Denosumab (Prolia)
Prolia (denosumab) is a biologic medicine used to treat and prevent thinning of the bones (called osteoporosis) and other diseases where loss of bone mass is a concern.
Prolia is a type of protein called a monoclonal antibody that works by disrupting a natural process in the body that breaks down the bones. This gives a different natural process that builds up the bones a chance to get ahead and build up bone density.
Taking Prolia
Prolia is available in a pre-filled syringe with a normal dose of 60 mg. It is taken once every 6 months by injection. The injection is usually given by a doctor or nurse.
To help build the bones, patients should take calcium and vitamin D while taking Prolia. Doctors will tell their patients the right amount of calcium and vitamin D to take. Patients should take any supplements exactly as prescribed by their doctor.
Important Tests and Risks
Doctors need to monitor the response of patients taking Prolia. This is done with a Bone Mineral Density test, usually once every 1 to 3 years.
Prolia can make it a bit harder to fight infections. Patients who develop a fever or think they have an infection are advised to tell their doctor.
Prolia been associated with a very rare problem with the jaw called osteonecrosis. This problem is sometimes seen after dental work. Patients should let their doctor know if they develop sudden pain in the jaw.
Alcohol is known to increase fracture risk by decreasing bone mineral density and promoting osteoperosis.
Patients who are prescribed Prolia should stop drinking alcohol, or at least significantly reduce the amount of alcohol that they drink.
Science
The body features an ongoing process called bone remodeling where bones are constantly broken down (bone resorption) and rebuilt.
Bones are broken down by a type of cell called osteoclasts and are built back up by a type of cell called osteoblasts.
In patients with osteoporosis, too much bone is being broken down too quickly.
Before osteoclasts mature and are able to break down bone, they are called pre-osteoclasts. These pre-osteoclasts have a specific receptor on their cell surface called RANK (Receptor Activator of Nuclear factor Kappa B). When RANK is switched “on” by a protein called RANKL (RANK-Ligand), it causes the pre-osteoclasts to mature into bone-dissolving osteoclasts.
Prolia is a protein called a monoclonal antibody that binds to RANK-Ligand. This prevents the RANK-Ligand from binding to pre-osteoclasts, and thus prevents them from maturing into osteoclasts. The effect is that the bone resorption process is slowed down, and the body has more time to build up and strengthen its bones.
The body makes a substance called osteoprotegerin that does a similar thing to Prolia by preventing pre-osteoclasts from maturing into osteoclasts. In some patients with osteoporosis, this substance is found in lower concentrations and this is partly why their bones break down too quickly.
Safety
Patients taking Prolia should talk to their doctor if they are concerned about any side effects.
The most common side effect of this medication are rashes and issues with the skin.
Patients should let their doctor know if they develop a rash while taking Prolia, develop jaw pain, or experience muscle cramps, twitching or weakness.
Possible side effects include:
- Rash – Prolia can cause a rash, itching, or dry skin.
- Muscle & bone pain – Prolia can cause bone, muscle, or joint pain
- Low calcium – Prolia can very rarely lower the calcium in the blood. Patients should tell their doctor if they develop:
- Tingling in the hands, feet, or around the mouth
- Muscle cramps or twitching
- Muscle weakness
- Jaw problem – Prolia has very rarely been associated with a jaw problem called osteonecrosis
Prolia should not be taken during pregnancy or breastfeeding. Patients who become pregnant should stop taking this medication and contact their doctor.
People who should NOT take Prolia include:
- Those allergic to Prolia or any ingredient in the medicine
- Pregnant or breast-feeding women
Anyone who becomes pregnant while taking Prolia should notify their doctor immediately.
Patients taking Prolia should call their doctor if they feel sick and want to stop, or if they are concerned about any side effects.
Other reasons to call a doctor while taking Prolia include:
- Tingling in hands, feet or around mouth
- Becoming pregnant or planning pregnancy
- New severe pain in the jaw
- Muscle cramps, pain, or weakness
- Fever or possible infection
Video
Watch Canadian rheumatologist Dr. Andy Thompson introduce Prolia in this short video:
Resources
Drug Identification Number (DIN)
- 02343541 (Injection)