Megan Lee had eaten at the Royal Spice Indian takeaway on Union Road on 30 December before suffering an apparent allergic reaction.
The 15-year-old, from Oswaldtwistle in England, was admitted to hospital but died two days later.
Lancashire Police said a post mortem examination had taken place but full results were not yet known.
It added investigations were continuing with Trading Standards and Environmental Health.
The men, aged 37 from Rossendale and 38 from Blackburn, were arrested on suspicion of involuntary manslaughter by gross negligence and have been bailed until July 2017.
They are believed to be employees at the takeaway.
"Our thoughts are with Megan Lee's family. [Please] take care with takeaway food if you have a severe food allergy," said the Anaphylaxis Campaign on Twitter.
The UK charity supports people at risk from severe allergic reactions (anaphylaxis).