$re = '/.*\)\s*(.*)\s*\([mf]\).*/';
$str = 'Dr. T. (Tom) Bailey (m), UCL- Physics
Dr. B.K. (Barbara) Blue (f), Oxford - Political Science';
$subst = "\1";
$result = preg_replace($re, $subst, $str);
echo "The result of the substitution is ".$result;
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