Lyon racked up an impressive seventh win from as many Top 14 matches this season and champions Toulouse earned a timely win against Castres.
Jean-Marc Doussain impressed with the boot, kicking 17 points as Lyon outclassed Pau 27-8 at the Matmut Stadium.
Rudi Wulf scored a first-minute try and Baptiste Couilloud also touched down in an easy victory for the hosts.
Thomas Ramos was a surprise inclusion for Toulouse despite having been ruled out of the Rugby World Cup for France last week and was part of a team that saw off Castres 36-15.
Zack Holmes nailed 21 points with the boot, while Matthis Lebel, Lucas Tauzin and Gillian Galan scored tries as Toulouse jumped from 13th to seventh.
In other matches, third-placed Bayonne edged Montpellier 28-24, La Rochelle crushed struggling Brive 41-17 and Racing 92 drew 27-27 with Agen.