Leno joined Leverkusen in 2011 and has a £22m release clause in his contract.
The club have brought in Lukas Hradecky from Eintracht Frankfurt which could mean that Leno will leave during the summer.
But speaking recently, Leverkusen sporting director Rudi Voller said:
“Leno can leave but only on our terms.We are still in constant and open exchange with Bernd and his manager. Leno already had a concrete offer from Napoli in 2017, but we didn’t have an equivalent backup at the time.He had to stay and he did really well last season, but we thought Bernd’s desire to leave would resurface so and so with the arrival of Lukáš Hrádecký we have a high quality successor.”