What is IntronA?
IntronA is a medicine containing the active substance interferon alfa-2b. It is available as a powder and solvent for solution for injection or infusion, as a ready-to-use solution and as a multidose injection pen. All these formulations contain a quantity between 1 and 50 million IU (international units) per milliliter.
What is IntronA used for?
IntronA is indicated in the treatment of:
• hepatitis B (an infection of the liver caused by the hepatitis B virus) of chronic type (protracted over time) in adult patients;
• hepatitis C (infection of the liver caused by the hepatitis C virus) of chronic type (protracted over time). In adults, IntronA can be used on its own (monotherapy), but the optimal use of IntronA in this indication is in combination with ribavirin (an antiviral drug);
in children it is used in combination with ribavirin;
• hairy cell leukemia (cancer of white blood cells);
• chronic myeloid leukemia (CML, another form of white blood cell cancer) in adults. IntronA can be given in combination with cytarabine (an anticancer medicine) in the first 12 months;
• multiple myeloma (a tumor of the spinal cord). IntronA is used to maintain antitumor effects in patients who have responded to previous treatment with anticancer drugs;
• follicular lymphoma (lymphatic tissue tumor). IntronA is given as an adjunctive therapy to anticancer treatments;
• carcinoid tumor (a tumor that affects the endocrine system responsible for hormone production);
• malignant melanoma (a type of skin cancer that attacks cells called melanocytes). IntronA is used after surgery in patients whose melanoma may reappear.
The medicine can only be obtained with a prescription.
How is IntronA used?
Treatment with IntronA should be started by a doctor experienced in treating the condition for which the medicine was prescribed. IntronA is usually given three times a week (every other day), but the injection may be more frequent in some diseases (CML and melanoma). Generally the medicine is administered subcutaneously (under the skin); in melanoma patients it can be given by intravenous infusion (drip into a vein). The dose and duration of treatment depend on the disease treated and the patient's response; dosages range from 2 to 20 million IU per square meter of body surface. For more information, see the package leaflet.
IntronA should be stored in a refrigerator (2 ° C-8 ° C).
How does IntronA work?
The active substance in IntronA, interferon alfa-2b, belongs to the group of "interferons".
Interferons are natural substances produced by the body to help it cope with attacks such as viral infections.
The mechanism of action of alpha interferons in tumors and viral diseases is not yet fully known; however, it is believed that they act as immunomodulators (substances that modify the immune responses, that is to say defense, of the organism). Alpha interferons can also stop the proliferation of viruses.
The interferon alfa-2b contained in IntronA is produced by a method known as "recombinant DNA technique": that is, it is obtained from a bacterium in which a gene (DNA) has been inserted that makes it capable of producing interferon. The replacement interferon alfa-2b acts like naturally produced interferon alpha.
What studies have been carried out on IntronA?
Since interferon alfa-2b has already been used previously for the treatment of a number of diseases in the European Union (EU), the company that makes IntronA has provided data from the scientific literature and from studies on its use with cytarabine in CML (745 patients) and its use in children with chronic hepatitis B. The company also presented information from a series of studies in which IntronA was used on its own or with ribavirin in the treatment of chronic hepatitis C. These studies have involved, overall, 2 552 treatment-naïve patients (i.e. never treated previously) and a total of 345 patients in the disease has relapsed (has recurred) after previous treatment with interferon. The use of IntronA in combination with ribavirin was finally studied in 118 treatment-naïve hepatitis C children and adolescents aged 3 to 16 years.
The main efficacy parameters were response rates in hepatitis studies and survival time in cancer studies.
What benefit has IntronA shown during the studies?
Studies have shown that IntronA is effective in the diseases for which it is indicated. In CML, the number of patients receiving IntronA in combination with cytarabine surviving after 3 years was greater than the number of patients treated with IntronA alone. IntronA has also been shown to produce benefits in children with chronic hepatitis B. IntronA, in combination or not with ribavirin, was effective in the treatment of hepatitis C in adult patients, whether they were treatment-naïve or relapsed. Finally, IntronA has been shown to be effective in children in combination with ribavirin: a response to treatment was observed at a 6-month follow-up visit after 46 years of therapy in one year of children.
What is the risk associated with IntronA?
Side effects with IntronA (generally seen in more than 1 patient in 10) are viral infections, pharyngitis (sore throat), anorexia (loss of appetite), depression, insomnia, anxiety, emotional lability (mood changes), headache, decreased concentration, dizziness, cough, dyspnea (difficulty breathing), nausea, diarrhea, abdominal pain, alopecia (hair loss), itching, dry skin, skin rash, myalgia (muscle pain), arthralgia (joint pain), musculoskeletal pain (muscle and bone pain), injection site reactions, including inflammation, fatigue, tremors, fever, flu-like symptoms, asthenia (weakness), irritability and weight loss. the full list of side effects reported with IntronA can be found in the package leaflet.
IntronA should not be used in people who may be hypersensitive (allergic) to interferon alfa-2b or other ingredients in the medicine. IntronA should not be administered to:
- patients with severe heart disease;
- patients with severe renal or hepatic dysfunction, including that caused by cancer;
- patients with epilepsy or other problems affecting the central nervous system;
- Patients suffering from thyroid disease, if not controlled;
- patients with hepatitis Associated with liver cirrhosis or patients recently treated with immunosuppressive drugs;
- Patients with immune system disorders or organ transplants and taking immunosuppressive drugs;
- children and adolescents with a history of severe mental illness, especially severe depression, suicidal thoughts or suicide attempts.
For the full list of usage restrictions, see the package leaflet.
Why has IntronA been approved?
The Committee for Medicinal Products for Human Use (CHMP) decided that the benefits of IntronA outweigh its risks in the treatment of chronic hepatitis type B and C, hairy cell leukemia, CML, multiple myeloma, follicular lymphoma, carcinoid tumor and malignant melanoma. The Committee therefore recommended that the product be granted marketing authorization.
More information on IntronA
On 9 March 2000, the European Commission issued a marketing authorization valid for the entire European Union to IntronA to SP Europe. The marketing authorization was renewed on 9 March 2005.
For the full EPAR version of IntronA, click here.
Last update of this summary: 06-2007.
