How to retrieve the list and count of users based on the isDisabled field from Eloqua API?

Currently we have an endpoint to retrieve the list of users, but there isn't any specifically to retrieve enabled/disabled users. The API does return a field called 'isDisabled' for every user, but I am unable to retrieve users based on the 'isDisabled' field.

Eg: /api/REST/2.0/system/users?search=isDisabled='True'

The above API returns all the users (both enabled and disabled).

Please suggest a way to achieve the above.