I believe escape to be the cuplrit IMO. What escape patterns did you use? I think you will need a double escape like regexp: "/^\\/\\/PROD.*/"
And just to be sure, make sure you are using " (straight quotes) and not “ or ” (angled quotes), but that is probably just your text formatter in this question.
P.S. you can format your code blocks by putting ``` on a blank line before and after the block 