According to Variety, Stallone was headed for a fifth Rambo film, but has had a change of heart and will finally retire from the series stating:
"The heart’s willing, but the body says, ‘Stay home!' It’s like fighters that go back for one last round and get clobbered. Leave it to someone else."
Supposedly titled Last Blood: Rambo, the 69-year-old actor has apparently changed his mind. Stallone also added:
"There’s nothing left. When they asked me to do another ‘Rambo,’ I said, ‘If I can’t do better than I did last time, and I can’t, then why?'"
Currently there is a Rambo TV series in development at FOX. This series is going to focus on Rambo's son. However, Stallone will not have any role in this TV series.
The most recent you've probably seen Sylvester Stallone was in Creed, reprising his role as Rocky Balboa. He's also attached to an Expendables TV series, also in development at FOX, as well as another Expendables movie, which will reportedly star Hulk Hogan, Pierce Brosnan and much more! He's not done just yet!
Some information gathered from IGN