A combustion engine includes, a first controllable engine valve (8) arranged to selectively open/close a combustion chamber (7) included in the combustion engine (1), and a gas handling system arranged to drive the first engine valve (8), which gas handling system includes a closed pneumatic pressure fluid circuit, wherein the closed pressure fluid circuit includes, coupled in series with each other, a compressor (31) and a valve actuator (10) that are operatively connected to the first engine valve (8). The combustion engine is characterized by the gas handling system further including a gas accumulator (38) that is connected with the closed pressure fluid circuit via at least one gas accumulator conduit (39), which includes a controllable valve (40). A gas handling system for pneumatic control of a valve actuator is also described.