IVIG for MS

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IVIG use

IVIG is given as a plasma protein replacement therapy (IgG) for immune deficient patients who have decreased or abolished antibody production capabilities. In these immune deficient patients, IVIG is administered to maintain adequate antibody levels to prevent infections and confers a passive immunity. Treatment is given every 3–4 weeks. In the case of patients with autoimmune disease, IVIG is administered at a high dose (generally 1-2 grams IVIG per kg body weight) to attempt to decrease the severity of the autoimmune diseases such as Dermatomyositis.

IVIG is useful in some acute infection cases such as in Kawasaki's Disease and pediatric HIV infection and Guillain–Barré syndrome.

Mechanism of action

The precise mechanism by which IVIG suppresses harmful inflammation has not been definitively established but is believed to involve the inhibitory Fc receptor. The actual primary target(s) of IVIG in autoimmune disease are still unclear, however. IVIG may work via a multi-step model where the injected IVIG first forms a type of immune complex in the patient. Once these immune complexes are formed, they interact with activating Fc receptors on dendritic cells[5] which then mediate anti-inflammatory effects helping to reduce the severity of the autoimmune disease or inflammatory state.

Additionally, the donor antibody may bind directly with the abnormal host antibody, stimulating its removal. Alternatively, the massive quantity of antibody may stimulate the host's complement system, leading to enhanced removal of all antibodies, including the harmful ones. IVIG also blocks the antibody receptors on immune cells (macrophages), leading to decreased damage by these cells, or regulation of macrophage phagocytosis.

IVIG may also regulate the immune response by reacting with a number of membrane receptors on T cells, B cells, and monocytes that are pertinent to autoreactivity and induction of tolerance to self.

A recent report stated that IVIG application to activated T cells leads to their decreased ability to engage microglia. As a result of IVIG treatment of T cells, the findings showed reduced levels of tumor necrosis factor-alpha and interleukin-10 in T cell-microglia co-culture. The results add to the understanding of how IVIG may affect inflammation of the central nervous system in autoimmune inflammatory diseases.

IVIG notes

IVIG is an infusion of IgG antibodies only. Therefore, peripheral tissues that are defended mainly by IgA antibodies, such as the eyes, lungs, gut and urinary tract are not fully protected by the IVIG treatment.

XLA patients are immune to the most virulent adverse effect, anaphylactic shock, as they do not have the antibodies to react against the treatment. Anaphylactic shock has a higher chance to occur in IgA deficient patients which do have other antibody types.

In case of recurring side effects, it is recommended to slow the pace of the IVIG administration and to reduce the dosage. It is also advisable to change IVIG brand, as some people react against a specific brand.

If the patient is diabetic, he should take into consideration the medium in which the antibodies are solubilized in the IVIG treatment, as some brand solubilize antibodies with high concentrated sugars (such as sucrose and maltose).

U.S. Food and Drug Administration (FDA) guidelines for IVIG state the product should be:

Prepared out of at least 1,000 different human donors.

All four IgG subgroups (1-4) should be present.

The IgG should maintain biological activity and lifetime of at least 21 days.

Does not contain samples which are HIV, hepatitis B, hepatitis C positive.

Screened and treated in a manner that destroys viruses.

IVIG is also considered a modulator of the immune system and was shown to be beneficial in treating numerous autoimmune diseases such as relapsing and remitting multiple sclerosis (MS), myasthenia gravis, pemphigus, polymyositis (PM), dermatomyositis (DM), Wegener's

granulomatosis (WG), Churg-Strauss syndrome, chronic inflammatory demyelinating polyneuropathy (CIDP) and more.

IVIG can be given to pregnant women.

IVIG is also used as a treatment for unexplained recurring miscarriages. The effectiveness of the therapy is controversial.

IVIG cost is climbing and well over $50/g. ($10,000 for a 100 kg (220 lbs) person at 2g/kg)

IVIG dose

Dosage of IVIG is dependent on indication.

For primary immune dysfunction 100 to 400 mg/kg of body weight every 3 to 4 weeks is implemented.

For neurological and autoimmune diseases 2 grams per kilogram of body weight is implemented for three to six months over a five day course once a month. Then maintenance therapy of 100 to 400 mg/kg of body weight every 3 to 4 weeks follows.

Allogeneic bone marrow transplant

Chronic lymphocytic leukemia

Idiopathic thrombocytopenic purpura

Pediatric HIV

Primary immunodeficiencies

Kawasaki disease

Chronic inflammatory demyelinating polyneuropathy (CIDP). Only the "Gamunex" brand manufactured by Talecris is approved for CIDP (in 2008), under the U.S. Orphan Drug law provisions

Kidney transplant with a high antibody recipient or with an ABO incompatible donor

In 2004 the FDA approved the Cedars-Sinai IVIG Protocol which has been 90-95% successful in removing antibodies from the blood of kidney transplant recipients so that they can accept a living donor kidney from any healthy donor no matter blood type (ABO incompatible) or tissue match.

[edit] In Phase III testing in the US (as of December 2008)

Alzheimer's Disease