Using pxrSurface or pxrDisney surface materials, you can render PBR outputs from Substance Designer and Substance Painter. Although pxrDisney is more straightforward since it support basecolor/roughness/metallic outputs directly, it is now a legacy material in Renderman and pxrSurface is the preferred method. 

For more information on pxrSurface, please refer to the Renderman documentation.