Run remote command

[rcasta74]

Hello,
is there a way to run a remote command without to start a shell?
It would be usefull with something like this:

ssh my-user@remote-host sudo su - tech-user

in this way, exiting as tech-user the session will end; it can be done with login scripts as well, but in that case a shell is started for both users; exiting as tech-user you will be still connected as my-user.

Thanks