Disease modifying drug therapy What to expect from self-administered drugs
Interferon beta drugs (Avonex, Betaferon, Rebif and Extavia)
Glatiramer acetate (Copaxone)
- What benefits can I expect from these drugs?
- Starting treatment
- Administration and side effects
- Characteristics of the self-administered disease modifying drugs
- Neutralising antibodies
What benefits can I expect from these drugs?
While clinical trials have demonstrated the benefits of these drugs, it is important to remember that just as every individual's experience of MS is unique, each individual's response to the drugs will also be different. In this respect, some people will do better than expected, while others might not do as well.
It is also important to recognise that these drugs are long-term drugs and the benefits they offer will not be seen immediately. As the benefits of the drugs will only be seen over time, stopping and starting them will reduce their effectiveness.
Interferon beta and glatiramer acetate have been used in the UK and the US for over 15 years and have established a very good safety profile. Studies of the effects of these drugs in the treatment of MS have identified two main benefits:
- a reduction in the frequency and severity of relapses; (interferon beta and glatiramer acetate)
- a reduction in the rate of disease progression (interferon beta only)
Results of clinical trials have also indicated that the disease modifying drugs reduce the accumulation of new MS lesions that are detected using magnetic resonance imaging (MRI).
Frequency and severity of relapses
The four interferon beta drugs (Avonex, Betaferon, Rebif and Extavia) and glatiramer acetate (Copaxone) have been shown to reduce the frequency and severity of relapses by around one-third in patients with relapsing remitting MS.
Three of the interferon beta drugs (Betaferon, Rebif and Extavia) have also been shown to reduce the frequency and severity of relapses occurring in secondary progressive MS where relapses are still a feature.
People receiving treatment are likely to experience some relapses. However, most people experience fewer relapses than before they started treatment and their relapses are usually less severe.
Disease progression
Clinical trials have provided evidence that the four interferon beta drugs (Avonex, Betaferon, Rebif and Extavia) delay disease progression but there is a lack of clarity about the extent to which they are able to do so.
Clinical trials for glatiramer acetate (Copaxone) have not yet demonstrated an effect on disease progression. Consequently, the drug is not licensed for this particular outcome.
Starting treatment
The assessment process
There may be a number of stages to the assessment process. It should involve a series of assessments by a prescribing neurologist as well as a series of meetings and discussions with an MS nurse. You will be involved in every stage of the assessment process and should use it as an opportunity to seek answers to any questions about the drugs that remain unanswered.
You should also use this opportunity to discuss any long-term plans you may have. For instance, if you are planning to start a family, you will need to build this in to any plans to start drug treatment. There is limited information on the use of these treatments in pregnancy. For this reason you must not start treatment whilst pregnant. If you become pregnant whilst taking one of the treatments you should contact your neurologist and discontinuation of therapy should be considered.
It is not known whether these treatments are excreted in human milk. Because of the potential harm to breastfed infants, you should consult your neurologist in weighing up the risks associated with breastfeeding whilst on drug treatment.
Men who are planning to start a family also need to discuss this with their neurologist and MS nurse.
The assessment process will offer you an opportunity to discuss any concerns you may have over the practicalities of starting treatment and how it will fit in with your lifestyle. For instance, you might work full-time or have to travel frequently and will want to consider how you can fit these drugs into your routine.
Checking for other conditions
Blood tests will be performed before you start treatment to check for any other problems that might affect how well you do on the drugs. Before starting on these drugs, you should tell the neurologist if you have any pre-existing conditions or have experienced any reactions to previous drugs or treatments. If you do, you may still be able to receive the drugs but may need to start them in a different way.
Blood tests during treatment
If the neurologist prescribes one of the interferon beta drugs, blood tests may be performed throughout the time you are receiving treatment, to check that your body is tolerating it well. Your blood will be checked on a regular basis during the first year of treatment and assuming you are tolerating the treatment the tests may be reduced to a frequency of every six months, though this may vary between centres.
Should you be prescribed glatiramer acetate you will not be required to have regular blood tests.
Administration and side effects
How are these drugs given?
All of the licensed self-administered drugs are given by injection either under the skin or into the muscle (see table below for administration characteristics of each individual drug).
As shown in the table, many of these drugs need to be stored in the fridge. All drugs will need to be at room temperature before they are injected as cold temperatures can make them painful to inject. It is therefore important to follow the storage and administration directions carefully.
People who are anxious about injecting often choose to use autoinjectors. These are available for all the self-administered drugs and work like a pen which holds a needle and syringe inside. Most types of autoinjector allow you to inject without having to see the needle going in.
Side effects
More often than not, the side effects of these drugs are mild and manageable (see table across pages 16 and 17 for more information about side effects). It is often the case that the side effects experienced when on these drugs are worse at the start of treatment and reduce over time as your body gets used to them.
There are various strategies that your MS nurse may recommend in order to reduce the risk of experiencing side effects whilst on these drugs. For instance, if you are prescribed one of the interferon beta drugs, your MS nurse may recommend that you start on a lower dose of the drug and slowly increase the dosage over time to allow your body to adjust to the drug, or where flu-like symptoms after injecting persist, your nurse may recommend that you change the time of day of injection so that you sleep through the worst of your side effects.
It is important to keep your health professionals informed of any new, unusual or persistent symptoms you experience.
| Interferon beta 1a | Interferon beta 1a | Interferon beta 1b | Interferon beta 1b | Glatiramer acetate | |
|---|---|---|---|---|---|
| Product name | Avonex | Rebif | Betaferon | Extavia | Copaxone |
| Manufacturer | Biogen Idec | Merck Serono | Bayer Schering | Novartis | Teva Pharmaceuticals |
| How often is it given? | Once a week | Three times a week | Alternate days | Alternate days | Every day |
| How is it injected? | Into the muscle | Under the skin | Under the skin | Under the skin | Under the skin |
| Does the drug come premixed? | Two versions are available: a premixed version (PFS) which comes ready to inject, and a version which must be mixed before use (BIO-SET) | Yes | No | No | Yes |
| Storage | Premixed version: fridge 2-8°C but a single vial can be kept at room temperature for up to a week*. The BIO-SET version can be kept at room temperature for up to 2 years | In the fridge between2-8°C* | At room temp 25°C or less | At room temp 25°C or less | In the fridge between 2-8°C or at room temp (15-25°C) for up to 1 month* |
| Regular blood tests? | Yes | Yes | Yes | Yes | No |
| Common side effects | Flu like symptoms after injecting | Flu like symptoms after injecting, site reactions | Flu like symptoms after injecting, site reactions | Flu like symptoms after injecting, site reactions | Injection site reactions and lipoatrophy (indentations in the skin) |
| Less common side effects | Changes in menstruation/ periods, blood abnormalities, neurological symptoms, mood changes | Changes in menstruation/ periods, blood abnormalities, neurological symptoms, mood changes | Changes in menstruation/ periods, blood abnormalities, neurological symptoms, mood changes | Changes in menstruation/ periods, blood abnormalities, neurological symptoms, mood changes | Post injection reaction may present in the form of chest tightness, breathlessness, anxiety, flushing and palpitations. These symptoms typically pass after a few minutes |
This information is based on the current product information, but may be subject to change. Always refer to the product information leaflet enclosed with the drugs for the most up-to-date information.
All drugs will need to be at room temperature before they are injected as cold temperatures can make them painful to inject. Refer to your health professional for directions on injecting refrigerated products.
Neutralising antibodies
Antibodies are proteins produced by the immune system to fight foreign substances such as infections. As with drugs that are used in some other conditions such as diabetes, use of interferon beta over a long period of time may result in the production of what are known as 'neutralising antibodies'. These antibodies may reduce the effectiveness of the drug. Over the long-term this may mean that people taking interferon beta receive less benefit from it and start to experience a similar number of relapses as they would have done without taking the drug.
Neutralising antibodies are not associated with any new side effects or long-term safety issues. Most people will not develop neutralising antibodies and in some people the neutralising antibodies will disappear again over time.
The presence of neutralising antibodies alone is not a reason to stop or change drugs.
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