QCD factorization approach for heavy hadron decays introduces light-cone distribution amplitudes for heavy mesons and baryons as the main nonperturbative input. Evolution equations for these distributions have interesting properties under conformal transformations and are completely integrable for several
important cases which allows one to obtain explicit solutions.
The limit of large light quark energies in higher-twist distributions appears to be nontrivial. In this region the hierarchy of contributions with rising anomalous dimensions is lost and their resummation is mandatory.