$re = '/( *)("Description".*?CCGcode.*?<td>)([^<]+)/';
$str = '"properties": {
"Name": "Darlington",
"Description": "<br><br><br> <table border=\\"1\\" padding=\\"0\\"> <tr><td>CCGcode</td><td>00C</td></tr> <tr><td>CCGname_short</td><td>Darlington</td></tr>"
}';
$subst = "\1\"CCGcode\": \"\3\",\n\1\2";
$result = preg_replace($re, $subst, $str, 1);
echo "The result of the substitution is ".$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