Of course. So the time dependent looks like
i \hbar{\partial \over \partial t} \phi(p,\,t) = \hat H \phi(p,\,t)
and for
\hat H=\sqrt{p^2c^2+m^2c^4}
it gives
\phi(p,\,t) = \phi(p,\,0)e^{-i\sqrt{p^2c^2+m^2c^4}t/\hbar}
which would lead to (by the previous reasoning)...