I've just published version 10.34a of PCRE2 (Perl Compatible Regular Expressions) for z/OS. This is an interim release, while there is no change in the core library, we've introduced the 'substitute' functionality into the Rexx API.
The distribution is available on file939 of the CBTTAPE.org (currently, in the 'UPDATE' page) http://cbttape.org/ftp/updates/CBT939.zip) and eventually will move to the main page ( http://cbttape.org/ftp/cbt/CBT939.zip) in few months
The distribution includes a working simple API for Rexx and COBOL demo programs that demonstrates the usage in COBOL and other LE languages. The Rexx API includes an Assembler program that could also be used to demonstrate the usage from Assembler.