The American National Red Cross, the United States of America as Represented by the Secretary of the Army and Loyola State University of Chicago v Baxter Healthcare Corporation
[2002] APO 49
•18 December 2002
OFFICIAL NOTICE
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Application : No. 696691 in the name of The American National Red Cross, The United States of America as represented by The Secretary of the Army and Loyola State University of Chicago
Title: Supplemented and unsupplemented tissue sealants, methods of their production and use.
Action: Opposition under section 59 of the Patents Act 1990 by Baxter Healthcare Corporation
Decision: Issued .
Abstract
The invention as claimed is predicated on the applicant's discovery that there is prolonged delivery of a drug from fibrin glue when the drug is loaded in an amount in excess of the drug's solubility in the fibrin glue. The claims define fibrin glue supplemented with a solid drug wherein the drug is loaded in an amount that is greater than the amount of the drug that is soluble in the fibrin glue.
The opposition failed on the grounds of full description, novelty, inventive step and manner of manufacture. Although it also failed on the ground of clarity of claims 1-26, claim 27 was found to lack clarity.
Costs were awarded against the applicant up to 14 February 2001: the date at which the specification was substantially amended, and against the opponent after this date.
PATENTS ACT 1990
DECISION OF A DELEGATE OF THE COMMISSIONER OF PATENTS
Re:Patent Application No. 696691 by The American National Red Cross, The United States of America as represented by The Secretary of the Army and Loyola State University of Chicago and opposition under section 59 of the Patents Act 1990 by Baxter Healthcare Corporation.
BACKGROUND
Patent application 696691 (63648/94) in the name of The American National Red Cross et al (hereafter referred to as ARC) was filed as PCT application PCT/US94/02708 on 14 March 1994 claiming priority from US 08/031 164, which was filed on 12 March 1993. The application was advertised as accepted on 17 September 1998. Baxter Healthcare Corporation (hereafter referred to as Baxter) filed a notice of opposition on 17 December 1998 and served their statement of grounds and particulars on 17 March 1999. Service of evidence in support was completed on 17 January 2000.
ARC requested leave to amend the specification on 17 July 2000. The amendments were allowed on 12 February 2001.
Evidence in answer was served on 13 November 2001 and evidence in reply was served on 31 May 2002.
The matter was heard in Canberra on Tuesday 3 September 2002. ARC was represented by Mr Mark Roberts, Patent Attorney of Davies Collison Cave, Melbourne, and Baxter by Dr Ken Finney, Patent Attorney of Cullen & Co, Brisbane.
THE EVIDENCE
The evidence in support consists of:
Statutory Declaration of Desmond B Williams (W1), pharmacist and chemist, made 13 January 2000, together with exhibits DBW-1 to DBW-15.
The evidence in answer consists of:
Statutory Declaration of Jerry Kanellos (K), scientist with Commonwealth Serum Laboratories, made 12 November 2001, together with exhibits JK-1 and JK-2.
Statutory Declaration of Stanley A Friedman (F), scientist with ARC, made 7 November 2001 together with exhibits SAF-1 to SAF-5.
The evidence in reply consists of:
Statutory Declaration of Kenneth G Finney, patent attorney of Cullen & Co, made 29 May 2002, together with exhibits KGF-1 to KGF-10.
A second Statutory Declaration of Desmond B Williams (W2), made 29 May 2002.
KGF 2-10 are 9 journal articles that are additional to the documents filed by ARC with the evidence in support.
THE SPECIFICATION
The specification is that as amended after acceptance. It is directed to supplemented and unsupplemented tissue sealants, with fibrin glue (FG) disclosed as a preferred tissue sealant.
10. Tissue sealants are used to reduce blood loss and maintain haemostasis of internal and external wounds. FG is a preferred tissue sealant because it forms a gel similar to a natural clot. There are a number of commercially available FG preparations and the specification discloses that at the priority date of the application it was known to supplement FG with growth factors and drugs to provide improved wound repair and localised drug delivery. It also discloses that these preparations did not provide controlled or sustained release of the supplement from the gel and that there was a need in the art for a method of extending the duration of drug release from the tissue sealants (page 13).
11. Examples 12 and 16 disclose prolonged delivery when FG is supplemented with solid drugs. In particular figure 30, which relates to example 16, discloses prolonged delivery when a drug is loaded in an amount that is in excess of the solubility of the drug in the FG in contrast to when the drug is simply loaded in solid form.
THE CLAIMS
12. Claim 1 recites:
A supplemented tissue sealant comprising fibrin glue and a drug, wherein said drug is present in said tissue sealant in solid form in an amount greater than an amount of said drug which is soluble in said tissue sealant.
13. There are a total of 27 claims in the specification with two further independent claims, claims 11 and 20.
Claim 11
A process for localised deliver of a drug to a tissue comprising applying to said tissue a supplemented tissue sealant comprising fibrin glue and a drug, wherein said drug is present in said tissue sealant in solid form in an amount greater than an amount of said drug which is soluble in said tissue sealant.
Claim 20
A process for producing a supplemented tissue sealant comprising mixing drug with fibrin glue before fibrin glue forms a fibrin matrix, wherein said drug is present in said tissue sealant in solid form in an amount greater than an amount of said drug which is soluble in said tissue sealant.
14. The claims contain a number of technical terms and features whose definition is important for a full understanding of the scope of the claims.
15. The specific tissue sealant that is the subject of the claims is FG. FG is a hydrated gel formed when fibrinogen and thrombin are mixed in the presence of calcium ions. This means that the claimed composition comprises at least a fibrin matrix, a drug and a solvent. Thus, when calculating the amount of drug in the claimed FG, the calculations must take into account not only the volume of the fibrin matrix but also the volume of solvent in the matrix and the solubility of the drug in the solvent.
16. It is also worth noting that the key to the invention is the feature that is inherently provided by loading a drug in FG "in solid form in an amount greater than an amount of said drug which is soluble in said tissue sealant". This feature is the release kinetics that result when a drug is loaded in this amount. These release kinetics are quite different to the release kinetics for the same drug loaded in FG below its solubility limit and it is this form of release that produces prolonged delivery of a drug to a tissue over an extended period of time.
17. Thus the claimed compositions do not simply provide a somewhat extended period of release because they provide more drug, or more drug in solid form. They provide a different profile of release that significantly extends the duration of drug release and that is quite distinct from the release profile seen when the same drug is loaded below its solubility limit.
THE DECISION
Novelty
18. Baxter chose not to present oral submissions with respect to novelty at the hearing and elected to rely on the written submissions that they provided at the hearing and a restricted number of the documents in their earlier submissions. Dr Finney confirmed that, as a consequence of the amendments, there were now only two documents that were directly relevant to novelty, GB 2102811, published 9 February 1983 and AU 576365, published 4 December 1985.
19. An essential feature of the invention as claimed is that the drug is present in an amount that is in excess of the amount of the drug that is soluble in the FG. Thus, when assessing the prior art it is important to consider whether or not the prior art clearly and unmistakably discloses FG supplemented with a drug loaded in excess of its solubility. Disclosure of solid and solid, barely soluble drugs in FG at amounts that are not clearly in excess of their solubility, or disclosure of a broad and indeterminate range of drug amounts cannot necessarily be regarded as anticipation of the invention as claimed.
20. As stated in General Tyre & Rubber Co v Firestone Tyre & Rubber Co Ltd, (1972) RPC 457:
"To anticipate the patentees claim, the prior publication must contain clear and unmistakable directions to do what the patentee claims to have invented….. A signpost, however clear, upon the road to the patentee's invention will not suffice."
21. UK 2102811 discloses fibrin glues supplemented with antibiotics. At page 1, lines 50-55, there is a discussion of supplementation with "hardly soluble" antibiotics and recognition that this will cause lasting efficacy. The examples describe preparation of FG supplemented with solid gentamycin and cephalosporanic acid.
22. AU 576365 discloses FG supplemented with drugs in solid and liquid forms in amounts varying from 0.1% to 50% in weight (page 8). It also discloses various techniques for diminishing drug migration including varying the solubility of the drug (page 6).
23. As such both citations clearly disclose FG supplemented with solid drugs and both recognise the advantages of providing drugs in poorly soluble form. However, the general disclosure of FGs supplemented with solid drugs, albeit hardly soluble drugs, is not a clear disclosure of FGs supplemented with solid drugs in an amount in excess of their solubility. Although the general disclosure may include FGs supplemented with drugs loaded in excess of their solubility, to deprive the claims of novelty the disclosure must provide clear directions that direct the skilled worker toward the specific section of the range that provides drugs in excess of their solubility.
24. There are no clear directions in the general discussions in either of the two citations with respect to loading drugs in FG in amounts in excess of their solubility in the FG. In particular, none of the examples in either citation clearly discloses supplementation of FG with a drug in an amount that is in excess of the amount of the drug that is soluble in the FG.
25. Although example 4 of UK 2102811 discloses sustained release when solid cephalosporanic acid is added to FG, there is insufficient information in the example with respect to buffers, drug amounts or FG amounts to determine whether the amount of drug loaded is an amount that is in excess of the solubility of the drug in the FG. There is also no suggestion that the drug is loaded in an amount that is in excess of its solubility or that this form of loading will provide improved release kinetics.
26. Furthermore, it cannot be inferred that, because the citation discloses sustained release, the release must follow the same order kinetics seen by the applicant and must therefore be a consequence of loading a drug in excess of the drug's solubility in FG. This inference cannot be made because the methodology used in the citation for assaying release kinetics is not comparable to the methodology used by the applicant.
27. Dr Friedman explained that, by his calculations, the method of the citation uses a 1:1 ratio of drug-supplemented FG to buffer. He described this as "limited sink" methodology, where the rate of diffusion of the drug out of the FG is limited by the amount of buffer around the sealant (F 12.1-2). This is in contrast to the applicant's method that uses a 1:10 ratio of FG to buffer to avoid restricted diffusion rates as a result of limited buffer volumes. Thus, the kinetics of drug release seen in the citation are not comparable to the kinetics demonstrated by the applicant.
28. As such, it cannot be inferred that, because the citation discloses sustained release, the citation must therefore disclose a drug loaded in FG in an amount that is in excess of the drug's solubility in the FG.
29. Dr Williams also raised the point that AU 576365 disclosed 5-FU supplemented at 18 mg/ml (page 20), which is in excess of the 17 mg/ml exemplified in the opposed application, and thus would be assumed to be in excess of its solubility in FG. However Mr Roberts submitted that different solvents, pHs and relative amounts of thrombin will all affect the solubility of a drug in FG and that it could not be assumed that 18 mg/ml was an amount that was in excess of the solubility of FG in that particular matrix preparation. He pointed out that there were clear differences between the experimental conditions in AU 576365 and those in ARC's examples. In particular in respect to the use of saline as a solvent in AU 576365.
30. Thus, as with the example in UK 2102811, AU 576365 does not clearly disclose a drug loaded in excess of the drug's solubility, or provide sufficient directions such that the skilled addressee would inevitably produce the claimed compositions.
31. As such, I am satisfied that neither citation clearly discloses the invention as claimed and that as a consequence neither citation deprives the claims of novelty.
32. Baxter also presented the argument that any lyophilised fibrin preparation supplemented with a drug fell within the scope of the claims because, in the absence of solvent, any drug is necessarily present in excess of its solubility. However this argument is only valid if the term "fibrin glue" includes both hydrated and lyophilised fibrin preparations.
33. However, as discussed previously, the term FG relates to the gel or clot-like composition that is formed when fibrinogen and thrombin are activated in the presence of calcium ions and a hydrated gel is formed. Thus there is a clear distinction between the hydrated FG of the claims and lyophilised fibrin preparations.
34. Furthermore, when this issue was raised at the hearing both Mr Roberts and Dr Finney confirmed that they were of the understanding that the term FG did not include the lyophilised product and that it was restricted to hydrated fibrin gels or clots.
35. Dr Kanellos also defines FG as a hydrated gel, stating that FG is
"a material formed from fibrinogen concentrate, thrombin concentrate, calcium ions and possible other proteins, which when mixed with an hydrating agent will coagulate to form a clot" (K 19)
36. Dr Friedman too treats tissue sealants and lyophilised preparations as different formulations and emphasises that there is a clear distinction between a solid drug in a lyophilised preparation and a solid drug in a tissue sealant.
"Also, the fact that a drug may precipitate out of solution when the supplemented material is lyophilized, only to go back into solution when it is rehydrated requires the drug to be "solid" only as a consequence of lyophilization. This is clearly not the same as a drug loaded above its solubility limit in the tissue sealant." (F 6)
37. As such, I am satisfied that it is clear that FG as claimed relates to hydrated fibrin preparations, as distinguished from lyophilised fibrin preparations and that this is consistent with the term as used in the art. Therefore I am also satisfied that the claims are novel in light of prior art disclosures of lyophilised fibrin preparations supplemented with solid drugs.
Inventive Step
38. At the hearing Dr Finney indicated that Baxter only wished to pursue the issue of inventive step in light of common general knowledge in the art.
39. There was agreement from both parties that the problem addressed by the applicant's specification was the problem of providing sustained release of a drug from a tissue sealant. Both parties also agreed that at the priority date of the application:
•FGs were well known,
•FGs could be supplemented with drugs, and
•FGs could be used for localised delivery of drugs.
40. There was also agreement that the solution offered by the claims was to include the drug in FG in an amount greater than the solubility of said drug in said FG, thus providing the advantageous release kinetics that lead to prolonged drug delivery.
41. The area of dissent between the two parties surrounded the issue of whether it was obvious to try the solution offered by the claimed invention. The crux of the matter being whether or not the skilled person would have predicted the modified release kinetics resulting from the addition of the drug at a concentration above its solubility.
42. Dr Williams declared that, at the priority date of the application, the skilled person would have had the expectation that drug release from FGs would have the same kinetics as drug release from other traditional matrices. He stated that it was well understood in the art that loading a drug in a solid matrix in excess of its solubility in that matrix when hydrated results in prolonged release and that a skilled person would have had the expectation that this would also occur with degradable, proteinaceous matrices such as FG.
43. Dr Williams supported this with a reference to Higuchi (1963) J. Pharm. Sci., 52(12), 1145-9, which was provided with the evidence in reply as KGF-2.
44. Higuchi discusses the kinetics of drug release from traditional inert matrices and refers to the sustained diffusion of a substance from a matrix when the substance is present in an amount that is in excess of the drug's solubility.
45. Dr Williams submitted that Higuchi represents common general knowledge in the art at the priority date of the application and supported this by reference to a number of other citations that all referred to Higuchi. These additional citations were either provided as exhibits KGF-3-10 or simply referenced in the declaration.
46. At the hearing ARC submitted that documents KGF2 to KGF10 should not be considered because they were not detailed in the statement of grounds and particulars. However, Dr Finney confirmed that all of the documents, save Higuchi (KGF-2) were simply included to demonstrate that the information disclosed in Higuchi represented common general knowledge in the art. Following this clarification ARC conceded that, given that they had prepared submissions in respect of Higuchi, it would be reasonable to address the issues raised in relation to this citation at the hearing and avoid any further delays.
47. Dr Williams argued that a skilled person would have been well aware of the kinetics disclosed in Higuchi and would have expected that the same release kinetics would apply when a drug was supplemented in FG.
48. However Higuchi deals with the release of drugs from inert matrices. This is in contrast to FG, which is not inert and is degraded in situ.
49. In addition, Higuchi explicitly acknowledges that the kinetics of release from degradable matrices or release in vivo may vary substantially from the release calculated in the citation.
"Actual dosage systems may be complicated by … (b) partial dissolution of the matrix substances." (page 1145) and "In real systems, however, a number of other factors may come into play which may modify the total behaviour. …. Other serious deviations from the derived relationship may occur for system which tend to differ significantly from the adopted models." (page 1149)
50. Thus it would appear that rather than supporting an expectation that all matrices will behave the same with respect to diffusion kinetics, common general knowledge in the art as exemplified by Higuchi supports an expectation that degradable matrices, such as FG, will behave differently to inert matrices.
51. Furthermore, Dr Williams himself concedes this in his second declaration, stating:
"Due to the complexities of the fibrin matrix, the release of drugs is not strictly according to the Higuchi relationship" (W2 3.9) and
"The kinetics for release described by Dr Friedman in his slide presentation do not follow the Higuchi model. This is not surprising as the Higuchi model requires the matrix to remain intact with minimal alteration in structure or composition. It is likely that the fibrin matrix will alter in structure and alter in size over the time used for delayed release of a drug included therein" (W2 4.19)
Dr Kanellos also submited that a person specifically skilled in the preparation and use of degradable, proteinaceous matrices would be well aware of the differences between such matrices and more traditional inert matrices and would expect that these differences would impact on the kinetics of drug release (K 25-26). He explained that unlike inert matrices proteinaceous matrices are subject to the action of proteolytic degradation and that prior to the applicant's invention there was the expectation that the rate of matrix degradation was independent of the rate of drug release. He submitted that there was the expectation that the rate of degradation would have an effect on the rate of drug release and that thus there was the expectation that this would result in release kinetics that were substantially different to those associated with inert matrices as discussed in Higuchi.
Giving regard to Higuchi's comments, Dr William's concession and Dr Kanellos' submissions and the lack of evidence to the contrary, I am satisfied that, at the priority date of the application, there was the expectation that the release kinetics from FG would differ from the release kinetics from traditional solid matrices. Furthermore, in light of both Dr William's and Dr Kanellos' comments I believe that there was the expectation that matrix degradation would potentially enhance the rate of drug release thus reducing the efficacy of FG as a medium for prolonged drug delivery.
As such I believe that it would not have been obvious to a skilled person at the priority date of the application that FG supplemented with a drug in excess of the drug's solubility in the FG would exhibit the release kinetics seen by the applicant, or that this form of supplementation would provide a solution to the problem of prolonged delivery. Thus, I find all of the claims inventive in light of common general knowledge in the art.
55. ARC also presented further arguments relating to the suitability of Baxter's expert witness Williams and to the long felt need for a tissue sealant that provided prolonged delivery. Although there may be merit in these arguments I do not believe that they add substantially to my finding in respect of inventive step and thus I do not believe there is any need to explore the matter in further detail.
Section 40 Matters
56. The opponent raised a number of section 40 issues relating to clarity, fair basis and full description. I will deal with each in turn.
(1) Claims 1-4, 11-13, 20-22, 26 and 27 are not clear because the term "drugs" is ambiguous.
57. Although both parties were in agreement in respect of the commonly understood definition of the term "drug" as "a chemical substance given with the intention of preventing or curing disease or otherwise enhancing the physical or mental welfare of humans or animals"(Macquarie Dictionary) Baxter suggested that this broad interpretation was inconsistent with the specification at pages 18 and 38. They argued that this inconsistency in the specification lead to a lack of clarity with respect to the scope of the claims.
58. The specification recites "growth factors, drugs, polyclonal and monoclonal antibodies and other compounds" and "drugs, other chemicals and proteins", which could suggest a narrower interpretation of the term that distinguishes between traditional small organic drugs and macromolecular drugs such as proteins.
59. However, I am satisfied that these statements are intended to elaborate the range of compounds suitable for use as supplements in FG and that they are not a suggestion that the scope of the term drug should be limited or distinguished from the dictionary definition. Consequently the plain meaning is appropriate and the scope of the term is clear.
(2) Claims 1-26 are not fairly based because the term "drugs" is too broad.
60. The test for fair basis is explained in Rehm Pty Ltd v Websters Security Systems (International) Pty Ltd 11 IPR 289
"The question is whether there is a real and reasonably clear disclosure in the body of the specification of what is then claimed, so that the alleged invention as claimed is broadly, that is to say in a general sense, described in the body of the specification."
61. Baxter submitted that the claims relating to FG compositions and the use of FG compositions lacked fair basis. They argued that the disclosure of prolonged delivery from FG supplemented with the small heterocyclic compound 5-FU did not provide a reasonable basis for claiming FG supplemented with all drugs, particularly drugs of substantially different chemical or physical composition, such as macromolecular compounds and peptides.
62. Although there is no requirement for a specification to exemplify every composition that falls within the scope of the claims it must be reasonable to extrapolate from the specific compositions exemplified to those that are claimed. Thus the first question to ask is, is it reasonable to expect that the behaviour observed for small heterocyclic drugs represents a principle that is applicable to all drugs.
63. ARC submit that this is the case, that their invention is a "platform invention", where prolonged delivery is a product of the behaviour of drugs in general when they are present in FG at concentrations greater than their solubility in the FG.
64. The specification provides two examples of solid drugs loaded in excess of their solubility in FG. The first example, example 16 and related figure 30 describe prolonged delivery of a drug, 5-FU when the drug is loaded in FG in solid form in an amount exceeding the solubility of the drug in the FG.
65. The second example, example 12 discloses the antibiotics, tetracycline, ciproflaxin, amoxicillin and metronidazole, loaded in FG in differing amounts. In particular figure 24, 26 and 27 demonstrate prolonged delivery when tetracycline and ciproflaxin are loaded in excess of their solubility in FG.
66. Thus there are two examples disclosing consistent release behaviour for a number of drugs loaded in excess of their solubility in FG. Both examples clearly demonstrates quite different and delayed release kinetics when a drug is present in an amount in excess of its solubility, in contrast to the same drug present in either soluble form, or in solid form in an amount below its solubility. Thus it seems reasonable to accept that the applicant has discovered a principle that is related to the amount of a compound that is loaded in FG, rather than the chemical nature of the compound itself and that this principle can be extrapolated to all drugs loaded in FG.
67. Further support for release kinetics governed by the amount of drug present with respect to the solubility of the drug, and independent of drug type or chemistry can also be found in the Friedman declaration.
68. Dr Friedman teaches that same release kinetics are seen for a range of drugs loaded in FG in amounts in excess of their solubility in the FGs. The Friedman declaration at 10.0-10.2 and slides 7-11 of SAF-4 demonstrates prolonged delivery for lidocaine, ciprofloxacin and ampicillin when these drugs are loaded in FG in amounts exceeding their respective solubilities.
69. All of this suggests that it is reasonable to predict that there is a broad principle that applies to all drugs when loaded in FG in amounts in excess of their solubility in FG and that this principle provides support for the claims.
70. Given this the onus is on Baxter to provide me with evidence to the contrary. However they have not provided me with any such evidence and thus, I have nothing to suggest that the applicant has not discovered a general principle that provides fair basis for claims 1-19.
71. Baxter also submitted that the claims relating to methods for preparing FGs lacked fair basis. They stated that although the specification provided examples of methods for preparing FG supplemented with 5-FU in excess of its solubility, it disclosed that this method did not work when fibrin was supplemented with TET.
72. The problem with TET is disclosed at page 12 of the specification, where it is stated that fibrin preparations will not polymerise when they are supplemented with the freely water soluble form of TET, TET-HCl. However, this problem is resolved in example 12 where TET-supplemented FG is prepared using the poorly soluble free base form of TET.
73. Although I accept that the specification does disclose a problem with preparing FG supplemented with one form of TET, TET-HCl, I do not believe that this should be construed as a demonstration that the invention does not work for a specific drug. I believe that, in the context of the specification, the term drug should be construed as relating to the active constituent of the drug rather than specific formulations of a particular drug. Therefore the problem with TET-HCl simply demonstrates a problem with one form of TET and example 12 provides a solution to this problem through the use of a different TET formulation.
74. As such I see nothing to suggest that it is unreasonable to extrapolate from the methods disclosed in the specification to the preparation of all drug-supplemented FGs. Thus I am satisfied that there is fair basis for the methods of claims 20-26.
75. In summary, I am satisfied that that the specification does meet the requirements for fair basis of the supplemented tissue sealants and processes of preparation of such sealants that are the subjects of claims 1-26.
76. Baxter also objected to the one remaining claim, claim 27, on the grounds that it lacked fair basis and clarity. However I have dealt with it as a separate issue in a later section.
77. Baxter also argued that the invention was not fully described with respect to both the compositions of claims 1-19 and the methods of claims 20-26. These arguments also revolve around the issue of extrapolation from the behaviour of 5-FU and antibiotics to the behaviour of drugs in general. As such I believe that these issues have been fully addressed in the preceding passages.
(3) Claims 20-26 are not fairly based because they do not define a specific protein concentration.
78. Baxter also submitted that the claims lacked fair basis with respect to the protein concentration in the fibrinogen component of the FG. They argued that the specification disclosed that a specific protein concentration of 60 mg/ml was essential and that the claims did not reflect this range.
79. However Mr Roberts explained that it was well understood in the art that a broad range of protein concentrations could be used and that it was only essential to use a protein concentration of 60 mg/ml when preparing FGs for the limited range of applications where it is also essential that the FG preparation does not inhibit full thickness wound healing. This is supported in the specification. Pages 8 and 33-36 disclose the broad range of protein concentrations that can be used when preparing FG and example 10 discloses that 60 mg/ml is particularly effective when it is important that the sealant does not inhibit full thickness wound healing.
80. Support for this can also be found in the Kanellos declaration at paragraph 20, where Kanellos explains that a protein concentration of 60 mg/ml is only required when preparing FG compositions that "do not inhibit full thickness skin wound healing"
81. As such I am satisfied that there is no requirement for the claims to be limited to 60 mg/ml unless the claims disclose a specific embodiment of the invention where it is essential that the FG does not inhibit full thickness wound healing. Although there is one claim that does specifically define a supplemented FG that does not inhibit full thickness skin wound healing, this claim also specifies a protein concentration of 60 mg/ml.
(4) Claim 27 is not clear.
82. Baxter also submitted that claim 27 lacks clarity. The claim recites a method for preparing a FG supplemented with a drug in solid form wherein the supplemented FG is prepared by immersing the FG in a solution of the drug. It is not clear whether the claim recites an adaptation of examples 12 and 16 where both solid drug and drug in solution are used to prepare the supplemented FG, or whether the claim defines further undisclosed methods. If the latter construction is intended and the claimed methods diverge from the methods of examples 12 and 16, there is no support for these methods in the specification. There is also no further guidance with respect to the interpretation of this claim in the specification.
83. ARC conceded that there were clarity problems with the claim and that these could be rectified with amendment. I agree that the claim is not clear.
Manner of manufacture
Baxter also submitted that the claimed invention was not a manner of manufacture. However they chose not to pursue this matter at the hearing and conceded that it was an issue closely aligned to the question of inventive step. As such I believe that it has been fully considered above.
Conclusion
The opposition is successful with respect to the lack of clarity for claim 27 and I allow ARC 60 days from the date of this decision to propose suitable amendments to the claim.
However, the opposition fails on the grounds of full description, novelty, inventive step and manner of manufacture with respect to the remaining claims, claims 1-26.
Costs
87. Costs will normally follow the event, however I consider that, as requested by Dr Finney, costs should be awarded against the applicant up to 14 February 2001; the date at which the amendments were incorporated into the specification.
88. Prior to the amendments claim 1 simply recited:
A composition of matter, comprising a tissue sealant and a drug, wherein said drug is present in said tissue sealant in solid form"
89. There was no limitation with respect to the amount of drug loaded, or suggestion that the drug was present in an amount in excess of the solubility of the drug in the sealant. As such, there was no clear limitation to compositions that would inherently provide the advantageous drug release profile that the applicant has named as a key feature of the invention.
90. The amendments introduced this key feature into the claims, providing some much-needed focus to the specification and clearly distinguishing the applicant's invention from the prior art.
91. However, although they substantially improve the quality and clarity of the specification, their tardy insertion has put the opponent to substantial unnecessary effort in preparing a case that is now substantially irrelevant as a consequence of the amendments. As such I believe that it is appropriate that costs should be awarded to the opponent up to the date at which the amendments were incorporated into the specification.
Costs after this date are awarded against the opponent as a consequence of the failure of the majority of the opposition.
GILLIAN JENKINS
Delegate of the Commissioner of Patents
Patent attorneys for the applicant : Davies Collison Cave, Melbourne
Patent attorneys for the opponent : Cullen & Co., Brisbane
0
0
0