What is Imvanex and what is it used for?
Imvanex is a vaccine used for immunization against smallpox in adults. It contains a modified live form of the Vaccinia virus called “Vaccinia Ankara.” This virus is related to the smallpox virus but does not cause disease in humans and has been modified so that it cannot replicate (or reproduce) in human cells. The vaccine was officially declared defeated in 1980; the last known case of the disease occurred in 1977. This vaccine will be used in situations where it is considered necessary to provide protection against smallpox, in accordance with official recommendations.
How is Imvanex used - Smallpox vaccine?
Imvanex is available as a suspension for subcutaneous injection, preferably in the shoulder. In people who have not previously been vaccinated against smallpox, two doses of 0.5 ml should be used; the second dose should be administered at least 28 days after the first. If a booster dose is deemed necessary in individuals who have been vaccinated against smallpox in the past, a single dose of 0.5 ml should be given, except in patients with a weakened immune system (the body's natural defenses). who must receive two booster doses, the second of which at least 28 days after the first.The vaccine can only be obtained with a doctor's prescription.
How does Imvanex - Smallpox vaccine work?
Vaccines work by "teaching" the immune system to defend itself against a disease. When a person is given the vaccine, the immune system recognizes the viruses in the vaccine as 'foreign' and makes antibodies against those viruses. When this person is re-exposed to these or similar viruses, the antibodies, along with other components of the immune system, will be able to kill the viruses and protect the body from disease. Imvanex contains a modified form of the Vaccinia virus, which it does not cause disease in humans and cannot replicate in human cells. The antibodies produced against this virus, due to its similarities to the smallpox virus, are also expected to provide protection against smallpox. Vaccines containing Vaccinia viruses have been used effectively in the campaign to eradicate smallpox.
What benefit has Imvanex - Smallpox vaccine shown during the studies?
Over the course of the studies, Imvanex has been shown to be effective in stimulating the production of antibodies to a level that is expected to warrant "immunization against smallpox. Five major studies were conducted involving more than 2,000 adults, including patients with HIV. and atopic dermatitis (an itchy skin manifestation caused by an overactive immune system) and people who had previously been vaccinated against smallpox. Two of the studies looked specifically at the effectiveness of Imvanex as a booster vaccination. Although studies have shown that Imvanex should provide immunization against smallpox, the exact level of protection and duration cannot be determined from the results of the studies.
What is the risk associated with Imvanex - Smallpox Vaccine?
The most common side effects seen with Imvanex (seen in more than 1 in 10 people) are headache, nausea, myalgia (muscle pain), tiredness and reactions at the injection site (pain, redness, swelling, hardening and itching). For the full list of side effects reported with Imvanex, see the package leaflet. Imvanex must not be used in patients who are hypersensitive (allergic) to the active substance or to any of the other trace ingredients, such as chicken protein, benzonase and gentamicin.
Why has Imvanex - Smallpox Vaccine been approved?
The Committee for Medicinal Products for Human Use (CHMP) noted that Imvanex is effective in stimulating the production of antibodies to a level that is expected to provide immunization against smallpox, although the exact level and duration of protection that would be ensured in the course of an "epidemic are not known. As for safety, the Vaccinia virus in Imvanex cannot replicate in human cells and, as a result, is less likely to cause side effects than previous smallpox vaccines. Imvanex would therefore offer benefits to people who cannot be immunized with vaccines containing replicating viruses, such as those with a weakened immune system. Taking all the data into account, the CHMP decided that Imvanex's benefits are greater than its risks and recommended that it be approved for use in the EU. Imvanex has been authorized under 'Exceptional Circumstances' as it has not been possible to obtain complete information on Imvanex due to the non-existence of the disease. Each year the European Medicines Agency will review the new information available and this summary will be updated accordingly.
What information is still awaited for Imvanex - Smallpox Vaccine?
Since Imvanex has been authorized under exceptional circumstances, the company that markets Imvanex will provide further data from studies on the changes in antibody levels seen in vaccinated people. Further data on the benefits and risks of the vaccine will be collected as part of observational studies in vaccinated patients as well as in the event that a smallpox epidemic emerges in the future.
What measures are being taken to ensure the safe and effective use of Imvanex - Smallpox Vaccine?
A risk management plan has been developed to ensure that Imvanex is used as safely as possible. Based on this plan, safety information has been added to the summary of product characteristics and information leaflet for Imvanex, including the appropriate precautions to be followed by healthcare professionals and patients.
Other information about Imvanex - Smallpox vaccine
On 31 July 2013, the European Commission issued a "Marketing Authorization" for Imvanex, valid throughout the European Union. For the full version of the Imvanex EPAR, please consult the Agency's website: ema.Europa.eu / Find medicine / Human medicines / European public assessment reports. This summary was last updated on 07-2013.
The information on Imvanex - Smallpox Vaccine published on this page may be out of date or incomplete. For a correct use of this information, see the Disclaimer and useful information page.
