Introduction
On 3rd September 2025, Federal Court Judge Rofe handed down her decision[1] in relation to an application for an interlocutory injunction based on Regeneron’s Australian Patent No. 2012205599 entitled “Use of a VEGF Antagonist to Treat Angiogenic Eye Disorders” (the 599 Patent). The 599 patent basically claims a dosage regimen utilising the pharmaceutical Aflibercept to treat various angiogenic eye disorders with injections being provided 2 to 4 weeks after the initial dose and then at 8-week intervals thereafter.
The interlocutory injunction application was refused on the basis of a preliminary finding that the Product Information (PI) sheet associated with the allegedly infringing Sandoz Aflibercept product, AFQLIR®, did not amount to instructions to duplicate the claimed dosage regimen, so no prima facie case of patent infringement existed.
In addition, her Honour rejected an argument of lack of novelty based on reports of clinical trials conducted by the patentee, Regeneron, prior to the priority date of the 599 patent.
Regeneron appealed the decision. The appeal was heard by the Full Federal Court on 29th October 2025 and a decision on the appeal is to be handed down tomorrow (19th November 2025).
The Non-Infringement Finding – an Equitable Result?
The main claim (claim1) of the 599 patent reads as follows
A method for treating an angiogenic eye disorder in a patient, comprising: sequentially administering to the patient a single initial dose of a VEGF antagonist, followed by one or more secondary doses of the VEGF antagonist, followed by one or more tertiary doses of the VEGF antagonist;
wherein each secondary dose is administered 2 to 4 weeks after the immediately preceding dose; and
wherein each tertiary dose in administered 8 weeks after the immediately preceding dose
wherein the VEGF antagonist is a VEGF receptor-based chimeric module comprising:
(1) a VEGFR1 component comprising amino acids 27 to 129 of SEQ ID NO:2;
(2) a VEGFR2 component comprising amino acids 130-231 of SEQ ID NO:2; and
(3) a multimerization component comprising amino acids 232-457 of SEQ ID NO:2.
The specific VEGF agonist used is the pharmaceutical Aflibercept.
It is relevant to note that the primary, secondary and tertiary doses may be, and in use are, exactly the same. Thus, the only variant is the period between administration of the various doses.
The question of infringement thus turned on the question of whether the PI Sheet relating to AFQLIR® constituted instructions to follow this dosage regimen.
As Rofe J. put it, the infringement question reduced to:
“(a) a construction argument on whether an “instruction” to inject the relevant drug once a month amounts to an instruction to use it 4 weeks after the preceding dose;
(b) a construction argument on whether an “instruction” to administer the product two months after the preceding dose amounts to an instruction to use it 8 weeks after the preceding dose; and
(c) an argument on whether the “clear instructions” in the Sandoz PI in relation to Wet AMD that the product be administered “every two months” is overtaken by the introductory statement that when optimal visual acuity is achieved and/or there are no signs of disease activity, a treat-and-extend regimen may be used.”
Her Honour, perhaps surprisingly, concluded that:
“At this stage, my provisional view is that “one month” or “each month” is not equivalent to “2 to 4 weeks”, and the language used by the Sandoz PI regarding the dosing regimen does not cause it to fall within claim 1 (emphasis added)”.
Her Honour similarly concluded that 8 weeks is not equivalent to 2 months.
The conclusions by Rofe J. were criticised by Counsel for Regeneron on appeal, as being overly literal and for not taking into account other sections of the AFQLIR® PI sheet that suggested a less literal use of the language relating to one and two months, by Sandoz itself.
Whether those arguments are, or are not, successful remains to be seen. However, I would suggest that such critiques fail to recognise an underlying equity principle of patent law in play here. That is, the scope of monopoly awarded to the patentee should be commensurate with the quantum of advance in the art represented by the invention disclosed.
This is reflected in U.S. jurisprudence with the requirement that the data submitted in a patent application must be “commensurate in scope with the claims” sought to be granted[2].
My proposition is that Rofe J. had in mind such equitable concepts when she applied a very strict construction to the language of the claims. That is, the contribution to the art reflected in the very simple dosage regimen claimed, justified only a very limited scope of protection; that limited scope of protection requiring a narrow construction of the language of the claims. As Professor Smith argued in “Putting the equity back into Intellectual Property Remedies” [3]
“Equity steps in to modify the result the law provides. Equity refers to the law, acts on the legal result, and sometimes moulds the law, but not vice versa: the law can operate (sometimes badly) without equity’s intervention”.
In analysing the nature and scope of the invention claimed, her Honour has recognised that an ‘invention’ of such limited scope does not warrant an expansive construction. On the contrary, she has recognised that the alleged invention is marginal at best and that such a marginal invention supports only a marginal scope of claim.
If I am correct in my supposition, her Honour should be congratulated for her courage in bearing in mind in her decision the equitable underpinnings of Patent Law.
The Novelty Finding – an Inequitable Result?
A significant amount of time was spent during the Hearing at first instance and on appeal on the question as to whether the claims were in fact so clearly invalid for lack of novelty as to preclude the granting of an interlocutory injunction.
The prior art included two articles, Adis[4] and Dixon[5], both of which described the clinical trials being conducted with Aflibercept by Regeneron for the treatment of eye disorders. Those articles identified Aflibercept by name as the active ingredient and described the use of a dosage regimen consistent with the claims of the 599 patent.
However, neither article specifically described the amino acid sequence contained in Aflibercept (SEQ ID No 2), as required by claim 1 of the 599 patent.
Sandoz argued that the amino acid sequence is inherent in the name “aflibercept”. Sandoz further argued that details of the amino acid sequence could be sourced from, for example, the U.S. Pharmacopeia Dictionary[6], if that was deemed necessary.
Sandoz further argued that carrying out the directions in the prior art “will inevitably result in something being made or done which […] would constitute an infringement of the patentee’s claim […]”. This is the so-called “Inevitability argument” as recited in Novozymes.[7]
Rofe J. relied on the language of the Full Federal Court in the Sandoz AG v Bayer Intellectual Property GmbH[8] decision to reject the ‘inevitability’ argument. She found:
“Without the essential integer of the amino acid sequence of aflibercept, the skilled person is unable to work the directions in Adis or Dixon, without impermissible resort to other sources of information. Sandoz’s attempt to plug the information gap in Adis and Dixon with its inherency and inevitability argument must fail at this preliminary stage.”
The term “information” is taken from Section 7(1) of the Patents Act 1990 where it is stated “… that an invention is taken to be novel when compared to the prior art base unless it is not novel in light of certain kinds of information, each of which must be considered separately unless the person skilled in the art would treat them as a single source of information.”[9].
This point was reiterated by Counsel on behalf of Regeneron on appeal. In contrast, Sandoz’s Counsel was at pains to point out that the test for lack of novelty is a hypothetical one. He argued that Sandoz was not relying on other sources of information, but rather that once the skilled addressee had in her/his possession the knowledge that the drug to be used was Aflibercept, nothing further was needed. If Aflibercept is used as the VEGF agonist, the agonist inherently has the amino acid sequence claimed.
Whilst recognising the intellectual strength of their Honours sitting as the Full Federal Court, I would suggest that the question of equity in Intellectual Property cases has, in this instance, been overlooked. The use of the word “work” in the extract above is instructive. I would suggest that the information regarding the amino acid sequence does no “work”. Once the skilled addressee is told to use Aflibercept, all the ”work” to duplicate the invention claimed has been done.
The Adis and Dixon articles, on this view, have each provided the public with all the ‘information’ required by the claims of the 599 patent. The only integer not explicitly provided is the detail of the amino acid sequence present in Aflibercept. However, if one is given the information that Aflibercept is to be used, the amino acid sequence inevitably follows.
From an equity perspective, are the public provided with any more information by the 599 patent than they already had via Adis or Dixon? In my view, the answer is no.
Thus, in equity, the finding that the claims of the 599 patent are novel and thus valid, represents an inequitable result. The public is burdened with the grant of a patent monopoly, but received nothing new in exchange for that burden. To put it another way, to require the amino acid sequence to be disclosed is to confuse requiring one to have the ‘tool kit’ to be able to ‘work’[10] the invention, with having the information required to do so.
Conclusion
The Regeneron decision is a fascinating one as it raises fundamental questions of Australian Patent Law which, at first blush, may be thought to have long since been fully established; namely what constitutes an infringement and when can a claimed invention be said to be not novel. My proposition is that such issues are always fluid and depend on the specific facts of any case.
Further, when considering such fundamental questions, it is enlightening to remember the equitable principles that underpin all intellectual property rights including, in particular, patent rights. If an analysis of the law leads to a conclusion that is arguably inequitable, it may be prudent to revisit that analysis.
[1] Regeneron Pharmaceuticals Inc v Sandoz Pty limited [2025] FCA 1067
[2] In re Tiffin, 171 U.S.P.Q. 294 (C.C.P.A. 1971
[3] 96 Notre Dame L. Rev. 1603 (2021)
[4] Adis Data Information BV, “Aflibercept,” (2008): 9(4) Drugs R&D, page 261-269, published in 2008.
[5] Dixon, J.A., et al, “VEGF Trap-Eye for the Treatment of Neovascular Age-related Macular Degeneration”, (2009): 18(1) Expert Opin. Investig. Drugs, 1573–1580, published in 2009 .
[6] US Pharmacopeia Dictionary of United States Adopted Name and International Drug Names and the World Health Organisation International Nonproprietary Names List.
[7] Novozymes A/S v Danisco A/S (2013) 99 IPR 417 at [145] (Jessup J), citing General Tireand Rubber Co v Firestone Tyre and Rubber Co Ltd (1971) 1A IPR 121 at 138 (Sachs LJ); see also Mylan Health Pty Ltd v Sun Pharma ANZ Pty Ltd (2020) 279 FCR 354 at [84] (Middleton, Jagot, Yates, Beach and Moshinsky JJ).
[8] Sandoz AGv Bayer Intellectual Property GmbH (2024) 183 IPR 309 at [117] (Yates, Burley and Downes JJ)
[9] Ditto at [195].
[10] Regeneron Pharmaceuticals Inc v Sandoz Pty limited [2025] FCA 1067 at [197].
