In Apotex Pty Ltd v ICOS Corporation [2017] FCA 466, the Federal Court has provided guidance regarding the level of disclosure required by a patentee in order for a court to exercise its discretion in allowing amendments to the specification during court proceedings.

Eli Lilly and Company (Lilly) is the holding company of ICOS Corporation (ICOS) and holds a number of patents worldwide that relate to a compound known as tadalafil (a PDE5 inhibitor that is useful in the treatment of erectile dysfunction).

As part of a Federal Court proceeding brought by Apotex relating to the validity of AU 773666 (the "666 Patent", relating to compositions containing tadalafil, including in micronised particle sizes, and methods of treatment using such compositions) and the AU 769946 (the "946 Patent", relating to compositions containing particular daily dosages of tadalafil for oral administration and methods of treatment using such dosages), ICOS sought orders to amend the specifications of the patents under s105(1) of the Patents Act 1990 (which deals with court-directed amendments).

The proposed amendments to the 666 Patent involved the addition of 15 dependent claims directed to specific doses or dosage ranges of tadalafil. The purpose of these amendments was to strengthen ICOS's defence to Apotex's inventive step challenge.

The proposed amendments to the 946 Patent involved removing statements in the specification concerning the side effect profile of tadalafil when co-administered with organic nitrates. One of the grounds of invalidity raised by Apotex was inutility on the basis that tadalafil did not eliminate particular side effects, or reduce them to clinically insignificant levels, when co-administered with an organic nitrate. The purpose of the amendments was to strengthen ICOS's defence to Apotex's utility challenge by removing any promises that could be found to have not been met (in Ronneby Road Pty Ltd v ESCO Corporation [2016] FCA 588, Jessup J found that failure of one of the promised results, even though others were attained, could give rise to revocation for inutility).

Apotex opposed the amendments for both the 666 Patent and the 946 Patent, arguing that ICOS had failed to make full disclosure of all relevant matters relating to the proposed amendments, that it had unreasonably delayed the proposed amendments, and that it had not adequately explained the reasons for the proposed amendments (Apotex subsequently withdrew their opposition to the amendments for the 666 Patent).

The Commissioner of Patents found that the amendments to the 666 Patent and the 946 Patent met the requirements of s102 of the Act (which deals with amendments which are not allowable). As such, the only issue was whether the amendments should be allowed in the exercise of the Court's discretion.

The relevant principles in relation to an application to amend a patent under s105(1) have been previously summarised by the Full Federal Court in Laboratoires Servier v Apotex Pty Ltd [2016] FCAFC 27; (2016) 117 IPR 415. In that case, the Court refused to allow the patentee to amend its specification to overcome a failure to describe the best known method of working the invention. The relevant principles established in that case were:

  • the onus to establish that amendment should be allowed is on the patentee;
  • generally, a permissible amendment (i.e. one which is permitted under s102 of the Act) will be allowed unless there are circumstances which would lead the court to refuse amendment;
  • the patentee must make full disclosure of all relevant matters;
  • amendment should be sought promptly and where a patentee delays for an unreasonable period, the patentee has the onus of showing that it delayed on reasonable grounds;
  • unreasonable delay is a circumstance likely to lead to refusal of an amendment;
  • in assessing delay, the relevant time is from when the patentee knows of the likely invalidity, or has its attention drawn to a defect in the patent, or is advised to strengthen the patent by amendment;
  • mere delay is not, of itself, sufficient to refuse to exercise the discretion to amend. The fact of delay is, however, relevant to whether the respondent or the general public have suffered detriment; and
  • if a patentee seeks to take unfair advantage of the unamended patent, knowing that it requires amendment, then refusal of the amendment is likely.

ICOS relied on affidavits sworn by Mr Gary Cox (lawyer and patent attorney at Wrays, acting for ICOS), Dr Mark Stewart (patent attorney at Lilly), Mr Danny Wood (patent attorney at Lilly), and Dr Malcolm Mitchel (formerly Medical Director at Lilly) setting out, in detail, the reasons for the proposed amendments to the 666 Patent and the 946 Patent, and the timing of events leading up to the application to amend. ICOS also provided verified discovery which included emails between Wrays and Lilly, emails between internal Lilly patent counsel and Lilly's clinical study reports. ICOS did not maintain a claim for privilege in respect of these documents.

The Court found that ICOS's conduct was reasonable, that it had made full disclosure and that there had been no unreasonable delay in seeking to amend the specifications of the the 666 Patent and the 946 Patent. The Court also found that there was no evidence that Apotex would suffer any prejudice if the amendments were allowed, other than the possible effect on its utility challenge. Apotex had given an undertaking not to market, sell or exploit its generic tadalafil products during the term of AU 689205 (Lily's tadalafil composition patent), so the patents which ICOS sought to amend had not been instrumental in Apotex refraining from entering the market. In addition, the Court noted that the application to amend had been made before trial, and that no third party had sought to oppose the application to amend.

Apotex identified four matters which it submitted were relevant to the Court's exercise of its discretion.

Firstly, Apotex submitted that the amendments to the 946 Patent did not involve a narrowing of the claims so as to avoid an argument based on a piece of prior art. Rather, they involved the removal of statements about the co-administration of tadalafil and organic nitrates. Apotex submitted that the obligation to make promises that were met or could be met crystallised on the filing of the patent application or, in the alternative, on the grant of the patent. However, the Court found that unlike best method and sufficiency, the patentee was not required to make statements regarding the utility of the invention, so that no such obligation crystallised on filing.

Secondly, Apotex argued that ICOS's conduct in relying on statements about the co administration of tadalafil and organic nitrates in correspondence with the Commissioner of Patents during prosecution of the 946 Patent should be taken into account and was a reason not to allow the amendments. However, the Court was not satisfied that the statements made by ICOS during prosecution were material in overcoming the objections raised by the examiner.

Thirdly, Apotex argued that the amendments sought by ICOS involved the removal of the main promises in the 946 Patent. However, the Court found that while the statements about the co-administration of tadalafil and organic nitrates were an important aspect of the specification, they were not the only advantage identified.

Fourthly, Apotex argued that the 946 Patent is a selection patent and that the advantages of the selected members are critical to the validity of the patent. However, the Court found that even if the 946 Patent is a selection patent and the amendments are allowed, a number of advantages or benefits of the invention remain in the specification.

The Court was not satisfied that the matters identified by Apotex warranted a refusal of the application to amend. Consequently the Court directed that, pursuant to s105(1), the complete specification of the 666 Patent and the 946 Patent be amended. The invalidity trial is listed for June 2017 and Spruson & Ferguson will keep you informed of developments.

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