  We consider the planar MHV amplitude in N=4 supersymmetric Yang-Mills theory
for 2 -> 4 particle scattering at two and three loops in the Regge kinematics.
We perform an analytic continuation of two-loop result for the remainder
function found by Goncharov, Spradlin, Vergu and Volovich to the physical
region, where the remainder function does not vanish in the Regge limit. After
the continuation both the leading and the subleading in the logarithm of the
energy terms are extracted and analyzed. Using this result we calculate the
next-to-leading corrections to the impact factors required in the BFKL
approach. The BFKL technique was used to find the leading imaginary and real
parts of the remainder function at three loops.
