Dear Daisuke-san,
Yes, it is possible. The control file for REMD simulations using GBSA is very similar to those for explicit solvent systems. In this website, you can find example control files for conventional MD simulations using GBSA (Tutorial 8.1) and also REMD simulations for explicit solvent systems (Tutorial 10.2). All you have to do is just add the [REMD] section in the control file for the conventional MD with GBSA.
Bests,
Takaharu Mori