Aflunov

The vaccine is given by injection into the shoulder muscle in two single doses, at least three weeks apart. In the event of an officially declared pandemic caused by the H5N1 strain of the influenza A, people who have already been vaccinated with Aflunov (with one or two doses) may be given only one more dose, instead of the two doses recommended for unvaccinated people.

Aflunov can only be obtained with a prescription and should be used according to official recommendations.

Aflunov is a type of vaccine to be given before or during a flu pandemic to protect against a new strain of flu. A flu pandemic happens when a new strain of flu virus appears that can spread easily from person to person because people do not have immunity (protection) against it. Health experts are concerned that a future flu pandemic could be caused by the H5N1 strain of the virus, an infection that can spread from birds to humans (a ‘zoonotic’ infection). 

Vaccines work by preparing the immune system (the body’s natural defences) to defend itself against a specific disease. This vaccine contains some parts of the H5N1 virus. The virus has first been inactivated so that it does not cause any disease. When a person is given the vaccine, the immune system recognises the virus parts in the vaccine as ‘foreign’ and makes antibodies against them. When the person comes into contact with the virus, these antibodies, together with other components of the immune system, will be able to kill the virus and help protect against the disease.

The vaccine contains an ‘adjuvant’ (a compound containing oil) to enhance the immune response.

Aflunov has been shown to produce sufficient antibodies  to stimulate an immune response and protect against H5N1.

At the time of the initial marketing authorisation, two main studies using a strain called A/Vietnam/1194/2004 (H5N1)-like strain (NIBRG-14) provided data on vaccination with Aflunov in healthy adults aged below and above 60 years. In one study involving 3,372 people, subjects were given either a seasonal flu vaccine followed by two doses of Aflunov three weeks apart, or placebo (a dummy vaccine) followed by two doses of an adjuvanted seasonal vaccine three weeks apart. In the first study, 21 days after the second injection, around 90% of people aged below 60 years and around 80% of those aged above 60 years had levels of antibodies that would protect them against H5N1.

In the second study involving 240 people, subjects were given Aflunov using different vaccination schedules. The studies looked at the ability of the vaccine to trigger the production of antibodies (‘immunogenicity’) against the flu virus. This study established that Aflunov should be given as two doses at least three weeks apart.

A third study, using a vaccine with strain A/turkey/Turkey/1/2005 (H5N1)-like strain (NIBRG-23), was carried out in 343 adults aged below and above 60 years. The study showed that 21 days after the second injection, around 70% of adults below 60 years and around 64% of adults above 60 years produced an acceptable antibody response.

The most common side effects with Aflunov (which may affect more than 1 patient in 10) are headache, myalgia (muscle pain), reactions at the site of injection (swelling, pain, induration and redness) and fatigue (tiredness). For the full list of side effects of Aflunov, see the package leaflet.

Aflunov should not be given to patients who have had an anaphylactic reaction (severe allergic reaction) to any of the components of the vaccine, including those found at trace (very low) levels (egg or chicken protein, ovalbumin [a protein in egg white], kanamycin or neomycin sulphate [antibiotics], barium sulphate, formaldehyde and cetyltrimethylammonium bromide). However, it may be appropriate to give the vaccine to these patients during a pandemic, as long as facilities for resuscitation are available.

It was noted that it is likely that a H5N1 strain of influenza will cause a pandemic in the future and Aflunov was shown to produce sufficient antibodies to stimulate an immune response and protect against H5N1. The European Medicines Agency therefore decided that Aflunov’s benefits are greater than its risks and it can be authorised for use in the EU.

Recommendations and precautions to be followed by healthcare professionals and patients for the safe and effective use of Aflunov have been included in the summary of product characteristics and the package leaflet.

As for all medicines, data on the use of Aflunov are continuously monitored. Side effects reported with Aflunov are carefully evaluated and any necessary action taken to protect patients.

Aflunov received a marketing authorisation valid throughout the EU on 29 November 2010.