Australian courts have developed a distinctive body of case law regarding the use of clinical trial documents — including protocols, participant information sheets, and consent forms — as prior art capable of destroying novelty of a patent claim. The Australian Patent Office (APO) decision in Grünenthal GmbH [2026] APO 9 (“Grünenthal”; discussed below) is a recent example of how the APO applies this case law during examination of Swiss-style and therapeutic method claims. This article will provide a brief review of the case law from higher courts before discussion of Grünenthal.
Federal Court of Australia Case Law Summary
In Bristol-Myers Squibb Co v F H Faulding & Co Ltd [2000] FCA 316, the Federal Court held that Phase I trial disclosures relating only to compound safety did not anticipate method of treatment claims as there was no disclosure of efficacy or did not relate to or show efficacy data. This decision set an early baseline that safety-related disclosures in Phase I protocols would not suffice to destroy novelty of efficacy-based claims.
In InterPharma Pty Ltd v Hospira Inc (No 5) [2019] FCA 960, the Court confirmed that patient consent forms qualify as prior art. However, the forms did not disclose each and every essential feature of the claimed invention with sufficient specificity, and therefore was not factually an anticipatory disclosure. The patent was not held to be anticipated by the patient consent form. It is noteworthy that the patient consent form may have been considered novelty-destroying if the forms disclosed a greater level of technical detail.
The precedential authority is Mylan Health Pty Ltd v Sun Pharma ANZ Pty Ltd [2020] FCAFC 116 (“Mylan”), where a five-judge Full Federal Court held that method of treatment and Swiss-style claims lacked novelty in light of the publicly disclosed ACCORD Eye Study Protocol, which contained only an unproven hypothesis about fenofibrate’s effect on diabetic retinopathy – the protocol hypothesised that administering fibrate to a particular patient subset would reduce the risk of diabetic retinopathy. The Full Court confirmed that the central question is simply what the prior document discloses, and that scientific validation of a hypothesis is not required for a finding of anticipation. An important caveat is that the disclosure must be sufficiently specific and complete to identify the claimed invention to be an anticipatory disclosure. The High Court of Australia refused special leave to appeal and thus the decision in Mylan is binding law in this regard.
Background to Grünenthal
AU2008241013 granted to Grünenthal GmbH relates to a titration method for administering tapentadol — a centrally acting analgesic used for moderate to severe acute or chronic pain. The specification identified somnolence as one of tapentadol’s most frequently reported adverse events and one of particular concern, noting it may impair daily living and lead to early discontinuation of treatment. The stated object of the invention was to improve tolerability of tapentadol — particularly to reduce the frequency of somnolence — without diminishing efficacy or patient compliance.
The inventive concept was a three-step dose titration regimen: starting at a low dose (50 mg or 100 mg twice daily), increasing to a second dose after 1–3 days, and increasing again to a third dose after a further 3–11 days, with each dose increase of 50 mg. Claim 1 was a Swiss-style claim directed to the use of tapentadol in the manufacture of a medicament for the treatment of pain with a lower incidence of somnolence, administered according to this stepped regimen. Independent Claim 33 is a corresponding method of treatment claim.
On 9 February 2024, AU Pharma Pty Ltd filed a re-examination request. Five adverse re-examination reports followed before the Commissioner indicated intention to revoke the patent, prompting Grünenthal to request a hearing.
The Prior Art Document — D2
The sole prior art document under consideration was a publicly available clinical trial record published on ClinicalTrials.gov on 1 April 2007 — before the patent’s priority date of 23 April 2007. The study was titled “A Study to Evaluate Long-Term Safety of Multiple Doses of Tapentadol (CG5503) Prolonged-Release (PR) and Oxycodone Controlled-Release (CR) in Patients With Chronic Pain” (NCT00361504), sponsored by Johnson & Johnson Pharmaceutical Research & Development.
The Delegate described D2 as a Phase III, one-year, randomised, open-label, parallel-arm safety trial of prolonged release tapentadol against controlled-release oxycodone, with controlled dose adjustment, in patients with chronic pain. The treatment arm set out the following dosage instructions: patients would start on CG5503 PR 50 mg twice daily; after 3 days the dose would increase to 100 mg twice daily for the next 4 days; thereafter, upward titration could occur at minimum 3-day intervals in increments of 50 mg up to a maximum of 250 mg twice daily. The primary outcomes measured incidence of adverse events in general, along with laboratory measures, physical examinations, and echocardiograms over one year. Secondary outcomes included constipation, vomiting, sleep, pain intensity, and patient global impression of change.
Grünenthal’s Arguments on Novelty
Grünenthal advanced three grounds on which it contended D2 failed as a novelty citation.
First, D2 did not disclose how the prolonged release form of tapentadol was achieved.
Second, D2 did not identify somnolence as a side effect to be minimised by titration — somnolence is not mentioned in D2 at all, and the patentee’s expert Dr Milton Cohen confirmed he would not have known at the priority date that somnolence associated with tapentadol could be minimised by titration. Grünenthal also noted D2 referred to sleep assessments, whereas somnolence — occurring while a patient is awake — is a distinct phenomenon.
Third, Grünenthal contended that the third titration step in D2 was framed as optional, and therefore the three-step regimen of claim 1 was not taught.
The Delegate’s Reasoning — Inevitable Result
The Delegate rejected each of Grünenthal’s arguments and found that independent claims claims 1 and 33 lacked novelty in light of D2.
On the dosing regimen, the Delegate set out D2’s steps in a form aligned to claim 1: a first dose of 50 mg twice daily for 3 days; a second dose of 100 mg twice daily for 4 days; and optional further titrations at 150 mg, 200 mg, and 250 mg in minimum 3-day increments. The Delegate reasoned that D2 provided a clearly delineated pathway, and that a skilled reader would understand when to take each step. Where the first two doses did not sufficiently treat pain, the further steps were plainly to be followed. Accordingly, the full three-step titration of claim 1 was found to be disclosed by D2, not merely a two-step disclosure with an optional extension.
On somnolence, the Delegate applied the doctrine of inevitable result. The key reasoning at paragraph [57] was that the dosage regimen in D2 was generally intended to reduce the incidence of side effects, and the primary outcomes expressly included incidence of adverse events in general. While somnolence was not explicitly listed as a specific endpoint, it would inevitably be captured within the broader monitoring of adverse events. The Delegate held that the steps set out in D2 can only be carried out in a way that would fall within the scope of claim 1, including with respect to generating a lower level of somnolence. There was therefore no requirement for D2 to have explicitly hypothesised or tested for reduced somnolence. Treating pain with a lower level of somnolence was an inevitable result of following D2’s instructions. In the Delegate’s words: “…the disclosure of D2 anticipates all the steps that contribute to the medical use, it follows that it is not new medical use and therefore claim 1 is not novel.”
The Delegate grounded this reasoning in the test for anticipation from General Tire & Rubber Co v Firestone Tyre and Rubber Co Ltd [1972] RPC 457 — that if carrying out directions in a prior publication will inevitably result in something that would constitute infringement of a valid patent, that patent lacks novelty — and in the Full Federal Court’s holding in Mylan (supra), which confirmed that a clinical trial protocol containing only a hypothesis, without scientific proof or substantiated results, can nonetheless be an anticipatory disclosure.
On prolonged release formulation, the Delegate found that D2 explicitly referred to prolonged release tapentadol, although D2 did not disclose the details regarding how prolonged release is achieved are not within D2, and that the level of disclosure in D2 was equal to that in the patent itself, which similarly provided no further specific characterisation of the prolonged release form.
Consequently, at least claims 1 and 33 were found to lack novelty in light of D2.
Principles from these decisions
The following principles can be drawn from the Federal Court’s body of case law on this topic as well as application by the Australian Patent Office.
- Scope of prior art documents: Clinical trial protocols, participant information sheets, and consent forms publicly available before a patent’s priority date are capable of constituting prior art for the purposes of novelty under the Patents Act 1990 (Cth).
- Hypotheses can anticipate: A reasoned but unproven hypothesis in a clinical trial protocol can be novelty-destroying if it discloses the claimed invention with sufficient specificity. Scientific proof or validated efficacy data is not required for the disclosure to deprive a claim of novelty.
- The core question: The question remains simply what the prior document discloses, assessed against the essential features of the claimed invention.
- Divergence from UK/European law: Australia’s approach is different from that of the UK and Europe, where actual achievement of a therapeutic effect is required for anticipation of claim forms equivalent to method of treatment and Swiss-style claims. Australian law requires only that the drug was administered for the purpose of the claimed treatment. Method of treatment and Swiss-style claims are construed to be directed to a therapeutic purpose rather than a therapeutic effect. That is in Australia, it is not required that the prior art disclose a therapeutic effect or therapeutic efficacy per se to anticipate a method of treatment or Swiss-style claim – in contrast, it is the therapeutic purpose that is relevant. This position is more aligned with the US.
- Practical implications: Pharmaceutical patentees should treat all publicly disclosed clinical trial documents as potential novelty risks in Australia. Careful drafting of consent forms and protocols, and timely filing of patent applications, are essential to preserving patent rights in Australia.