How to change variable name from known string?

Given: I have variable "Old_var=55" and string "New_var".

Want: How to change name from Old_var to New_var by using code, so I will have new variable "New_var=55".

[Stephen23]

https://www.mathworks.com/help/matlab/matlab_prog/string-evaluation.html

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Answer 1

[Azzi Abdelmalek]

assignin('base',Old_var,'New_var')

[Ivan Shorokhov]

Thank you, but another way around.

assignin('base','New_var', Old_var )