Oral bisphosphonates need to be contra-indicated, poorly tolerated or radiologically proven to be inefficacious in order for the patient to be eligible for Denosumab.
If Denosumab is being used to treat osteoporosis I do believe it's still only licenced for treatment in women at 60mg subcutaneously ever 6 months.
If being used to treat bone mets, it is licenced for men and women at 120mg every 4 weeks.
It can only be initiated for osteoporosis by someone with a special interest in osteoporosis.