It would help to know your input data, and what you would like to match. In general you can escape meta characters by prepending a backslash, that should work fine.

The usual approach is this:

my $regex = qr{
     ^          # anchor
     \(         # opening paren
     ([^)]*)    # everything but a closing paren, captured in $1
     \)         # closing paren
     ,(.*)      # the rest, captured in $2
     $
}xs;
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