Tysabri - Frequently Asked Questions 2 of 3
Q. Will my insurance cover the cost of Tysabri?
A. According to Biogen Idec Canada, most private insurers are now reimbursing the cost of Tysabri. Generally insurance companies require prior authorization before they will reimburse. This means that the insured person needs to contact his/her insurance company in advance of purchasing the drug to ensure that the cost will be reimbursed.
Q. How is Tysabri taken?
A. Tysabri is given via monthly intravenous infusion at a medical facility.
Q. How long does an infusion take?
A. The actual infusion takes about one hour. After the infusion, you will be observed for another hour to make sure you are not having any reactions that may need medical help. The overall visit will take longer than that because of the risk management discussion and paperwork that will need to be processed at the infusion site.
Q. Are infusions painful?
A. A person getting an intravenous infusion will probably feel a sharp pain or some discomfort when the needle penetrates the skin and vein, but then the discomfort should subside as the infusion proceeds. There may also be discomfort when the infusion needle is removed and the site may or may not feel sore for a day or so.
Q. Should I switch from the therapy I'm taking now?
A. This question can only be answered through discussions between an individual and his or her neurologist. The discussion should focus on how well the individual is doing on his or her current therapy and what is currently understood about the potential risks and benefits of Tysabri.
Q. I have relapsing MS and have never tried any of the disease-modifying therapies. Will I be able to use Tysabri?
A. Health Canada recommends that Tysabri be used in persons who have had inadequate response to other approved MS therapies, or who are unable to tolerate other approved MS therapies. This is a question you should discuss with a neurologist who is knowledgeable about MS and familiar with your condition and personal circumstances.
Q. Can I switch to Tysabri if I'm on another MS drug right now?
A. Possibly. This is a matter that should be discussed with your neurologist. The prescribing information states that Tysabri should not be given to patients whose immune systems are compromised or weakened. There will likely be a period of time between the end of your current therapy and the beginning of Tysabri. The length of time may vary depending on the type of therapy you are currently on and the period necessary to "wash out" the current drug from your system. If a person is currently using an approved MS therapy such as glatiramer acetate or interferon beta and is being switched to Tysabri, the "wash out" period would probably be a few weeks before beginning Tysabri infusions. If a person has recently been prescribed Novantrone, Cytoxan, Imuran, or other strong immune-suppressing drug, the "wash out" period would be longer before beginning Tysabri. This should be discussed with your neurologist.
The Canada-approved prescribing information does not provide specific recommendations for "wash-out" or waiting periods before beginning treatment with Tysabri. However, for the post-marketing study involving persons who had been enrolled in the original phase III studies of Tysabri (AFFIRM and SENTINEL trials), the American FDA recommends that anyone who has been taking an immune-modifying MS drug (such as Copaxone, Betaseron, Avonex, or Rebif) should not begin Tysabri for two weeks after the last dose, and that anyone who has been taking an immune-suppressing drug (such as Novantrone, Cytoxan or Imuran) should not begin Tysabri for three to six months after the last dose.
Q. How effective is Tysabri?
A. In a clinical trial of two years' duration, (the AFFIRM study), 942 individuals received either Tysabri or inactive placebo. The treated group experienced a 42% reduced risk of progression of disability, a 68% reduction of clinical relapses, and an 83% reduction in the development of new or newly enlarging MRI-detected brain lesions. Tysabri also reduced the mean number of enhancing (active) MRI lesions by 92% after the first and second year. These results were described in a published paper (The New England Journal of Medicine 2006;354:899-910 ).
A second two-year trial, (the SENTINEL study) involved 1171 individuals with relapsing MS who were on Avonex and had experienced at least one relapse during the previous 12 months. All participants continued on Avonex, in combination with either Tysabri or inactive placebo given by intravenous infusions every four weeks for up to 116 weeks. After one year, participants who had Tysabri added to Avonex experienced a 54% reduction in the rate of clinical relapses compared to those on placebo and Avonex, which was also maintained at two years with a 55% reduction.
This combination therapy resulted in a 24% decrease in the risk of sustained disability progression. MRI scans showed an 83% reduction in the Tysabri plus Avonex group in enlarging MRI lesions, and an 89% reduction in lesions showing active inflammation. Results of this study were described in a published paper (The New England Journal of Medicine 2006;354:911-923). Two cases of progressive multifocal leukoencephalopathy (PML), one of which was fatal, were diagnosed in those on combination therapy.
Q. What is meant by the statement that Tysabri should not be taken by people who have compromised immune systems or who are taking other immunosuppressive or immunomodulatory agents?
A. This means that Tysabri would not be used in people whose immune systems are weak, such as people who have MS plus leukemia or lymphoma, or who are taking immune-suppressing drugs or other MS drugs such as Avonex, Betaseron, Rebif, or Copaxone. Other drugs sometimes taken by people with MS which may weaken their immune systems include Novantrone, Cytoxan or Imuran, or monthly intravenous steroids.
There is no warning against the use of periodic steroids to treat relapses in people taking Tysabri; however, the chronic use of "pulse" or monthly steroids would possibly weaken the immune system and therefore should probably be avoided wherever possible.
Q. Is Tysabri better than the other available MS therapies?
A. Tysabri has not been compared head-to-head against any other approved MS drug, and that is the only way to truly compare the effectiveness of the MS drugs. However, generally clinicians agree that the immunomodulatory drugs approved for use in MS reduce the rate of relapses by about one-third. By contrast, after two years Tysabri reduced the rate of relapses by about two-thirds as compared to placebo. The investigators also reported that Tysabri reduced the risk of sustained progression of disability over those two years. There is some evidence that other approved MS drugs also slow disease progression.
It is important to note that since MS is such a diverse disease, there is no "one size fits all" treatment strategy. Any decision about whether to take any of the disease-modifying therapies should be made after careful discussion between an individual and his or her physician of its potential risks and benefits.