In our August 2021 article Can an Australian Patent Term Extension be Zero? we discussed the Federal Court finding that a patent term extension (PTE) could validly be found to be zero. The particular circumstances of that case, Merck Sharp & Dohme Corp. v Sandoz Pty Ltd [2021] FCA 947 (Merck) were that the patentee had achieved regulatory approval for two products, both of which fell within the scope of the same patent.

However, regulatory approval of the products had occurred at different times. The Patents Act 1990 (Act) is highly prescriptive, in essence requiring that to qualify for a PTE:

  • one or more pharmaceutical substances per se must in substance be disclosed in the complete specification of the patent and in substance fall within the scope of the claim or claims of that specification
  • goods containing, or consisting of, the substance must be included in the Australian Register of Therapeutic Goods (ARTG)
  • the period beginning on the date of the patent and ending on the first regulatory approval date for the substance, must be at least five years.

Of importance in that case was the requirement relating to “the first regulatory approval date”. Application of this requirement meant that the earliest regulatory approval date of the products had to be used to calculate a PTE. In this case it was found to be zero.

Whilst Merck remains on appeal with the Full Federal Court, the Australian Patent Office has been required to consider yet another example where the patentee has achieved regulatory approval for two products at different times.

Bayer Pharma Aktiengesellschaft [2022] APO 7 (7 February 2022)

Bayer had achieved regulatory approval for two products. YAZ® is a tablet which comprises 3 mg drospirenone and 0.02 mg ethinylestradiol. YASMIN® is a tablet which comprises 3 mg drospirenone and 0.03 mg ethinylestradiol.

YAZ® was approved on 8 February 2008. YASMIN® had been approved on 6 July 2001. Both products fell within the scope of claim 3 of patent no. 780330, which had a date of 20 August 2000. Consequently, the normal expiry date was 20 August 2020. However, based on the YAZ® approval, a PTE had been granted to 8 February 2023.

YAZ®/YASMIN® litigation

Patent 780330 had been enforced against Generic Health Pty Ltd. In the Full Federal Court, the finding of patent validity and infringement had been maintained (Generic Health Pty Ltd v Bayer Pharma Aktiengesellschaft [2014] FCAFC 73). For obvious reasons, the validity of the PTE was not raised.

Rectification of the Patent Register

Section 191A of the Act provides the Commissioner with the power to rectify the Patent Register. Specifically it states:

(1) The Commissioner may rectify the Register if the Commissioner is satisfied, on the balance of probabilities, whether on application or otherwise, of any of the following:

(a) the omission of an entry from the Register

(b) an entry made in the Register without sufficient cause

(c) an entry wrongly existing in the Register

(d) an error or defect in an entry in the Register.

The Patent Register includes particulars relating to an extended patent term.

Further, the Patent Regulations permit a rectification application to be made by “a person”. This is to be contrasted with a court ordered rectification where the requirement is for “a person aggrieved”.

The PTE entry for 780330 is rectified

An application to rectify the register entry for 780330 was made by the law firm, Bird & Bird. In essence, the rectification application disclosed the fact that YASMIN® had been approved on 6 July 2001 (the first regulatory approval date). Therefore any PTE based on this approval would be zero.

Based on the clear findings arising out of Merck, the Delegate of the Commissioner found that the Register should be rectified to show 780330 having an expiry date of 20 August 2020. As was the case in Merck, Bayer has an “of right” appeal to the Federal Court. But given the close factual similarity with Merck, the outcome of that appeal will have direct implications for Bayer. Presumably to maintain its position, Bayer will file an appeal by 7 March 2022.

A PTE strategy

We remain of the view that in a situation where multiple products will fall within the scope of a single patent, consideration should be given to covering each in separate patents by way of divisional applications. Australian patent law is relatively generous in its treatment of voluntary divisional applications. Specifically, an applicant has three months following acceptance (allowance) of an application within which to file a divisional application. This right is unfettered in that it is not dependant on a finding of multiple inventions.

Claim 3 of 780330 was in the following terms:

A pharmaceutical composition in oral dosage form comprising 3 mg of drospirenone and 0.01 mg to 0.05 mg of ethinylestradiol, together with one or more pharmaceutically acceptable carriers or excipients, wherein the oral dosage form is a table and wherein at least 70% of said drospirenone is dissolved from said composition within 30 minutes, as determined by USP XXIII paddle method II using 900 mL of water at 37 ̊C as the dissolution media and 50 rpm as the stirring rate.

Given that YAZ®/YASMIN® differed in ethinylestradiol content, claims in a parent and a divisional could have been limited to and 0.01 mg to 0.02 mg of ethinylestradiol and >0.02 mg to 0.05 mg of ethinylestradiol respectively.