$re = '/[:=]\s*([\w\s]*)/';
$str = 'SOMETEXT: ANYTHING_HERE (Old=ANYTHING_HERE, New=ANYTHING_HERE)
ABC: Some_Field (Old=,New=123)
ABC: Some_Field (Old=ABCde,New=1234)
ABC: Some_Field (Old=Hello World,New=Bye Bye World)';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php