The Heroes star took the role of Knox in controversial 2011 Tv movie Amanda Knox: Murder on Trial in Italy while the American student was still in jail for the slaying.
Knox was set free later that year after a court in Italy overturned the verdict and quashed her murder conviction, and Panettiere has now spoken out to offer her sympathies to Kercher's family for any heartache her movie caused.
Panettiere tells British magazine Stella, "I can completely understand the feelings of the Kercher family... I apologise deeply for any pain that was inflicted. But I didn't do anything out of disrespect."
British student Kercher was found stabbed to death at her rented home in Perugia, Italy in 2007. Her housemate Knox and Knox's boyfriend Raffaele Sollecito were convicted of killing her during a kinky sex game but they were both freed on appeal in 2011.