Nah, this will never happen. Always been a big fan of the franchise and kept track on the "stories".

There was a story that Michael J. Fox was interested in playing Doc in a 4th film, with a new younger cast being added. But due to health problems, it just won't happen.

Plus, the Delorean was destroyed in the 3rd film,......who the hell wants to watch a film about a time travelling locomotive?!?!

But Ghostbusters 3 is deffo happening!!!