IVIG seems to work in neurological diseases by increasing the action of some parts of the immune system and decreasing the action of others. No one exactly knows all of the mechanisms of action in multiple sclerosis (how it works), but scientists are honing in on which components of the immune system are effected by IVIG and the role they play in multiple sclerosis.
What Is it For?
IVIG is used in MS to slow progression of the disease, reduce number of and limit disability and MS symptoms.
IVIG is used "off-label" in MS, meaning it has not been approved for this use by the FDA (many drugs are used off-label in MS, as discussed in this article: What is "off-label" use of drugs and is it legal?).
Specific Uses in MS
As a general disease-modifying therapy for relapsing-remitting MS, it just seems like the evidence isn't there to jump at the chance to take IVIG. However, it does show promise in a couple of specific areas:
Post-Partum Women: IVIG has been shown to be effective in preventing relapses in the period following childbirth, which occurs in about one-third of women.
Cannot Tolerate DMTs: It is recommended that IVIG be used as a second-line therapy in people with RRMS who cannot tolerate the current disease-modifying therapies, namely Copaxone, Betaseron, Avonex and Rebif.
Pregnant Women: Some data and reports suggest that giving a patient IVIG throughout pregnancy may help reduce the chance of relapse during pregnancy, although the risk of relapse during pregnancy is greatly reduced anyway.
Clinically Isolated Syndrome: One small study showed that people given IVIG during a clinically isolated syndrome were only about half as likely to convert to clinically definite MS within a year.
Secondary-Progressive MS: There has been at least one European study that showed that IVIG does help slow disease progression in people with primary progressive MS, measured by EDSS scores. However, other endpoints did not show any effect. No significant improvement or effect was demonstrated in people with secondary progressive MS in this study.
NOT During a Relapse: IVIG has not been shown to have any benefit when administered during a relapse when the person is already getting treated with Solu-Medrol.
How Effective Is It?
At this time, no one really knows the answer to this question for multiple sclerosis. IVIG has been proven effective in the treatment of other neurological diseases, such as Guillain-Barré syndrome and myasthenia gravis.
There have been several studies that have shown that IVIG has positive effects on MS, while others demonstrate no effect whatever in MS. Most of the trials have been small and not rigorous enough to "prove" anything one way or another in terms of effectiveness.
One Australian study did show a small, but statistically significant improvement in disability, as measured by the expanded disability status scale (EDSS). Others have shown small effects on improving MRI (reducing size or number of lesions). However, many others have shown no difference whatsoever between IVIG and placebo as a disease-modifying approach for relapsing-remitting MS. Several positive studies have shown that IVIG administered right after childbirth does have a statistically significant effect on reducing relapses in new mothers.
Usual Dosage/How Taken
Dosages and frequency of doses have not been established for MS, but some recommend that 1 gram of IVIG per kilogram of body weight be given monthly. Some doctors also give a course of 400 mg/kg/day for 5 days.
Side Effects of IVIG
The most common side effect of IVIG is headache, which is usually responsive to over-the-counter painkillers, such as Tylenol. Other side effects include: fever, joint pain, chest pain and vomiting. Some people get a rash after receiving IVIG.
Some serious, but rare side effects of IVIG have been noted. These include: aseptic meningitis (inflammation of the layers of tissue surrounding the brain with no infectious cause), thrombotic events (heart attacks, strokes, pulmonary embolism, deep vein thrombosis) and kidney dysfunction or failure.
Potential Interactions and Warnings
IVIG should NOT be used in people with the following conditions:
- IgA deficiency
- Kidney problems/failure
- Heart problems
- Sensitivity to immune globulins
- Sensitivity to maltose or sucrose (these ingredients may be in some IVIG preparations)
The only clearly defined potential drug interaction with IVIG is with live virus vaccines, as the antibodies can render the vaccines ineffective.
IVIG has become extremely expensive, at an estimated $100 per gram. At a typical dosage of 1g/kg body weight, a 154-pound (70 kg) person would therefore need 70 grams of IVIG, costing $7000 for each monthly infusion for the drug alone (without associated facility or nursing costs).