A generalised It\=o formula for L\'evy-driven Volterra processes

We derive a generalised It\=o formula for stochastic processes which are constructed by a convolution of a deterministic kernel with a centred L\'evy process. This formula has a unifying character in the sense that it contains the classical It\=o formula for L\'evy processes as well as recent change-of-variable formulas for Gaussian processes such as fractional Brownian motion as special cases. Our result also covers fractional L\'evy processes (with Mandelbrot-Van Ness kernel) and a wide class of related processes for which such a generalised It\=o formula has not yet been available in the literature.