  We study time-dependent deformations of a certain class of backgrounds in
type IIB supergravity. These backgrounds are solutions of a five-dimensional
consistent truncation, relevant for gauge/gravity duality, which have the form
of dS_4 foliations over a fifth (radial) direction. We investigate
time-dependent deformations of those solutions in the search for gravitational
duals of models of glueball inflation. A particular starting ansatz enables us
to find a class of analytical solutions, corresponding to an ultra-slow roll
inflationary regime. This regime may play a role in understanding the low l
anomaly in the power spectrum of the CMB.
