Marvel Studios President Kevin Feige has indicated a Doctor Strange sequel hasn't been announced because of a desire to fulfill the promise of Phase Three before detailing future plans.
So far, all we know is that the Captain Marvel solo film and the untitled Avengers sequel will wrap Phase Three, with the Spider-Man: Homecoming sequel kicking off Phase Four in 2019.
"I feel like we’re still trying to fulfill the promise of that [Phase Three],” Feige told Vulture. “That’s what Infinity War is, that’s what Captain Marvel is and Ant-Man and The Wasp, and that’s what Avengers 4 will be. That’s what we have to do first, before we start saying, ‘And wait until you see this next thing!’ I don’t want to talk about what I’m having for dinner when I’m about to have lunch.”
“It’s not a time to announce the future stuff,” he continued, turning to why Marvel won't have a Hall H presence this summer at Comic-Con International. “Ant-Man and The Wasp will have just come out, Captain Marvel will have just finished filming … if we can’t over-deliver and really put on the kind of show we want to, then we think it’s better to save it until the next year.”
However, Feige assured that fans will get their fix of Benedict Cumberbatch's Sorcerer Supreme in the months to come. “We are getting a lot of Strange in Avengers: Infinity War," he said, "and he’s awesome."
Directed by Joe and Anthony Russo, Avengers: Infinity War stars Robert Downey Jr., Chris Evans, Chris Hemsworth, Mark Ruffalo, Jeremy Renner, Scarlett Johansson, Anthony Mackie, Paul Rudd, Elizabeth Olsen, Tom Holland, Benedict Cumberbatch, Chadwick Boseman, Chris Pratt, Zoe Saldana, Dave Bautista, Bradley Cooper, Vin Diesel, Tom Hiddleston, and Josh Brolin. The film arrives Friday worldwide.