Appeal No. 2004-2202 Page 8
Application No. 10/016,324
Thus, even assuming the references would have suggested administering Marshall’s
composition by inhalation, the method made obvious by the prior art would not be the
method of claim 29.
Mihalko discloses a method of administering a liposome-entrapped drug by
inhalation. See page 4, lines 21-26 (“[A] method for moderating the initial (short-term)
and extended (long-term) drug-level effects of a drug administered by inhalation. The
drug is provided in a form in which it is predomi[n]antly entrapped in the liposomes of a
liposome suspension.”). However, the examiner has pointed to nothing in Mihalko that
would have suggested the claim limitation requiring a “coating of hydrophilic polymer
chains on the liposome outer surface,” nor anything that would have suggested
combining one of the components of Marshall’s composition (e.g., PEG(5000)-DMPE) with
Mihalko’s liposomes. Thus, the examiner has not shown that Marshall supports a prima
facie case of obviousness, either alone or combined with Mihalko.
The examiner also rejected claim 29, among others, as obvious in view of
Mihalko and Klibanov. The examiner correctly noted that Mihalko teaches compositions
containing liposome-encapsulated drugs but does not teach “coating of the liposomal
surface with a hydrophilic polymer.” Examiner’s Answer, page 5. The examiner relied
on Klibanov for suggesting this limitation. See id.: “Klibanov teaches that when the
liposomal surface is coated with a hydrophilic layer of oligosaccharides, glycoproteins,
polysaccharides and synthetic polymers such as PEG, the liposomes avoid the RES
[reticuloendothelial system] and circulate in the blood for longer periods.”
The examiner concluded that to “coat the liposomes of [Mihalko] with a
hydrophilic polymer would have been obvious to one of ordinary skill in the art because
Page: Previous 1 2 3 4 5 6 7 8 9 10 11 12 13 Next
Last modified: November 3, 2007