A valve assembly comprises a closure element disposed in a flow control duct, a fluid-driven actuator assembly, a shaft operable to translate linear movement of the actuator assembly into rotation of the closure element, and an integral filter and pressure regulator unit disposed in line with an actuator fluid supply passage. The actuator fluid supply passage extends between the flow control duct and the actuator assembly. The integral filter and pressure regulator unit includes a regulator housing having at least one cylindrical wall surrounding a vent cavity and a regulator cavity. Filter media is secured to the regulator housing and is disposed across a regulator orifice in communication with the regulator cavity.