I did a little more reading on the drug and found that overall post menapausal bone recovery was the same for the weekly drug as for the annual.
The main reason for this drug is patient non-compliance, a high percentage stop taking the drug after one year of use. As you said, let the patient pay for the extra cost.
A quarter of women taking [Alendronate] go on to develop chronic side effects, including stomach pains, or do not respond to treatment.That could have something to do with the noncompliance . . .