Disease-modifying drugs (DMDs): what’s the difference?

Immunomodulators

	Rebif® (interferon beta-1a) (1)	Avonex® (interferon beta-1a) (2)	Betaseron® (interferon beta-1b) (3)	Copaxone® (glatiramer acetate) (4)
What is it made of?	Interferon beta-1a is a protein that exists naturally in the body. Interferon beta-1a medications are produced in mammalian cells.		Interferon beta-1b is a slightly modified form of interferon beta that is produced in bacterial cells.	Glatiramer acetate is a synthetic compound which does not occur naturally in the body. It contains four naturally occurring amino acids (smallest units of protein) lined up in random order.
How does it work?	The precise mechanism of action is still unknown. It is thought interferon beta works to decrease the number of harmful immune cells outside the CNS that cause inflammation. As well, interferon-beta “strengthens the blood-brain barrier”, which helps prevent immune cells from entering the CNS and causing damage. (1),(2)			The precise mechanism of action is still unknown. It is thought that glatiramer acetate works outside and inside the central nervous system (CNS) to change the way the immune system reacts.
When was it approved by Health Canada?	February 5, 1998	April 6, 1998	July 19, 1995	September 4, 1997
Efficacy in RRMS
Slows the progression of disability
Reduces the number of relapses
Reduces the number of hospitalizations
Reduces the need for steroids
Reduces disease activity as measured by MRI*
Administration
Route of administration	Just under the skin (subcutaneous injection)	Into the muscle (intramuscular injection)	Just under the skin (subcutaneous injection)	Just under the skin (subcutaneous injection)
Frequency of injections	3 times/week	1 time/week	Every other day (3–4 times/week)	Daily (7 times/week)
Needle gauge (G) (the higher the gauge, the thinner the needle)	29G or 30G	23G (25G needle can be substituted)	30G	29G
Needle length	½ inch	1-¼ inch	½ inch	½ inch
Autoinjector available	Yes	Yes	Yes	Yes
Pre-mixed medication	Yes	Yes	No	Yes
Safety/Tolerance
Most common side effects	Flu-like symptoms (fatigue, chills, fever, muscle aches, and sweating) and injection site reactions (swelling, redness, discoloration, and pain). Most of these symptoms tend to disappear over time.	Flu-like symptoms (fatigue, chills, fever, muscle aches, and sweating). Most of these symptoms will tend to disappear after the initial few weeks of treatment.	Flu-like symptoms (fatigue, chills, fever, muscle aches, and sweating) and injection site reactions (swelling, redness, discoloration, and pain). Most of these symptoms tend to disappear over time.	Side effects that generally resolve on their own and do not require medical attention unless they continue for several weeks or are bothersome: injection-site reactions (e.g., swelling, the development of a hardened lump, redness, tenderness, increased warmth of the skin, itching at the site of the injection); runny nose; tremor†; unusual tiredness or weakness†; weight gain. †Since it may be difficult to distinguish between certain common symptoms of MS and some side effects of glatiramer acetate, be sure to consult your health care professional if an abrupt change of this type occurs.

*The exact relationship between MRI findings and the clinical status of patients is unknown.
Rebif® is a registered trademark of EMD Serono Canada Inc.
Avonex® is a registered trademark of Biogen Idec Canada Inc.
Betaseron® is a registered trademark of Bayer Inc.
Copaxone® is a registered trademark of Teva Pharmaceuticals Industries Ltd.

Selective Adhesion Molecule (SAM) Inhibitors

Natalizumab is generally recommended for MS patients who have had an inadequate response to, or are unable to tolerate, other MS therapies.

	Tysabri® (natalizumab) (5)
What is it made of?	Natalizumab is a monoclonal antibody that does not occur naturally in the body. It is produced in a mouse cell line.
How does it work?	The precise mechanism of action is still not known. Natalizumab is an immunosuppressant that may act to prevent harmful immune cells from crossing the blood-brain barrier.
When was it approved by Health Canada?	September 28, 2006
Efficacy in RRMS
Slows the progression of disability
Reduces the number of relapses
Reduces the number of hospitalizations
Reduces the need for steroids
Reduces disease activity as measured by MRI*
Administration
Route of administration	Intravenous (IV) infusion by a healthcare professional
Frequency of injections	Every 4 weeks
Pre-mixed medication	No Must be administered by a healthcare professional at a certified infusion clinic. Medication is infused over 1 hour and individual must be observed for 1 hour after the infusion is complete.
Safety/Tolerance
Most common side effects	The most common side effects are infusion-related reactions, including headache, dizziness, fatigue, itchiness and hives. Other possible side effects are urinary tract infections, pneumonia and hypersensitivity reactions such as anaphylaxis.

*The exact relationship between MRI findings and the clinical status of patients is unknown.

Tysabri® is a registered trademark of Biogen Idec and Elan.

At no time should the information presented replace or supersede the recommendations of your own physician. If you have any concerns, please take the information or questions to your physician.

References:
1. Rebif® Product Monograph. EMD Serono Canada Inc. June 2009. (A)
2. Avonex® Product Monograph. Biogen Idec Canada Inc. May 2009. (B)
3. Betaseron® Product Monograph. Bayer Canada Inc. November 2008.  (C)
4. Copaxone® Product Monograph. Teva Neuroscience. April 2009. (D)
5. Tysabri® Product Monograph. Biogen Idec Canada Inc. January 2009. (E)