Appeal 2007-2212
Application 10/667,472
The efficiency of respiratory drug delivery is largely determined by the
particle size distribution. (Id.) Large particles (greater than 10 m) are
primarily deposited on the back of the throat. (Id.) Greater than 60% of the
particles with sizes between 1 and 10 m pass with the air stream into the
upper bronchial region of the lung where most are deposited. (Id.) With
particles less than about 1 µm, essentially all of the particles enter the lungs
and pass into the peripheral alveolar region; however, about 70% are
exhaled and therefore are lost. (Id.)
Appellants claim a nanoparticulate composition comprising:
beclomethasone dipropionate particles having an average particle size of less
than about 1000 nm; and at least one surface modifier.
Obviousness
Claims 10-22 and 24-26 stand rejected under 35 U.S.C. § 103(a) as
obvious over Liversidge in view of Drug Information Handbook (Drug).
The Examiner finds
Liversidge et al teach dispersible particles consisting
essentially of a crystalline drug substance having a surface
modifier adsorbed on the surface thereof in an amount sufficient
to maintain an effective average particle size of less than about
400 nm (see abstract and col. 1, lines 32-43). . . . Suitable drugs
include corticosteroids, such as steroid A. The surface
modifiers can be selected from the group including non-ionic
and anionic surfactants such as polyvinylpyrrolidone (see cols.
3-4).
Liversidge also discloses that the effective average
particle size of less than 400 nm, or less than 100 nm is
preferred. Also at least 99% of the particles have a particle size
less than the effective average, eg. 400 nm (see col. 5, lines 26-
40).
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Last modified: September 9, 2013