$re = '/(.+)\/brochure\?utm_campaign=(.+)/';
$str = 'https://acties.renault.nl/modellen/captur/brochure?utm_campaign=NL-r-t-NewCar-Captur-always-on-Feb-2017&utm_medium=Programmatic_buying&utm_source=Remarketing&utm_content=IAB&CAMPAIGN=NL-r-t-NL-r-t-NewCar-Captur-always-on-Feb-2017&ORIGIN=Programmatic_buying
';
$subst = "$1/?actie=brochure&utm_campaign=$2";
$result = preg_replace($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