A peristaltic pump assembly includes a pump body and a cassette removably attached thereto, wherein the cassette includes a race configured to provide a compression surface for a tube supported by the cassette. A roller assembly is operatively connected to the pump body, wherein the roller assembly includes a plurality of rollers configured to apply a predetermined force to the tube, thereby compressing the tube against the race. The peristaltic pump assembly further includes a regulator disposed in the pump body and operatively connected to the cassette, where the regulator is configured to regulate the predetermined force applied to the tube.