Material exchange between a planet and its host

Of the exoplanets found so far, is there one that can exchange material with its host? How could we prove that?

Io might be a good example, but it is not a planet.

The mass loss rate $\dot{M}$ should be approximately $$\dot{M}\sim\frac{\dot{E}_tR_p}{2GM_p}$$ where $R_p$ and $M_p$ are the radius and mass of the planet, and $\dot{E}_t$ is the tidal heating rate, given as $$\dot{E}_t\sim\frac{e^2GM_pM_*}{a\tau_e}$$ for stellar mass $M_*$, semi-major axie $a$ and characteristic eccentricity damping timescale $\tau_e$.