So Prolia is a new drug and it's innovative in that it's the first directed human immunoglobulin
monoclonal antibody.
So it's actually working on the immune system and what it does is it interferes with this
protein called RANK-Ligand protein, which actually affects osteoclasts and it actually
prevents their formation and maturation and their survival rates and so what happens really
is that Prolia is working by affecting the whole remodelling of bone.
It's actually similar in mechanism of action to the bisphosphonates that everyone is most
familiar with, but this is working on the immune system and that sort of mechanism whereas
bisphosphonates are more of a chemical interaction, so it's very, very different, but similar
in mechanism of action to bisphosphonates but it's working on the immune system.
Again, there have been several large studies showing significant benefits, both to fracture
rates and improvements in bone density.
It's been compared in one study to the bisphosphonate Alendronate and again it's shown superior
results in fracture and bone density to the bisphosphonates.
Of course, of concern is the more serious potential where there's potential lowering
of blood calcium, higher rates of infections, even higher rates of skin problems.
And also in several of these studies higher rates of cancer, but not being significant
at this point.
This is of course the concern, is that it's working in a new way, it's interfering with
the immune system, which of course has a role, particularly those very important cells called
T-lymphocytes, which are very important in the immune system.
So is it increasing rates of infections or cancers or some other conditions that we weren't
aware of and that we have only a 3-year study, so the longest it's been studied is 3 years
and there's some extensions of the existing study, which are going as long as 5 years.
Absolutely, that's the big concern isn't it?
What is happening in the long term with this drug.
I think this is what happened with the bisphosphonates is you have this migration to preventative
to people who are at very low risk of an actual fracture being prescribed drugs preventatively.
We really want to be cautious with Prolia, which is a new mechanism of action which affects
immune system, which has potentially some serious, long-term effects which we aren't
aware of over time.
That it is absolutely used in people who are at the most risk of actually having a fracture.
People that have high risk of an actual osteoporotic fracture and that it is not used until more
data is available in people who are at low to moderate risk or no risk or being used
preventatively.
So when I use that word of concern I think that's very, very strong, but I think it's
really important that people use it appropriately and they're using other very well established
and safe treatments for mild to moderate or prevention, which is exercise and nutrition.
In the drug-only options I think certainly it's more effective in the current studies
than bisphosphonates.
It's certainly not as powerful as Forteo, but it has some advantages in that it doesn't
interact with some other drugs, it doesn't have some of the esophageal effects, it's
very convenient in dosing and it seems to have very little effects in terms of problems
with respect to kidney clearance and liver function, so it has kind of unique profile.
The big concern of course, is what is it doing in the long term and is it being reserved
for currently at-risk patients.
So you don't want to cause all these problems long term that are more dangerous than the
actual drug, the risk of a fracture, so that's the main concern.
When people are arriving here, we're looking at all their drugs, insuring that there's
not other agents that are interfering with their bone density.
We want to make sure that they're using a superior exercise program.
We do assessments and measure their actual vitamin D levels, so that it's not left to
chance.
Because they are variations in absorption of vitamin D, so we insure that all our clients
are above 100 nanamoles per liter of 25-hydroxy vitamin D.
We establish adequate calcium intake at a minimum of 500 milligrams per day.
We assess other nutrients, and other functions in the body that have been proven to increase
bone density.
So we're trying to create a very holistic approach in our recommendations.