Court of Appeal gets strict with priority in Novartis v Hospira (Part I)

The AmeriKat using a priority mail
box for it's intended purpose

The AmeriKat loves priority.  Priority access when flying means first dibs on the overhead bin compartments.  Priority mail appearing on her desk means something important which demands opening (like, hopefully, jewelry).  Priority in patent law allows a patentee to file a subsequent patent application for the same invention in another country but benefit from an earlier priority date and stave off any attacks on validity from later killer prior art.  Priority is a good thing but only if you have it, as today's Court of Appeal decision in Novartis v Hospira [2013] EWCA Civ 1663 demonstrates.  Giving judgment for the Court, Lord Justice Floyd held that Claim 7 of Novartis's patent was not entitled to priority from a US application and therefore the patent was invalid.

Background

Readers may remember the progeny of Novartis v Hospira cases from earlier this year in relation to, first, Hospira and then Generics (UK) Limited's revocation proceedings in relation to Novartis's EP (UK) 1 296 689  relating to the use of zoledronic acid (zoledronate in hydrated forms) for the treatment of osteoporosis.  Both parties wished to launch products falling within Claim 7 of the patent.

In March, Mr Justice Arnold held that the patent in suit and another related patent were invalid and that the loss of priority rendered Claim 7 invalid.  The parties also had a dispute about whether or not Novartis could benefit from an interim injunction pending appeal which also saw an outing in the Court of Appeal (see decision here).

Claim 7, which is dependent on Claim 5, claims the use of a zoledronate medicine for the treatment of osteoporosis where the medicine is adapted for intravenous administration in a unit dosage of approximately 2 - 10 mg of zoledronate and is administrated annually.   It covers Novartis's  ACLASTA, the first and only once-yearly bisphosphonate infusion product worth a reported $612 million annually.  Claim 7 claimed priority from US Patent Application No 267689 with a priority date of 20 June 2000.

The question before the Court of Appeal in this case was whether the US application disclosed the subject matter of claim 7.  The parties agreed that Claim 7 would be invalid if it was not entitled to priority because an intervening publication  - a 2001 publication in Bone (you know the one) - disclosed the invention.

The Court of Appeal held that Claim 7 contains, in combination, features directed to:

i.  The drug
ii.  The fact that the drug is for treatment of osteoporosis
iii.  The mode of administration (intravenous)
iv.  The range of dosage sizes (about 2-10 mg)
v.  The dosing interval (about once a year)

The US patent application discloses that:

• the invention relates to bisphosphonates (of which zoledronic acid is a member) for the use of abnormally increased bone turnover, such as osteoporosis
• the dosing interval for the present invention was "at least 6 months...or less frequently, conveniently once a year, or any interval in between....Dosing intervals of greater than once per year may be used." 
• the dosage size would depend on various factors, including the mode of administration as well as the ailment being treated:  "Normally, the dosage is such that a single dose of bisphosphonate active ingredient 0.005-20 mg/kg, especially 0.1-10 mg/kg, is administered..." Such a dosage would be typically administered intermittently with a period of at least 6 months or longer.
• the dosage size would also depend on the potency of the bisphosphonate and the dosing interval.
• for more potent, recent bisphosphonates such as zoledronic acid the application disclosed that "a unit dose of from about 1 up to 10 mg may be used...for dosing once every 6 months; whereas a dose of from about 2 up to about 10 mg may be used for once a year dosing."  This passage was referred to as the "2-10mg a year" passage and was the focus of the priority arguments in the appeal 
• intravenous administration is one preferred mode of administration
• Example 5 teaches that 4 mg, once a year, administered intravenously to patients with post-menopausal osteoporosis is effective

The High Court Decision

At first instance, Mr Justice Arnold held that there was nothing in the priority documenet linking zoledronate, osteoporosis, intravenous administration and administration at intervals of at least six months:

 "The nearest one gets is the abstract, which links zoledronate, osteoporosis and six monthly administration, but does not mention intravenous administration....As for Example 5, this is limited to the intravenous administration of particular doses of zoledronate to post-menopausal osteoporosis patients six months and yearly..."

Mr Justice Arnold held that in relation to the "2-10mg a year" passage, there was nothing to link it to intravenous administration.  The expert evidence indicated that some range would be expected to be appropriate for intravenous administration but that there was nothing specific in the passage to indicate that it related to or was effective for the treatment of osteoporosis by the intravenous administration.

On appeal, Novartis argued that Mr Justice Arnold failed to read the document as a whole.  Had he done so, he would not have failed to see the link between zolderonate, osteoporosis, and intravenous administration.  He had, instead, read each passage in isolation.

The law on priority

A road sign warning to all patentees to be
careful in narrowing the disclosure
from the priority document

Although the language of Article 87 of the European Patent Convention and Section 5 of the Patents Act 1977, which provide for the entitlement to an earlier priority date, is different they are taken to mean the same thing (Unilin Beheer [2008] EWCA 800).  The language of the Convention was interpreted as meaning that the priority of a previous application is to be acknowledged "only if the skilled person can derive the subject-matter of the claim directly and unambiguously, using common general knowledge, from the previous application as a whole." (Enlarged Board of Appeal in G2/98).

Priority can be lost by:

• narrowing down the disclosure from the priority document in a manner which the invention could not be derived directly and unambiguously from it (Pharmacia Corp v Merck & Co Inc [2002] RPC 41); or
• widening or generalizing from the priority disclosure (Beloit Technologies Inc and another v Valmet Paper Machinery Inc and another [1995] RPC 7005 and Unilin)

The story continues in Part II.