The Circumstances in which Juno Came to Make the Ester Admission and the Circumstances Leading to its Application to Withdraw it
11 A convenient starting point is the affidavit of Mr Jones. He sets out the matters to which he deposes in chronological order.
12 The following facts are based on information provided to Mr Jones by Mr Andrew Brown who is the Head of Intellectual Property at Juno. By way of introduction, he states that Juno seeks leave to withdraw the Ester Admission. Juno admits that its products are made using are N-(2-pyrazine) carbonyl-L-phenylalanine-L-leucine boronic acid (bortezomib) and D-mannitol, and it also admits that its products are in the form of a lyophilised compound. For reasons set out below, Juno now understands that when an aqueous solution of N-(2-pyrazine) carbonyl-L-phenylalanine-L-leucine boronic acid and D-mannitol is formed and lyophilised, those compounds are unlikely to give the D-mannitol boronate ester of bortezomib.
13 Mr Jones states that Juno provided the instructions to make the Ester Admission because at the time it was made, the following circumstances applied.
14 First, Juno had no reason to consider that the representations in the Formulation Patent were incorrect, namely that when an aqueous solution of the relevant boronic acid and D-mannitol is formed and lyophilised, those two components react to form the boronate ester as indicated in particular paragraphs of the Formulation Patent. Paragraph 141 of the Formulation Patent sets out the results of an experiment which apparently indicated the existence of the boronate ester - in particular, a signal was seen upon Fast Atom Bombardment mass spectral analysis of the lyophilised product that equated to the molecular weight of the boronate ester. Furthermore, when the lyophilisate is reconstituted in an aqueous medium, an equilibrium is established between the boronate ester and the corresponding boronic acid as stated in paragraph 137 of the Formulation Patent.
15 Secondly, Juno had no reason to consider that the following representations made in the affidavit of Mr Dewar affirmed on 15 August 2018 and referred to in the particulars to paragraph 17 of the Amended Statement of Cross-claim were incorrect, namely that the cross-claimant's VELCADE product, when "a freeze-dried (lyophilised) powder … consists of mannitol boronic ester"; and that the VELCADE product as "a reconstituted solution (in saline) … consists of both mannitol boronic ester and Bortezomib (monomeric boronic acid) in equilibrium".
16 Thirdly, Juno had no reason to consider that the assumption Dr Althea S.-K. Tsang, patent attorney, was asked to make as referred to in her affidavit affirmed on 15 August 2018 was incorrect, namely that the Juno generic products are supplied in the form of a powder comprising the mannitol boronic ester of bortezomib.
17 Fourthly, Juno's relationship with the manufacturer of its generic products (i.e., Juno's supplier) was and is at arms-length, and information held by the manufacturer regarding the manufacture and composition of the Juno generic products was not known to Juno except as set out in the product information (PI) leaflets referred to in the particulars to paragraph 17 of the Amended Statement of Cross-claim, the documents provided to the Therapeutic Goods Administration (the TGA Material) and the further Common Technical Documents (CTD) received from the supplier. The PI leaflets stated that the product was provided as a mannitol boronic ester which, in reconstituted form, consists of the mannitol ester in equilibrium with its hydrolysis product, the monomeric boronic acid, and information in the CTD which described the nature of the bortezomib API (active pharmaceutical ingredient) present in Juno's generic products.
18 In addition to these matters, Juno had previously obtained evidence from an expert witness, Dr Angelo Morella, who was retained by Jones Tulloch on behalf of Juno to give evidence in support of two re-examination requests in respect of the Formulation Patent that Juno filed with the Patent Office in November 2017 and April 2018 respectively. Dr Morella's evidence was to the effect that a boronate ester could result when the solution described above is formed. Dr Morella did not raise any issue about the correctness of the assertion in the Formulation Patent that a boronate ester would result in the circumstances.
19 Mr Jones states that Mr Brown had a telephone conversation with Juno's supplier's head European patent attorney, Mr Frank Benneker, in late September 2018 in relation to European Patent EP [REDACTED] and during the conversation Mr Benneker informed him that there was a dispute with Millennium as to whether the mannitol ester was present in the bortezomib product supplied by Juno's supplier in parts of Europe or not, but information about the basis for any uncertainty was not provided. This was the first time that Mr Brown of Juno became aware of any such uncertainty.
20 Mr Jones states that Mr Brown was aware of the matters which led Juno to make the admissions and did not understand, based on his discussion with Mr Benneker, that there was at that time a basis for seeking to withdraw the admissions that had been made in the proceeding. However, he was aware that Juno would be retaining an expert witness to give evidence as to matters of chemistry in this proceeding.
21 Jones Tulloch first received details of the manufacturing process for Juno's generic products on 10 October 2018, which were provided by Juno's supplier. These documents were titled "Control of Materials" and "Description of Manufacturing Process and Process Controls" and they provided a detailed description of the manufacturing process and materials used to synthesise the API used in Juno's generic products.
22 Biopharmalex, on behalf of Juno, retained Dr Robertson to give expert evidence in this proceeding. An affidavit by Dr Robertson was filed on 18 January 2019. On 4 December 2018, Juno first became aware of the following:
16. … it was Dr Robertson's view that a solution of N-(2-pyrazine) carbonyl-L-phenylalanine-L-leucine boronic acid and Dmannitol may not react to form the boronate ester and nor may it form upon lyophilisation. In particular, Dr Robertson expressed the following views:
(a) Without the use of a catalyst or some other driving force, it is unlikely that mannitol would form any ester with the boronic acid described as "2-Pyz-(CO)Phe-Leu-B(OH)2" in the paper by Wu et. al. titled "Degradation Pathways of a Peptide Boronic Acid Derivative, 2-Pyz-(CO)-Phe-Leu-B(OH)2" and also identified as compound MG-341 in US 5,780,454 (the Compound).
(b) Such an ester would not be formed because mannitol, in a neutral solution, is generally non-reactive and stable. In order for mannitol to react with the API, it would first need to be deprotonated, and that can only occur in the presence of a strong base and, moreover, the Compound is not sufficiently basic to deprotonate mannitol. Furthermore, even if such a reaction between mannitol and the API were to occur, it would be an equilibrium process in an aqueous solution. Such an equilibrium would lie heavily towards the dissociated state (away from any ester being formed) because the excess concentration of water would disrupt any such ester bond. Finally, the process of freeze drying itself would not be a sufficient driving force to create such an ester.
(c) Notwithstanding the description of the theoretical ester structures in paragraphs [0065] to [0070] of the Formulation Patent, there is no conclusive evidence in the Patent that shows that the inventors in fact made compounds having such structures, and he cannot see the use of any catalyst or other driving force which would bring about any mannitol ester being formed of the Compound.
(d) The only experimental evidence that seeks to establish that such an ester was created is in paragraph [0141] of the Formulation Patent. However, the mass spectrometry results that are described at paragraph [0141] are far from conclusive and there are other reasons for the signal observed at m/z 531, including a signal caused by mannitol attached to another part of the Compound other than the boronic acid, or a signal caused by two glycerol molecules attached to the Compound (noting that glycerol is used in the experiment).
(e) The Patent itself describes the lyophilisate in paragraph [0143] as "a "lyophilised formulation of N-(2-pyrazine)carbonyl-L-phenylalanine-L-leucine boronic acid with D-mannitol:, not a mannitol ester of the boronic acid and the reconstituted solution in Example 3 that was analysed by HPLC apparently only showed the Compound, not a mannitol ester of the Compound.
23 On 5 December 2018, Biopharmalex sent a letter to the solicitors for Millennium seeking their consent to the withdrawal of (effectively) the Ester Admission. On 7 December 2018, the solicitors responded seeking the provision of further details in respect of Biopharmalex's letter dated 5 December 2018. On 20 December 2018, Biopharmalex responded providing the requested details which are set out in the quote from Mr Jones' evidence. On 21 December 2018, the solicitors for Millennium informed Juno that Millennium did not consent to the withdrawal of the Ester Admission.
24 On 18 February 2019, the solicitors for Millennium wrote to Biopharmalex foreshadowing proposed further amendments to its pleadings in the proceeding, including the introduction of a new allegation of infringement of Australian Patent No 2016202747. Biopharmalex responded to that letter on 27 February 2019 and confirmed a conditional consent to the filing by Millennium of further amended pleadings, one of those conditions being that Millennium gave its consent to the withdrawal of the Ester Admission by Juno. On 1 March 2019, the solicitors for the respondents sent a letter to Biopharmalex which stated that should their client bring any application to seek to withdraw any of its admissions, their client would oppose that application. Juno issued this interlocutory application on 5 March 2019.
25 Mr Condon deposed to the fact that he sent the fifth Dewar affidavit and annexures to that affidavit to Dr Robertson and he asked Dr Robertson to consider whether the material changed the views he had expressed in his affidavit regarding the formation of a mannitol ester of bortezomib and, if not, why, and if the experimental data material was unclear, how it could be improved. Dr Robertson's advice to Mr Condon is expressed by Mr Condon in the following way:
6. Having considered the Material, he remains of the view that it is unlikely that mannitol and bortezomib would form an ester without some driving force. The driving force could be either a catalyst of some nature (usually a base) or by being brought together in non-aqueous solvents under dehydrating conditions such as refluxing toluene with a water trap or in anhydrous solvents in the presence of molecular sieves.
26 Dr Robertson referred to the scientific tests which have been provided to him. He referred to the 1H NMR data. He said that the interpretation of such data would be greatly assisted by a clear identification of the boronic acid protons and an integration of all peaks in the spectrum. In particular, a deuterium exchange experiment would help him identify the acidic protons in the molecule.
27 I should say at this point that I infer that the deuterium experiment is the experiment which counsel for Juno referred to in the course of his submissions. Counsel said that the experiment "takes all of minutes to do, certainly no longer than a day". I asked counsel for Juno why Dr Robertson had not done the experiment if it was such a simple experiment. He responded as follows:
Your Honour, we haven't had him do it, because, on the basis of what he has said, your Honour, and the information that is obtained by way of experiment, there's no need to. He says that the mannitol ester just does not form.
28 Counsel's reference to the experiment occurred in the context of a submission by him to the effect that Juno concedes that if Millennium can establish that its product has the mannitol ester, then Juno accepts that its products also have the mannitol ester.
29 I mention at this point that Millennium submits that it is a significant consideration against the granting of Juno's application that it has not done an experiment which it describes as a simple experiment.
30 I turn now to Mr Dewar's fifth affidavit. Millennium has engaged two experts. The first expert is Dr Roger Snow who is an Adjunct Professor of Organic Chemistry at Vassar College and a Medicinal Chemistry Consultant. He has expertise in boronic acid chemistry. The second expert is Dr Bradley Anderson who is a Professor of Pharmaceutical Sciences at the College of Pharmacy, University of Kentucky. Mr Dewar refers to the admissions made by Juno. He identifies the admissions as, in effect, amounting to an admission that Juno's proposed product contains the D-mannitol boronic ester of bortezomib.
31 Mr Dewar states that Juno has made representations to the Australian Therapeutic Goods Administration (TGA) consistent with the Ester Admission as part of its application to obtain approval to register Juno's generic products on the ARTG. Furthermore, Juno has made representations to the Patent Office consistent with the Ester Admission in its applications for re-examination of the Formulation Patent and in consultation with Juno's independent expert, Dr Morella. The second request for re-examination of the Formulation Patent was made by Juno on 10 April 2018 and relied on two declarations by Dr Morella. I do not need to set out the details of the representations to the TGA other than to state that they appeared in Juno's PI and in the CTD Modules submitted to the TGA. Nor is it necessary for me to set out the representations made to the Patent Office.
32 Mr Dewar sets out the history of this proceeding and submits that the effect of the correspondence between the parties is that if this application is refused, Juno will have admitted infringement of the Method Claims in the Formulation Patent because it will not have withdrawn its admission of the Ester Admission, and the remaining integers have each been admitted. Mr Dewar contends that if Juno's application is allowed, then it will be necessary for Millennium to file additional evidence-in-chief on the question of infringement to address the changed denial. Mr Dewar also states that if Juno is allowed to withdraw its admissions, then Millennium will apply to join Juno's supplier as a cross-respondent to the proceeding. Millennium will allege (at least) that Juno's supplier threatens to authorise Juno's infringement of the Compound Patent and Formulation Patent and to be part of a common design with Juno to infringe those patents.
33 Mr Dewar deposes to the fact that Juno's supplier is located in the Netherlands and unless it accepts service of the Amended Originating Application, Millennium will have to apply for leave to serve outside Australia. He considers that it may take many months to serve Juno's supplier under the Hague Convention on the Service Abroad of Judicial and Extrajudicial Documents in Civil or Commercial Matters 1965. Mr Dewar states that once Juno's supplier has been served, it will need to be given an opportunity to file a Defence to Millennium's Amended Cross-claim and, in doing so, it will need to plead to the Ester allegation. Millennium will seek verified discovery from Juno's supplier of manufacturing documents disclosing the manufacturing processes for Juno's generic products and analyses of Juno's generic products. Mr Dewar states that Millennium will need this discovery in light of Juno's denial that Juno's generic products contained the D-mannitol boronic ester of bortezomib. Mr Dewar states that Millennium will need this discovery even if Juno's supplier admits that Juno's generic products contain the D-mannitol boronic ester of bortezomib because of Juno's denial. Mr Dewar states that Millennium will need discovery from Juno's supplier before it can file affidavit evidence-in-chief on infringement in respect of establishing that Juno's generic products contain the D-mannitol boronic ester of bortezomib. Furthermore, Mr Dewar states that instructions would need to be given to Millennium's experts and that, based on the Court's practice, a joint conference of experts is likely. Mr Dewar expresses the opinion that if Juno is permitted to withdraw the Ester Admission then, based on the above timetable, he does not consider that it would be possible to maintain the trial dates in July of this year. This will be inconvenient to Millennium's experts, namely Dr Snow and Dr Anderson, "who have made arrangements to ensure that they are available to travel to Australia to give evidence in the July hearing and so that they are available in June/early July for the purpose of any joint expert conferral process".
34 Mr Dewar addresses the proceedings in Europe. These proceedings were in relation to European patent EP [REDACTED], which is the European equivalent of the Formulation Patent. The proceedings were opposition proceedings before the European Patent Office and the decision of the European Patent Office was delivered on 7 March 2019. The parties to the opposition included, relevantly, Juno's supplier and Lek. There was no consideration of Juno supplier's product during the European opposition.
35 Mr Dewar states that in the European opposition, Juno's supplier challenged the sufficiency of the disclosure of EP [REDACTED] based on, relevantly, the argument put by Juno's supplier that: the Mass Spectrometry did not demonstrate that combining mannitol and bortezomib in an aqueous solution, which solution is then lyophilised, forms the monomeric mannitol boronic ester of bortezomib; that the Mass Spectrometry data from the expert report prepared by Lek did not demonstrate that combining mannitol and bortezomib in an aqueous solution, which solution is then lyophilised, forms the monomeric mannitol boronic ester of bortezomib; and the correct position is that combining mannitol and bortezomib in an aqueous solution, which solution is then lyophilised, forms a dimeric mannitol boronic ester of bortezomib. Mr Dewar contends that:
[Juno's supplier's] argument in relation to the dimeric mannitol boronic ester being formed is inconsistent with the evidence of Dr Robertson who believes that combining mannitol and bortezomib in an aqueous solution, which solution is then lyophilised, is "unlikely" to form any mannitol boronic ester of bortezomib (in the absence of a catalyst) …
36 Juno's supplier's arguments were rejected by the European Patent Office which found that the monomeric mannitol boronic ester was formed. The European Patent Office stated that the Fast Atom Bombardment Spectrometry and the Nuclear Magnetic Resonance Spectrometry provided conclusive evidence that combining mannitol and bortezomib in an aqueous solution, which solution is then lyophilised, results in the formation of the monomeric mannitol boronic ester of bortezomib. Finally, Mr Dewar states that he is informed by Dr Snow and Dr Anderson that each of them disagrees with Dr Robertson's view that it is unlikely that a boronic ester will be formed. Dr Snow and Dr Anderson have expressed the view to Mr Dewar that a solution of bortezomib and D-mannitol will react to form a monomeric mannitol boronic ester of bortezomib and that upon lyophilisation of that solution, the lyophilised product will contain the monomeric mannitol boronic ester of bortezomib.
37 The main matter addressed by Mr Dewar in his sixth affidavit is as follows. Millennium has asked Juno to identify precisely what form it now seeks to allege that its drug product is in and has received a response from Juno to the effect that "there is some uncertainty as to what precise chemical form Juno's Generic Products are in" and Juno's position is that "Juno's Generic Products are not in the form of a lyophilised mannitol ester of bortezomib".