David
Co-Founder
This thread is dedicated to the discussion of Tysabri (Natalizumab) and updates of your personal experience from the prescription process onwards. If this thread becomes popular enough, we're happy to create a subforum dedicated to Tysabri.
About Tysabri
Tysabri (Natalizumab) is used in the treatment of multiple sclerosis and Crohn's disease and was previously named Antegren. Natalizumab is administered by intravenous infusion every 28 days. The drug is believed to work by reducing the ability of inflammatory immune cells to attach to and pass through the cell layers lining the intestines and blood-brain barrier. Natalizumab has proven effective in treating the symptoms of both diseases, preventing relapse, vision loss, cognitive decline and significantly improving quality of life in people with multiple sclerosis, as well as increasing rates of remission and preventing relapse in Crohn's disease.
Several randomized controlled trials have demonstrated that natalizumab is effective in increasing rates of remission and maintaining symptom-free status in patients with Crohn's disease. Natalizumab may be appropriate in patients who do not respond to medications that block tumor necrosis factor-alpha such as infliximab, with some evidence to support combination treatment of Crohn's disease with natalizumab and infliximab may be helpful in inducing remission. Treatment of adolescent patients with natalizumab demonstrates an effectiveness similar to that of adult patients.
In January 2008, the FDA approved natalizumab for both induction of remission and maintenance of remission for moderate to severe Crohn's disease,[26] though it has not been approved for this use in the European Union due to concerns over its risk/benefit ratio.
How Tysabri Works
The interaction of the α4β7 integrin and the addressin (also known as MADCAM1) endothelial cell receptor is believed to contribute to the chronic bowel inflammation that causes Crohn's disease. Addressin is primarily expressed in the endothelium of venules in the small intestine and are critical in guiding T-lymphocytes to lymphatic tissues in Peyer's patches. In CD patients, sites of active inflammation of the bowel in CD patients have increased expression of addressin, suggesting a connection between the inflammation and the receptor. Natalizumab may block interaction between the α4β7 integrin and addressin at sites of inflammation. Animal models have found higher levels of VCAM-1 expression in mice with irritable bowel syndrome and the VCAM-1 gene may also play a part in CD but its role is not yet clear.
Drug Interactions
Natalizumab appears to interact with other immune-modulating drugs to increase the risk of progressive multifocal leukoencephalopathy (PML), an often-fatal opportunistic infection caused by the JC virus. In 2005, two people taking natalizumab in combination with interferon beta-1a developed PML. One died, and the other recovered with disabling sequelae. A third fatal case initially attributed to an astrocytoma was reported in a patient being treated for Crohn's disease. Though the patient was being treated with natalizumab in combination with azathioprine, corticosteroids and infliximab, indications of PML infection appeared only after natalizumab monotherapy was re-introduced. No deaths have been linked to natalizumab when it was not combined with other immune-modulating drugs and other rates of opportunistic infections are not increased in patients taking natalizumab possibly due to the drug’s mechanism of action. Other than a prior history of PML, there is no known method to identify patients at risk of developing PML. Natalizumab's label indicates that it is contraindicated for immunosuppressed individuals or those with a history of PML. Due to the uncertain risk of PML, natalizumab is only available through a restricted distribution program. As of June 2009, ten cases of PML associated with natalizumab have been reported. At least one of them had not previously taken any other inmunomodulator therapy. By Jaunary 21st, 2010 the United States Food and Drug Administration reported a total of 31 confirmed cases of PML associated with natalizumab.
Though the small number of cases precludes conclusion on the ability of natalizumab alone to induce PML, its black box warning states that the drug has only been linked to PML when combined with other immune-modulating drugs and natalizumab is contraindicated for use with other immunomodulators. Corticosteroids may produce immunosuppression, and the Tysabri prescribing information recommends that people taking corticosteroids for the treatment of Crohn's disease have their doses reduced before starting natalizumab treatment. The risk of developing PML was later estimated to be 1 in 1,000 (0.1%) over 18 months though the longer term risks of PML are unknown.
Possible Tysabri Side Effects
Headache, extreme tiredness, joint pain or swelling, pain in arms or legs, swelling of the arms, hands, feet, ankles, or lower legs, muscle cramps, stomach pain, diarrhea, heartburn, constipation, gas, weight gain or loss, depression, night sweats, painful, irregular, or missed menstruation (period), swelling, redness, burning, or itching of the vagina, white vaginal discharge, frequent or painful urination, sudden need to urinate right away, difficulty controlling urination, tooth pain, cold sores
Some side effects of Tysabri can be serious. If you experience any of the following symptoms, it is suggested that you call your doctor immediately:
Sore throat, fever, cough or other signs of infection, rash, hives, itching, difficulty breathing, chest pain, dizziness, chills, flushing, yellowing of the skin or eyes, nausea, vomiting, unusual darkening of the urine
Official Site:
Tysabri.com
Sources
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000289/
http://en.wikipedia.org/wiki/Natalizumab
If you have additional information or corrects for this OP, please PM me with anything you would like added or amended. Thank you!
About Tysabri
Tysabri (Natalizumab) is used in the treatment of multiple sclerosis and Crohn's disease and was previously named Antegren. Natalizumab is administered by intravenous infusion every 28 days. The drug is believed to work by reducing the ability of inflammatory immune cells to attach to and pass through the cell layers lining the intestines and blood-brain barrier. Natalizumab has proven effective in treating the symptoms of both diseases, preventing relapse, vision loss, cognitive decline and significantly improving quality of life in people with multiple sclerosis, as well as increasing rates of remission and preventing relapse in Crohn's disease.
Several randomized controlled trials have demonstrated that natalizumab is effective in increasing rates of remission and maintaining symptom-free status in patients with Crohn's disease. Natalizumab may be appropriate in patients who do not respond to medications that block tumor necrosis factor-alpha such as infliximab, with some evidence to support combination treatment of Crohn's disease with natalizumab and infliximab may be helpful in inducing remission. Treatment of adolescent patients with natalizumab demonstrates an effectiveness similar to that of adult patients.
In January 2008, the FDA approved natalizumab for both induction of remission and maintenance of remission for moderate to severe Crohn's disease,[26] though it has not been approved for this use in the European Union due to concerns over its risk/benefit ratio.
How Tysabri Works
The interaction of the α4β7 integrin and the addressin (also known as MADCAM1) endothelial cell receptor is believed to contribute to the chronic bowel inflammation that causes Crohn's disease. Addressin is primarily expressed in the endothelium of venules in the small intestine and are critical in guiding T-lymphocytes to lymphatic tissues in Peyer's patches. In CD patients, sites of active inflammation of the bowel in CD patients have increased expression of addressin, suggesting a connection between the inflammation and the receptor. Natalizumab may block interaction between the α4β7 integrin and addressin at sites of inflammation. Animal models have found higher levels of VCAM-1 expression in mice with irritable bowel syndrome and the VCAM-1 gene may also play a part in CD but its role is not yet clear.
Drug Interactions
Natalizumab appears to interact with other immune-modulating drugs to increase the risk of progressive multifocal leukoencephalopathy (PML), an often-fatal opportunistic infection caused by the JC virus. In 2005, two people taking natalizumab in combination with interferon beta-1a developed PML. One died, and the other recovered with disabling sequelae. A third fatal case initially attributed to an astrocytoma was reported in a patient being treated for Crohn's disease. Though the patient was being treated with natalizumab in combination with azathioprine, corticosteroids and infliximab, indications of PML infection appeared only after natalizumab monotherapy was re-introduced. No deaths have been linked to natalizumab when it was not combined with other immune-modulating drugs and other rates of opportunistic infections are not increased in patients taking natalizumab possibly due to the drug’s mechanism of action. Other than a prior history of PML, there is no known method to identify patients at risk of developing PML. Natalizumab's label indicates that it is contraindicated for immunosuppressed individuals or those with a history of PML. Due to the uncertain risk of PML, natalizumab is only available through a restricted distribution program. As of June 2009, ten cases of PML associated with natalizumab have been reported. At least one of them had not previously taken any other inmunomodulator therapy. By Jaunary 21st, 2010 the United States Food and Drug Administration reported a total of 31 confirmed cases of PML associated with natalizumab.
Though the small number of cases precludes conclusion on the ability of natalizumab alone to induce PML, its black box warning states that the drug has only been linked to PML when combined with other immune-modulating drugs and natalizumab is contraindicated for use with other immunomodulators. Corticosteroids may produce immunosuppression, and the Tysabri prescribing information recommends that people taking corticosteroids for the treatment of Crohn's disease have their doses reduced before starting natalizumab treatment. The risk of developing PML was later estimated to be 1 in 1,000 (0.1%) over 18 months though the longer term risks of PML are unknown.
Possible Tysabri Side Effects
Headache, extreme tiredness, joint pain or swelling, pain in arms or legs, swelling of the arms, hands, feet, ankles, or lower legs, muscle cramps, stomach pain, diarrhea, heartburn, constipation, gas, weight gain or loss, depression, night sweats, painful, irregular, or missed menstruation (period), swelling, redness, burning, or itching of the vagina, white vaginal discharge, frequent or painful urination, sudden need to urinate right away, difficulty controlling urination, tooth pain, cold sores
Some side effects of Tysabri can be serious. If you experience any of the following symptoms, it is suggested that you call your doctor immediately:
Sore throat, fever, cough or other signs of infection, rash, hives, itching, difficulty breathing, chest pain, dizziness, chills, flushing, yellowing of the skin or eyes, nausea, vomiting, unusual darkening of the urine
Official Site:
Tysabri.com
Sources
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0000289/
http://en.wikipedia.org/wiki/Natalizumab
If you have additional information or corrects for this OP, please PM me with anything you would like added or amended. Thank you!
