string – converting the SQL regexp to sas prxchange

I have a SQL code with some lines of REGEXP_REPLACE function to clean a string. I am trying to re-write the code in SAS using the PRXCHANGE function. However having problem understanding what the patterns mean in SAS. could anyone help on translating the pattern to SAS version.

REGEXP_REPLACE(string,'([0-9]+[/][0-9]+[/][0-9]+|[#][A-Z0-9]+|ON.*|[\d]+\s+[\d]+\s+[\d]+)','','inm')

or

REGEXP_REPLACE(full string,'(ON[0-9]+[/][0-9]+[/][0-9]+|REF [#][A-Z0-9]+)|ON.*','','inm')

In SAS I tried PRXCHAGNE("s/(same pattern as SQL)//in", -1, full string) which gave me error due to invalid character. Potentially pattern in SQL is not readable by SAS and need to be revised. Your help is appreciated in advance.