- This is how rituximab works
- When is Rituximab used?
- This is how rituximab is applied
- What are the side effects of Rituximab?
- What should be considered when using rituximab?
- How to Get Rituximab Drugs
- Since when is Rituximab known?
The active substance rituximab is an antibody against certain cells of the immune system. It is one of the first targeted cancer therapeutics to be used in lymphoma and leukemia. In addition, rituximab is used in autoimmune diseases such as rheumatoid arthritis. Here you can read more about the effects and use of Rituximab, side effects and other interesting facts.
This is how rituximab works
Rituximab is a therapeutic antibody (therapeutic immunoglobulin). Antibodies are proteins that are naturally formed in the body to recognize and neutralize foreign or harmful proteins (such as parasites, bacteria and viruses). In general, an antibody is Y-shaped and has two arms with which it can specifically recognize and bind the surface structures (epitopes) of proteins. Over the other end, he then lures to immune cells, which are to destroy the so marked target structure.
Antibodies are produced by B cells (also called B lymphocytes). It is a type of cell from the group of white blood cells. On contact with an impurity, they form suitable antibodies that attack the invader. After successful defense, some B cells convert to so-called memory cells, which carry the "memory" of the special intruder. Thus, in a later re-attack by the same foreign substance antibody production can be set much faster than the first contact.
Like many cells, B cells have surface proteins to identify themselves with: the protein CD20. This fact is used in the treatment of diseases that are associated with too high a number of B cells in the body, with overactive B cells or unfunctional B cells. These include blood cancer (leukemia), lymphoma and autoimmune diseases such as rheumatoid arthritis.
The specially developed antibody rituximab attaches to the CD20 antigen of B cells, signaling other immune cells to destroy them. Also referred to as "targeted cancer therapy," treatment has far fewer side effects than traditional therapies using drugs that indiscriminately affect all dividing cells (cancer cells and healthy cells).
Recording, removal and Excretion of rituximab
Following infusion or injection into blood vessels (intravenously) or under the skin (subcutaneously), the rituximab antibodies circulate and reach the site where they are to act. The antibodies are degraded only slowly and thus have a rather long duration of action in the body of six days to two months. Then rituximab is broken down by cells of the immune system or in the liver.
When is Rituximab used?
The active substance rituximab is used to treat the following diseases:
- Non-Hodgkin's lymphoma (NHL, cancer of the lymphatic system) - Use in combination with other active ingredients
- Rheumatoid arthritis - Use in combination with the active substance methotrexate
Rituximab is used in several cycles, with weeks to months apart.
This is how rituximab is applied
Rituximab is usually given as an infusion into the bloodstream, administered by a doctor. To determine the dosage, the body surface is estimated by the size and weight of the patient. Per treatment, drug amounts of about 500 to 1000 milligrams of rituximab are administered. The number of cycles and the distance between them are also set by the doctor. Some patients receive the drug weekly, others at intervals of up to three months
In the treatment of cancer with rituximab in addition chemotherapeutic agents are administered. Thus, the disease is treated simultaneously in several ways, of which one promises the greatest possible success in healing.
What are the side effects of Rituximab?
During treatment with rituximab more than ten percent of patients experience side effects such as bacterial and viral infections, reduced white blood cells and platelets, allergic reactions, some with swelling (edema), nausea, itching, rash, hair loss, fever, headache and chills.
Other possible rituximab side effects include fungal infections, sinusitis, anemia, hypersensitivity reactions, high blood sugar, weight loss, elevated cholesterol, decreased calcium levels, sensory disturbances, insomnia, agitation, dizziness, anxiety, dry eyes, earache, cardiac arrhythmia, high or low blood pressure, respiratory disease, Dyspnea, coughing, vomiting, abdominal pain, indigestion, skin disorders, muscle aches and colds. Such side effects occur in one in ten to a hundred people treated.
What should be considered when using rituximab?
There are no known interactions between rituximab and other drugs.
Because rituximab may be detrimental to cardiac function and performance, patients with pre-existing cardiac disease should be monitored very carefully during treatment.
Patients with severe infections (such as tuberculosis, HIV, viral hepatitis) should not be treated with rituximab as it will further weaken the immune system.
Because rituximab remains in the blood for a very long time, can pass through the placenta and enter breast milk, treated women can not conceive or breastfeed for up to one year after treatment. Otherwise, damage to the child is to be expected.
Rituximab should be used in adults 18 years of age and older, as there are no data on safety and efficacy for the treatment of children and adolescents under the age of 18 years.
How to Get Rituximab Drugs
Treatment with Rituximab usually takes place directly in a hospital or specialized clinic, which then also prepares the drug individually for each patient.
Since when is Rituximab known?
The antibody Rituximab was developed by the pharmaceutical company IDEC Pharmaceuticals and approved in the EU in 1998, where it is marketed by the pharmaceutical company Roche. It was the first antibody approved for the treatment of cancer (1997 in the USA). An approval extension was granted in the EU in 2006 for the treatment of rheumatoid arthritis and 2012 for Wegener's disease. The US patent expires in 2015, after which there is a possibility that other pharmaceutical companies will buy generic drugs rituximab launch.