If the new deal is finally signed, Isco could earn around €6 million/year, although the length of this agreement has not been published just yet.
Isco's current contract with Real Madrid expires in 2018 and many teams in Europe were interested in his signing. Reports from Barcelona suggested that the player could have an early agreement to join Barça as a free agent.
It seems that the player could be willing to stay in the Spanish capital, although the new deal might not be announced until the end of this season. Isco has probably asked for a bigger role in the club as he wants to play in the 2018 FIFA World Cup.
It will be interesting to see what Zidane does with Isco's minutes during the rest of the season.