In addition, Havas Sports and Entertainment/Cake Media picked up an award for Sainsbury's and Weber Shandwick was recognised for its GSK work.
None managed to pick up better than a Silver.
Overall, 11 Gold Lions were handed out in the PR category, to Germany (three), Italy (two), Sweden (two), US (two), Belgium (one) and Finland (one). The UK submitted 59 entries this year, the second highest of any country.
The US was the most active, nearly doubling the number of its submissions year on year from 46 to 82.
Last year, only two UK agencies won PR Lions: Resonate London and Weber Shandwick.
The new category was chaired by chairman and chief executive of Hill & Knowlton Paul Taaffe.
Also on the panel were managing director of Resonate Michael Frohlich and Weber Shandwick CEO for UK and Europe Colin Byrne.