Production amplitudes at the multi-Regge kinematics in QCD and in N=4 SUSY

We review the BFKL approach based on the use of the analyticity and unitarity for high energy production amplitudes in the multi-Regge kinematics for final states particles. In particular, the Pomeron is a composite state of reggeized gluons. The BFKL dynamics turns out to be integrable at large Nc. In N=4 SUSY the Pomeron is equivalent to a reggeized graviton. We show, that the production amplitudes suggested by Bern, Dixon and Smirnov for this model do not contain the Mandelstam cuts. It turns out, that the corresponding composite states are described by the hamiltonian of an integrable open Heisenberg spin chain.