Should unapproved drugs be made available as a last resort to patients with conditions for which conventional treatments are known to be ineffective?

No way, their is a reason why it's an unapproved drug, one reason could be that it can caused death unpon taking the drug, another reason might be harsh effects to the body or major side effects. So I think its better to have a patient die from a natrual cause then to force them to take a unknown drug which isn't risk free, atleast this way your perpared for when the time comes and not regretting what you did.