How to replace with an empty space all characters found with Regex?

Hi,

Variable_1 = Hello {world} this is a test

I need it to convert it into just: {world}

I will use regex ^(.*?)\{.*\}([^}]*)$ to identify all characters before the first { and after the last }.

How can I use regex_replace or any other function for that?

This is what I have in mind but is not working. I just want to know how to use the regex_replace in this case, assuming the regex is correct. No need to correct the regex, in case it is incorrect.