It should work, see here:
[root@bugtestxb ~]# xtrabackup --user=root --password='supers3cretpa$$w0rd' --backup --target-dir backup/
170530 05:41:29 version_check Connecting to MySQL server with DSN 'dbi:mysql:;mysql_read_default_group=xtrabackup' as 'root' (using password: YES).
Failed to connect to MySQL server as DBD::mysql module is not installed at - line 1327.
170530 05:41:29 Connecting to MySQL server host: localhost, user: root, password: set, port: not set, socket: not set
[B]Using server version 5.7.18[/B]
xtrabackup version 2.4.7 based on MySQL server 5.7.13 Linux (x86_64) (revision id: 6f7a799)
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /var/lib/mysql
xtrabackup: open files limit requested 0, set to 1024
xtrabackup: using the following InnoDB configuration:
xtrabackup: innodb_data_home_dir = .
xtrabackup: innodb_data_file_path = ibdata1:12M:autoextend
xtrabackup: innodb_log_group_home_dir = ./
xtrabackup: innodb_log_files_in_group = 2
xtrabackup: innodb_log_file_size = 50331648
[root@bugtestxb ~]# rpm -qa|grep -i 'mysql\|percona'
perl-DBD-MySQL-4.023-5.el7.x86_64
mysql-community-libs-5.7.18-1.el7.x86_64
percona-xtrabackup-24-2.4.7-1.el7.x86_64
mysql-community-common-5.7.18-1.el7.x86_64
mysql-community-client-5.7.18-1.el7.x86_64
mysql-community-server-5.7.18-1.el7.x86_64