Wordpress: Custom post type active nav workaround

gistfile1.php

<?php

add_filter('nav_menu_css_class', function($classes, $item) {
    switch (get_query_var('post_type')) {
        case 'custom_post_type_name':
            if ($item->object_id == THE_ID_FOR_THE_NAV_ITEMS_TARGET_PAGE) {
                $classes = array_diff($classes, array('current_page_parent'));
            }
            break;
    }

    return $classes;
}, 10, 2);