Teva UK Ltd & Anor v Astrazeneca AB (Rev 1)

A patent for using a formoterol and budesonide combination inhaler for both asthma maintenance and relief was invalid for obviousness. The skilled person would have regarded the combination as an obvious approach to try, with a reasonable or fair expectation of success, having regard to the prior disclosure and common general knowledge. The absence of phase 3 safety trials did not make the idea inventive. Nor did later-observed benefits, including improved compliance, supply the necessary technical contribution where the patent disclosed no reason to expect them.

Amendments based on dosage details extracted from an illustrative example added matter through impermissible intermediate generalisation. The amended claims were also obvious.

Teva brought a revocation action concerning AstraZeneca’s patent for SMART asthma therapy, involving formoterol and budesonide used for regular maintenance and as-needed relief. AstraZeneca brought a related infringement action after Teva obtained marketing authorisations for products said to fall within the patent.

The court considered anticipation by an earlier 1993 patent, obviousness in light of that patent and the common general knowledge, and AstraZeneca’s proposed amendments concerning dosage regimes. No infringement issue required determination at that stage. The central questions were whether the claimed therapy was clearly and unambiguously disclosed in the earlier patent, whether it was obvious to the skilled person at the priority date, and whether the amendments were allowable.

1. Anticipation. The 1993 patent did not clearly and unambiguously disclose use of the formoterol and budesonide combination for both maintenance and relief therapy. Its references to rapid relief and rescue were properly understood in the context of twice-daily maintenance treatment and associated compliance benefits. Teva’s anticipation challenge therefore failed.
2. Obviousness. Applying the four-stage approach in Pozzoli Spa v BDMO SA [2007] EWCA Civ 588, the relevant skilled person was a clinician with a specialist interest in asthma management. The common general knowledge included the rapid onset of formoterol, its use with inhaled corticosteroids for maintenance, combination inhalers, and the importance of treatment compliance. Routine literature searching could also form part of common general knowledge where the background knowledge made relevant published material likely to be found.
3. The 1993 patent disclosed combination maintenance therapy and a rescue effect. The gap between that disclosure and the claimed SMART therapy was bridged by the common general knowledge in 1998. It was obvious to pursue the approach with a reasonable or fair expectation of success. The absence of completed phase 3 safety trials affected adoption and regulatory acceptance, not the obviousness of the idea.
4. The patent disclosed no novel technical reason why the claimed therapy would be safe or effective beyond what was already known. Improved compliance and so-called self-correction were predictable consequences, not an additional inventive contribution. The patent was therefore invalid under section 72 of the Patents Act 1977.
5. Amendments. The amendments were sufficiently clear. In context, “unit dose” meant the delivered dose rather than the metered quantity placed in an inhaler. However, extracting dosage details from Example 5 and presenting them as general claim limitations amounted to intermediate generalisation and added matter contrary to section 76(3)(a). The narrower claims also made no distinct technical contribution and remained obvious. Each proposed amendment was rejected.
6. Teva’s obviousness challenge succeeded on the basis of the 1993 patent read in the light of the common general knowledge. The patent was invalid and the amended claims were not allowed.