Sorting custom archives by multiple custom fields

Hi,

I have a custom template page to display a custom post type archive. I am sorting by a custom field, but would like to sort by two custom fields.

I am using the below code in my custom functions, to pre sort the custom_post_type_1 archive page by cpt_tracking_lead (a custom field).

function sort_my_cpt( $query ) {
if ( is_post_type_archive( 'custom_post_type_1') ) {
$query->set('meta_key', 'cpt_tracking_lead');
$query->set('orderby', 'meta_value');
$query->set('order', 'ASC');
return;
}
}
add_filter( 'pre_get_posts', 'sort_my_cpt', 1);

This works great for sorting the archive list by the cpt_tracking_lead assigned to the post, but I would like to add another sort, by the post title. I can only figure out how to do one or the other. Can you please help me understand if I can add two meta sorting keys?

Thank you!

Aurelio