Do the claims include atorvastatin?
Ranbaxy had contended that the structural formula in the claims of the 981 Patent could only be construed as relating to an equal mixture (racemate) of the two ‘R’ and ‘S’ enantiomer types for that class of compounds, as the method disclosed in the patent specification would produce racemates only. According to this construction, atorvastatin, which is the R enantiomer only, would be outside the scope of the claims. The Full Court upheld the decision of the judge at first instance that the claims, when read in the context of the specification of the 981 Patent, related to equal and unequal mixtures of enantiomers as well as the individual enantiomers. In reaching this conclusion, the court relied on expert evidence on what would have been the common general knowledge of a synthetic organic chemist in 1986. This was relevantly found to have included an assumption that the ‘R’ enantiomer was likely to be the active or more active enantiomer, and a knowledge of various techniques for sepa
