How to change the value of a custom radio button field programmatically?
If the options that are shown on the profile are custom fields, then the radio options displayed might be the option values of some option groups.

To add/remove any options from the profile, you can make use of fieldOpions hook. Eg -

function hook_civicrm_fieldOptions($entity, $field, &amp;$options, $params) {
  //replace 1 with your custom address field id
  if ($field == 'custom_1') { 
    $options['my_option'] = 'My Custom Option';
  }
}


Check the doc for more info about the param, etc.