The global Lipitor patent battle
Despite litigation in at least ten
jurisdictions across the world, Ranbaxy has so far been unable to obtain launch before
patent expiry (~2011). (Further
On 28 June 2006, the United Kingdom
Court of Appeal handed down its decision in Ranbaxy (UK) Ltd. v Warner-Lambert Company Rev 1  EWCA Civ 876.
In essence, the UK Court of Appeal
held that the basic patent was infringed by the R, R enantiomer,
but the enantiomer patent was not novel and invalid. Thus, (barring a successful appeal to the
House of Lords), Ranbaxy will be unable to launch generic Atorvastatin (Lipitor) in the United Kingdom until 2011.
patent families have been in issue in the various proceedings around the
world (other, process patents have also been litigated in some
countries). The first key family
derives priority from US19860868867
andclaims a racemic mixture of enantiomers of
Atorvastatin (‘the basic patent’). The second key family derives priority from
claims the calcium salt of the R, R enantiomer of Atorvastatin (‘the enantiomer patent’).
The pattern of litigation does not suggest
a coordinated, strategic attack by Ranbaxy.
Given the overwhelming lack of success to date, it is difficult to see
what Ranbaxy hopes to achieve in continuing the litigation.
A trite answer (which may be all
that is needed), is that given the size of the market for Lipitor, success in
even one moderately-sized jurisdiction will more than pay for all of the
Clearly, Lipitor illustrates this
important principle, which should be factored into global litigation strategy
along with other key factors such as cost and time to first judgment (see my article ‘Value for money in global patent litigation: Relative cost
and time to first judgment in eight key countries’).
What happened in the UK?
relation to the basic patent, the UK Court of Appeal held that the R, R
enantiomer infringed claims which depicted the racemic mixture. This finding was based substantially on the
common general knowledge of the skilled addressee of the patent, which
included knowledge that the molecule would have two chiral centres,
that other molecules in the class (Statins) had
at least one chiral centre and that the R, R enantiomers would be more active
and readily separable.
Court of Appeal held that the enantiomer patent was not novel in light of
earlier filed WO 89/07598.
This was essentially because the R, R enantiomer had been prior
disclosed in the following terms “The preferred isomer in this invention
is the 4R,6R-isomer of the compounds of Formulas I, Ia and XII above”
and the patent clearly taught that (amongst others), the Calcium salt could
be made. To quote Pumfrey J from the
first instance decision:
is no answer to an allegation of anticipation that the specification gives
clear and unmistakable directions to use the common general knowledge to
produce a specific material.”
Court of Appeal saw no need to also determine obviousness of the enantiomer
patent which it held invalid. (As the Court
of Appeal mentioned, it is extremely unlikely that leave to appeal to the
House of Lords would be granted, and that this Appeal would be
overturned. (See — Synthon BV v SmithKline Beecham Plc  UKHL 59.) If that happened, then the case would be
remitted to the Court of Appeal to determine obviousness as well.)
UK appeal was from the judgment of Punfrey J in Ranbaxy (UK) Ltd. v Warner-Lambert Company Rev  EWHC
2142 (Pat),  FSR 14.
that case, Pumfrey J refused Ranbaxy’s application for a declaration of
non-infringement of Warner-Lambert’s EP (UK) 0 247 633 (basic patent) but held Warner-Lambert’s
EP (UK) 0 409 281 (enantiomer patent)
invalid for lack of novelty and obviousness.