We investigate the regularity of the law of Wong-Zakai-type approximations for Itô stochastic differential equations. These approximations solve random differential equations where the diffusion coefficient is Wick-multiplied by the smoothed white noise. Using a criteria based on the Malliavin calculus we establish absolute continuity and a Fokker-Planck-type equation solved in the distributional sense by the density. The parabolic smoothing effect typical of the solutions of Itô equations is lacking in this approximated framework; therefore, in order to prove absolute continuity, the initial condition of the random differential equation needs to possess a density itself.
AMS 2000 classification: 60H10; 60H07; 60H30converges, as ε goes to zero, to the solution of the Stratonovich stochastic differential equation (SDE, for short)instead to the more popular Itô's interpretation of the corresponding stochastic equation, dX t = b(t, X t )dt + σ(t, X t )dB t .