geometry, winged, system for retaining the device in the rumen. Commercially available Laby devices in Australia provided sustained dosing options from a stack of tablets housed in the devices for the delivery of multiple active agents.
The applicant disputed that the above was common general knowledge at the priority date. For instance, rather than primer and sustained dosing options being located within the same device, the applicant stated that it was commonly known at the relevant time to provide the primer dose as an oral drench combined with the use of the IRDD for the sustained dose. With reference to Dr Steel’s evidence at [65], the applicant submitted the following was common general knowledge.
There were a range of different IRDDs that had been used commercially and most people would have been aware of the Laby device, the older erodible devices, reservoir systems and matrix systems, and osmotic devices. The way these devices worked would also have been common general knowledge. In respect to osmotic devices, they used density for retention and were known to have a lag period between administration and actual delivery of the drug. In respect to the Laby device, people would have been aware that it worked by extruding a bioactive containing gel out of an orifice, and was retained by deployable wings. The use of oral drenches, including drenches containing multiple actives, was commonly known to combat resistance to anthelmintics and rid the animal of its parasitic load.
In some of the evidence and at the hearing, the applicant appeared to treat the various types of IRDDs and the various dosing options in isolation stating that persons skilled in the field would not have looked amongst different types of IRDDs when faced with problems with a particular type of IRDD. The applicant stated the operating principles of the different types, for example osmotic devices and Laby devices, were quite different. Osmotic devices generally had semi-permeable membranes, which allowed the ingress of rumen fluids to cause hydrogels or similar gels within the device to expand, thus driving the active(s) from the device through the exit orifice. On the other hand, the literature in this field at the relevant time appeared to be replete with individual articles discussing multiple types of IRDDs (Exhibits SWP 3-5 of Dr Page’s first declaration). For example, SWP-5 compared erodible systems, reservoir systems, dispersed matrix systems, osmotic systems and pulsatile systems. Within the section on erodible systems, Dr Laby’s work is traced from when he first advocated the use of polymeric wings for rumen retention of IRDDs in the early 1970s (referencing US Patent 3844285 (1974)). The Laby device of that time had a body portion formed of a cylinder with hemispherical wings pivotally attached along and adjacent the side of the cylinder prior to delivery to the rumen and expandable after delivery. Erodible devices were generally density devices, meaning they were retained in the rumen by a density element. The Laby device may also have been classed as an erodible system as the spring forced an erodible composition to extrude from the opening at one end of the device (Steel at [31]). Contrary to most earlier erodible devices though, the Laby device thus had a means to control the surface area of the device that was exposed to the rumen contents and strictly control the release rate. By 1985, Dr Laby had developed the Laby device to the form illustrated in Figure 5 of SWP-5 where the wing structure was of the same basic design at one end of the device as in the present application. Dr Laby’s analysis (1987) of the causes of wide variability in degradation rates of erodible devices in general is also acknowledged in this section of SWP-5. It is also noteworthy that the applicant’s Mr Chick stated, at [33], that the Laby device was a development from the earlier osmotic devices.
SWP-5 was published in 1997, that is seven years before the priority date of the present application, in Advanced Drug Delivery Reviews. The opponent’s Dr Page at [17] stated that Advanced Drug Delivery Reviews were one of several references that would have been commonly referred to by persons skilled in the field. SWP-3 is by the same author as for SWP-5 but published three years later in 2000. Much of the text is the same in parts of the two exhibits although SWP-3 contains amended and updated content compared to SWP-5. I think the appearance of a similar article to SWP-5 three years later and still four years before the priority date would add further weight that the contents of the two exhibits would have been commonly known by persons skilled in the field at the relevant time. In still further support of this proposition, the applicant’s Dr Steel at [25] has classified SWP 3-5 as essentially like handbooks, similar in function for example to a chemistry, biology or physics textbook. See for example ICI Chemicals & Polymers Ltd v Lubrizol Corp Inc, [1999] FCA 345, at [112].
I conclude on the above account that persons skilled in the art at the relevant time would have been well-versed across the range of available IRDDs and would have considered solutions available across the range of IRDDs when faced with problems with a particular type of IRDD. However this does not necessarily mean all combinations of features from the range of IRDDs would have been brought together by a person skilled in the art. In assessing inventive step, the law requires that it would have been obvious to a person skilled in the art to select the particular claimed combination. See for example Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd, [1980] HCA 9, (1980) 144 CLR 253. As mentioned earlier, the applicant noted the different operating principles between osmotic devices and Laby devices. The former released actives through an outlet due to the expansion of an expanding member within the device under the ingress of rumen fluids through a semi-permeable membrane. The latter released actives through a spring-driven tablet delivery system. There may have been aspects of these two types of IRDDs that would not have been seen as readily transferable from one to the other at the relevant time. I will return to this issue later.
I would further note though that the applicant’s own specification discusses the applicability of its alleged invention across multiple types of IRDDs. Page 2 line 12, page 3 lines 13-14, page 5 lines 11-16, page 8 line 12 and page 15 lines 15-17 all relate the alleged invention to both density and variable geometry devices for retention in the rumen. Moreover page 3 lines 3-8 refers to a device disclosed in a US patent for Alza Corporation. That particular device is an osmotic device.

In respect to dosing options, the evidence does not appear to clearly establish when before the priority date the use of primer or dump doses in combination with sustained doses from the same device became commonly known. Page 6 lines 15-19 of the specification appears to allude to an earlier example and problem with dump dosing and continuous, sustained dosing from the same device. However this does not necessarily mean that was common general knowledge at the relevant time (AstraZeneca at [202] and [203]). Osmotic devices were generally known initially for their inconsistent release profiles (Chick at [28]) and their lag period between administration of the device to the subject animal and the onset of agent delivery (Chick at [57]). An example of an osmotic system that had an initial burst effect of release of the drug before settling to a near constant release rate is mentioned in exhibit SWP-5 at page 318. While this disclosure may pertain to a solution for overcoming the lag problem, the exhibit does not appear to explicitly state the burst release was for this purpose. Mr Chick at [57] referred to three patent documents produced in evidence by the opponent of ways of overcoming the lag period of an osmotic device. All three disclosures offered solutions to the lag period by way of initial fast release mechanisms of a first active followed by continuous, sustained and slower release of a second active. However, firstly, the description of the fast release profile in these documents appears to be different to a dump dose as defined in the patent specification. Secondly one of the three patent documents refers to another of the three documents as not providing a satisfactory solution to the lag period. Thirdly, I regard the evidence as insufficient to establish that the contents of any of the three patent documents were common general knowledge at the relevant time. I agree with the applicant that, on the available evidence, it was merely common general knowledge at the relevant time to use an oral drench for the dump dose in combination with an IRDD for the continuous, sustained dose. I will return to the disclosures of the three patent documents later.
Both parties appeared to find it acceptable that the use of multiple actives in the same device was common general knowledge. The applicant acknowledged the use of oral drenches containing multiple actives being commonly known for combatting resistance to anthelmintics (for example Steel at [46] – [49]). The opponent suggested commercially available Laby devices provided for the delivery of multiple actives from the tablet stack. SWP-5 at page 307 mentions extensive work from the basic design of the Laby device in patent literature, from 1983 to 1996, which describes improvements in delivery of multiple drugs with a single device, amongst other improvements. In recalling that SWP-5 was published in Advanced Drug Delivery Reviews in 1997, I am prepared to accept the delivery of multiple actives by a Laby device was commonly known before the priority date.
In the light of the above, I regard the following to have been common general knowledge before the priority date of the present application. Persons skilled in the art would have commonly known and understood the range of types of IRDDs available such as erodible systems, reservoir systems, dispersed matrix systems, osmotic devices, and particularly Laby devices. The Laby device worked by a spring biasing tablets towards the orifice at one end of the device and was a variable geometry, winged device. Moreover, these persons would have had regard to available solutions amongst the different types of IRDDs when faced with problems with any particular type of IRDD. However, this would have been subject to it being obvious to select specific features of different types of IRDDs and provide the claimed combination. Primer doses involving oral drenches in combination with continuous, sustained doses from IRDDs were also common general knowledge, as were the use of multiple actives in the same device.
Whether There is an Inventive Step
Common General Knowledge Alone
In the light of my conclusions above on common general knowledge, claim 1 of the application clearly defines additional features, notably at least the juxtaposition of the second dose in the same device. Claim 21 defines the additional features of at least the release of the dump dose exposing the outlet of the body and the subsequent continuous dose delivery of a second active from the same IRDD.
I conclude the claimed invention has an inventive step when considered in the light of the common general knowledge alone.
Inventive Step in Light of Prior Art Documents
At the relevant time, subsection 7(3) restricted prior art information used to support lack of inventive step to that which the person skilled in the art could be reasonably expected to have ascertained, understood and regarded as relevant.
Dr Page, at [30] of his first declaration, mentioned the practice of persons skilled in the art to search existing literature, including patent databases. Dr Ellis at [19] and [20] mentioned his practice, and that of CSIRO, of routinely watching for and consulting patent documents associated with rumen technology. SWP-3 and SWP-5 also reference numerous US patents when describing improvements in Laby devices before the priority date. SWP-4 contains a Section 7 titled “Patented and marketed ruminal drug delivery devices”. I am satisfied a person skilled in the present art could reasonably be expected to have ascertained, understood and regarded as relevant the patent literature relating to IRDDs at the relevant time.
Of the alleged prior art listed in the amended statement of grounds and particulars, the opponent pursued only the following documents at the hearing:-
D4: WO 2003/033031, Eli Lilly & Company
D6: US 5,240,713, Ayer (and assigned to Alza Corporation)
D7: WO 1991/010423, Alza Corporation
D11: US 4,643,731, Eckenhoff (and assigned to Alza Corporation)
D4: WO 2003/033031
D4 relates to a controlled dosage release element adapted for insertion and retention in the rumen of a ruminant animal. The element comprises a winged, variable geometry device. The element further comprises one or more discrete amounts of a first active agent adapted to dissolve in rumen fluids such that short or pulsed episodes of release of the agent occurs, and one or more amounts of a second active agent adapted to dissolve in rumen fluids at a sustained, controlled rate. The first actives are interspersed at predetermined locations with the second actives within the element. One example has the actives provided as separately tabletted forms. Another example has the actives prepared in dual formulation tablets. A third example, modified from the second, has the pulsed-release active placed in a shallow well in a tablet of the controlled-release active.
In respect to claim 1 of the present application, D4 does not disclose the location of any dose in a pocket in the body of the device, or in a cap, seal or encapsulation. The opponent submitted, with the evidence of Dr Page for example at [156], that this feature merely claimed all possible locations where the second dose may be located. On the other hand, this submission appears to reflect the opponent’s enunciation of the problem as the provision of an IRDD having both dump dosing and sustained dosing options located in the device. If the problems at the relevant time were more correctly put broadly as the increasing resistance of parasites to anthelmintics, or as the problems acknowledged in the prior art with Laby devices, as discussed above, one must wonder what the motivation would have been to specifically provide a second dose, let alone to locate it in certain places associated with the IRDD. The applicant particularly noted the main alternative solutions contemplated at the relevant time were alternate tablet formulations and more sophisticated formulation development, as shown for example by D4, and Mr Chick at [27] and Dr Steel at [61].
In respect to claim 21, a dump dose release profile appears to be disclosed in D4. The paragraph bridging pages 3 and 4 of D4 describes the release of the first active as short episodes of a matter of minutes to hours. Page 12 of the present specification defines dump doses as commencing release within one hour of dosing with dosing being essentially completed within 12 hours. However there are differences between claim 21 and D4. Firstly D4 does not disclose the exposure of the outlet of the body being dependent on the dump dose release of an active. Secondly D4 describes the release of the first active from a rapidly disintegrating formulation with a pulsed release profile. Page 2 of D4 describes the aim being to deliver one or more discrete episodes of an active at one or more predetermined times. On the other hand, claim 21 defines the release of the second agent in sequence after the release of the first agent. D4’s pulsed release profile of the first active, interspersed with continuous release of the second active, does not disclose the dump-dose release profile followed by the continuous release of a second active as claimed in claim 21 of the application. I find the person skilled in the art would not directly have been led as a matter of course from D4 to try the invention as claimed. I conclude the claims have an inventive step over D4.
D6: US 5,240,713
D6 relates to an osmotic IRDD. In this respect, I would firstly note that the majority of the claims of the application generally are not necessarily restricted to a spring-driven stacked tablet IRDD of the Laby type. Claim 1 of the application appears to exclude osmotic devices though by defining the elongate body as being substantially impervious to rumen fluids. On the other hand, claim 21 does not have any such limitation. An osmotic drive for releasing the agents from the device is not excluded from the scope of claim 21.
In D6, an expandable driving member within the device is responsive to the ingress of rumen fluid through the semi-permeable wall of the device to expand and thereby assist in expelling a first active from the device. The first active is expelled at a fast rate. The fast rate is achieved by the outlet of the device being of sufficient size to provide for immediate initiation of delivery of the first active by diffusion or erosion of the active formulation on contact with rumen fluids in conjunction with the expansion of the expandable driving member. Subsequently a second agent is delivered from the device at a controlled and uniform rate by the driving member. Embodiments of the second agent include tabletted, formulation layers within the device. A slideable partition within the device, and with a plurality of apertures, provides separation of the first and second actives. As the expandable driving member expands in use, the partition is pushed towards the lead end of the device to assist in expelling the first active. Further expansion of the expandable driving member expels the second active through the exits in the partition and through the outlet of the device.
In respect to claim 1 of the application, D6 does not disclose a body substantially impervious to rumen fluids. On the contrary, the device is semi-permeable to function as an osmotic device. The motivation for the person skilled in the art to have altered the drive mechanism of D6 from osmotic to a substantially impervious device driven by some other means is not clear from the evidence in this case. D6 also does not disclose a variable geometry device. Instead, the device of D6 is retained in the body of the animal by a density element. On these two features, I would regard claim 1 as having an inventive step over D6.
Claim 21 does not necessarily exclude osmotic drives but is limited to at least one variable geometry device dependent from body of the device. Consequently I should determine whether it would have been obvious at the relevant time to replace the density element in the osmotic device of D6 with a variable geometry device dependent from the osmotic device. The evidence indicates that osmotic devices, at least before the priority date, were generally equipped with a density element therein as the means of rumen retention. The density element was clearly a mechanism internal to the device whilst the variable geometry device was external of the IRDD. Moreover, since the osmotic device relied on the ingress of rumen fluid through the semi-permeable membrane for its proper function, it would appear that any impediment, actual or potential, to the flow of rumen fluid through the membrane should be avoided. This factor would seem to teach away from the placement of a variable geometry device external of an osmotic IRDD. The opponent has not presented evidence of variable geometry, osmotic IRDDs before the priority date, or evidence that such a step would have been a matter of routine for the person skilled in the art. On this point, I would regard claim 21 as having an inventive step over D6.
Even if I were wrong on the above analysis, I further note the separation of the actives in D6 is with a slideable partition. The opponent suggested, in respect to claim 1, that this formed a pocket in the body of the device for the first active. The online Macquarie Dictionary defines a pocket as a bag or pouch, or any pouch-like receptacle, hollow or cavity. On the other hand, the slideable partition merely separates the two actives into separate chambers within the device. I think it could not be fairly said that D6 discloses a pocket in which an active is located. The opponent alternatively suggested that the compartment in D6 containing the first active could be considered an encapsulation located over the exits within the slideable partition, through which the second active subsequently extrudes. The Macquarie Dictionary defines an encapsulation as the enclosure of one thing within another thing. I think it could not be fairly said that the partitioning of a device into two separate chambers was equivalent to an encapsulation. In respect to claim 21 of the application, D6 discloses the release of the first active followed by the second active. The release profile of the first active though is of immediate and continued delivery of active agent during the period required for the expandable driving member to become fully activated (D6, column 7 lines 46-51). The “start-up” period of the expandable driving member is usually at least several days and often up to several weeks (column 7 lines 19-25). As mentioned earlier though, the present specification states that dump doses are defined as commencing release within one hour of dosing with dosing being essentially completed within 12 hours. I find that D6 does not disclose the release of an active with a dump dose release profile as claimed in claim 21 of the application.
Overall I find the person skilled in the art would not directly have been led as a matter of course from D6 to try the invention as claimed. I conclude the claims have an inventive step over D6.
D7: WO 1991/010423
D7 also relates to an osmotic device and also operates to deliver a first active at a rapid rate followed by a second active at a continuous, controlled rate. The fast active is initially retained in a loading dose compartment within the IRDD. The paragraph bridging pages 12 and 13 of D7 contemplates various locations for positioning the loading dose compartment. The figures of D7 clearly illustrate the loading dose compartment 30 being a small segregated section in the body 12 of the device. In respect to claim 1 of the application, I would regard this as equivalent to a pocket, holding an active, in the body of the device.
The principal difference between D7 and the claims of the application is the definition in the latter of the device being a variable geometry device. I have earlier regarded the claiming of the variable geometry feature as having an inventive step over the device of D6. The same would apply in respect to D7.
Furthermore, in respect to claim 21, the first active is described throughout D7 as a loading dose. This may suggest it has a dump dose release profile. On the other hand, the release profile of the first active is of rapid and continuous delivery during the start-up period of the long-term delivery aspects of the device. The delivery of the loading dose is designed to mesh closely with the delivery rate of the second agent, once the start-up period has elapsed, so that delivery is as uninterrupted and continuous as possible (D7, page 5 lines 5-15). The situation appears to be similar to D6. I find that D7 does not disclose the release of an active with a dump dose release profile as claimed in claim 21 of the application.
I find the person skilled in the art would not directly have been led as a matter of course from D7 to try the invention as claimed. I conclude the claims have an inventive step over D7.
D11: US 4,643,731
D11 describes an osmotic dispensing system comprising a dispensing device and a cap. Within the dispensing device is a first active. The cap surrounds one end of the dispensing device and also retains a second active. The cap is dissolved on contact with rumen fluid to first release the loading dose, that is, the second active. This exposes the opening of the main dispensing device to release the continuous dose, that is, the first active, from the opening.
As for D6 and D7, the principal difference between D11 and the claims of the application is the definition in the latter of the device being a variable geometry device. I have earlier regarded the claiming of the variable geometry feature as having an inventive step over the device of D6 and D7. The same would apply in respect to D11.
In one respect, D11 highlights the difficulty with the opponent’s contention that it would have been obvious to combine the features of an osmotic device with the features of a Laby device, such as the winged, variable geometry feature. In respect to claim 1, D11 appears to be the closest prior art in terms of having a cap or encapsulation, that holds an active, at one end of the device. A density member is also within the device at the same end. The wall of the cap member loses its integrity quickly on administration thereby releasing the active within the cap immediately. The wall of the osmotic device per se is semi-permeable, driving the osmotic function of the device. In this context, it appears difficult to envisage where a variable geometry feature would have been placed on an osmotic device whilst also preventing interference with its proper functioning. Similarly the motivation to have altered the drive mechanism of D11 from osmotic to a substantially impervious device with a cap and a spring drive, for example, is not clear from the evidence in this case.
In respect to claim 21, D11 describes the object of providing a dispensing device possessing instant agent availability during the start-up period before the sustained, continuous agent delivery begins (column 2 lines 21-26). While D11 describes the instant agent availability as a burst of agent and an agent-pulse release, the coverage of this release over the start-up period is outside the definition of a dump dose, as already mentioned above.
I find the person skilled in the art would not directly have been led as a matter of course from D11 to try the invention as claimed. I conclude the claims have an inventive step over D11.
Other Grounds of Opposition
In evidence and at the hearing, the opponent did not press the remaining grounds of opposition as enunciated in its statement of grounds and particulars. Having reviewed the specification, the evidence and those grounds and particulars, I am satisfied there is nothing further of substance amongst those items that would affect the validity of a patent if granted.
Conclusion

I conclude the opponent has been unsuccessful on its grounds of opposition against the patent application.
Subject to appeal, I direct the application proceed to grant.
Costs
Both parties sought their costs in this case. I see no reason to depart from the normal practice that costs follow the event. I award costs in accordance with Schedule 8 against the opponent, Merial Limited.
M. G. Kraefft
Delegate of the Commissioner of Patents