Correct comma use in the following sentence

I have received an email containing the following sentence:

"Many thanks for your prompt response John, this is really helpful."

My questions is: should there be an additional comma before John so as to read "Many thanks for your prompt response, John, this is really helpful."?

To give some context John is the only person who has provided a prompt response and would be identifiable as the intended recipient without using his name.

Many thanks.