  We study anisotropic inflationary solutions when the inflaton and its
derivative couple to a vector field. This type of coupling is motivated by
D-brane inflationary models, in which the inflaton, and a vector field living
on the D-brane, couple disformally (derivatively). We start by studying a
phenomenological model where we show the existence of anisotropic solutions and
demonstrate their stability via a dynamical system analysis. Compared to the
case without a derivative coupling, the anisotropy is reduced and thus can be
made consistent with current limits, while the value of the slow-roll parameter
remains almost unchanged. We also discuss solutions for more general cases,
including D-brane like couplings.
