While there are a dozen+ similarly named and functioning arrangements between states, I think with NATO's current expansion the name of "North Atlantic" means less of a geographical limiter and more of a euphemism for "Western Aligned" countries.
For example, Georgia is a candidate member, and it's technically in both Asia & Europe.
There is the American–Japanese–Korean trilateral pact signed in 2023. The US and South Korea, Philippines, and Japan have bilateral defense treaties.
The US used to have treaty with Taiwan. There was proposed NEATO in the 50s, but Korea wasn't over WW2, and Japan is defense-only in constitution.
The big problem is that signing defense treaty with Taiwan would require change to the status quo and probably kick off a war.
For example, Georgia is a candidate member, and it's technically in both Asia & Europe.