With some Zen 2-based processors still in the pipeline, AMD confirmed that the design of the Zen 3 architecture is complete and the testing/manufacturing stages should soon follow. Even more, Zen 4 and Zen 5 are both being designed already and — if everything goes according to plan — the latter is set to arrive in 2022.
https://www.notebookcheck.net/Next-next-gen-Zen-5-architecture-is-already-in-development-confirms-AMD.439837.0.html