What is Celvapan?

What is Celvapan?
Celvapan is a vaccine that is given by injection. It contains influenza (flu) viruses that have been inactivated (killed). Celvapan contains a flu strain called A/California/07/2009 (H1N1)v.

What is Celvapan used for?
Celvapan is a vaccine to protect against ‘pandemic’ flu. It should only be used for the influenza A (H1N1) pandemic that was officially declared by the World Health Organization on 11 June 2009. A flu pandemic happens when a new strain of flu virus appears that can spread easily from person to person because people have no immunity (protection) against it. A pandemic can affect most countries and regions around the world. Celvapan is given according to official recommendations.
The vaccine can only be obtained with a prescription.

How is Celvapan used?
Celvapan is given by injection into the shoulder muscle in two doses, at least three weeks apart.
How does Celvapan work?
Celvapan is a vaccine. Vaccines work by ‘teaching’ the immune system (the body’s natural defences) how to defend itself against a disease. Celvapan contains a virus called A(H1N1)v that is causing the current pandemic. The virus has been inactivated so that it does not cause any disease.
When a person is given the vaccine, the immune system recognises the inactivated virus as ‘foreign’ and makes antibodies against it. The immune system will then be able to produce antibodies more quickly when it is exposed to the virus again. This helps to protect against the disease.
The viruses used in Celvapan are grown in mammal cells (‘vero cells’), unlike those in some other flu vaccines, which are grown in hen’s eggs.

How has Celvapan been studied?
Celvapan was first developed as a ‘mock-up’ vaccine that contained an H5N1 strain of the flu virus called A/Vietnam/1203/2004. The company studied the ability of this mock-up vaccine to trigger the production of antibodies (‘immunogenicity’) against this strain of flu virus in advance of the pandemic.
Following the start of the current pandemic, the company replaced the virus strain in Celvapan with the H1N1 strain causing the pandemic, and presented data relating to this change to the Committee for Medicinal Products for Human Use (CHMP).
What benefit has Celvapan shown during the studies?
The mock-up vaccine was shown to bring about protective levels of antibodies in at least 70% of the people in which it was studied. In line with the criteria laid down by the CHMP, this demonstrated that the vaccine brought about an appropriate level of protection.
The CHMP was also satisfied that the change of strain to the H1N1 strain did not affect the characteristics of the vaccine.
What is the risk associated with Celvapan?
The most common side effect with Celvapan (seen in more than 1 people vaccinated in 10) is pain at the site of the injection. For the full list of all side effects reported with Celvapan, see the Package Leaflet.
Celvapan should not be given to people who have had an anaphylactic reaction (severe allergic reaction) to any of the components of the vaccine, or to any of the substances found at trace (very low) levels in the vaccine, such as formaldehyde, benzonase or sucrose.
However, it may be appropriate to give the vaccine to these patients during a pandemic, as long as facilities for resuscitation are available.

Why has Celvapan been approved?
The CHMP decided that, based on the information obtained with the mock-up vaccine and the information provided on the strain change, the benefits of Celvapan are greater than its risks for the prophylaxis of influenza in the officially declared H1N1 pandemic situation. The Committee recommended that Celvapan be given marketing authorisation.
Celvapan has been authorised under ‘Exceptional Circumstances’. This means that it has not yet been possible to obtain full information about the pandemic vaccine. Every year, the European Medicines Agency will review any new information that may become available and this summary will be updated as necessary.

What information is still awaited for Celvapan?
The company that makes Celvapan will collect information on the safety and effectiveness of the vaccine, and submit this to the CHMP for evaluation.

Which measures are being taken to ensure the safe use of Celvapan?
The company that makes Celvapan will collect information on the safety of the vaccine while it is being used. This will include information on its side effects and its safety in children, the elderly, pregnant women, patients with severe conditions and people who have problems with their immune systems.

Other information about Celvapan:
The European Commission granted a marketing authorisation valid throughout the EU for the H5N1 mock‑up vaccine for Celvapan to Baxter AG on 4 March 2009. The change to the marketing authorisation for the H1N1 virus was authorised by the European Commission on 6 October 2009. The full assessment report will be published shortly.

Partial protection of seasonal trivalent inactivated vaccine against novel pandemic influenza A/H1N1 2009: case-control study in Mexico City.

Partial protection of seasonal trivalent inactivated vaccine

against novel pandemic influenza A/H1N1 2009:

case-control study in Mexico City.

Garcia-Garcia L, Valdespino-Gómez JL, Lazcano-Ponce E, Jimenez-Corona A, Higuera-Iglesias A, Cruz-Hervert P, Cano-Arellano B, Garcia-Anaya A, Ferreira-Guerrero E, Baez-Saldaña R, Ferreyra-Reyes L, Ponce-de-León-Rosales S, Alpuche-Aranda C, Rodriguez-López MH, Perez-Padilla R, Hernandez-Avila M.
BMJ. 2009 Oct 6;339:b3928. doi: 10.1136/bmj.b3928.

Instituto Nacional de Salud Pública, Cuernavaca, Mor, Mexico.
OBJECTIVE: To evaluate the association of 2008-9 seasonal trivalent inactivated vaccine with cases of influenza A/H1N1 during the epidemic in Mexico. DESIGN: Frequency matched case-control study. SETTING: Specialty hospital in Mexico City, March to May 2009. PARTICIPANTS: 60 patients with laboratory confirmed influenza A/H1N1 and 180 controls with other diseases (not influenza-like illness or pneumonia) living in Mexico City or the State of Mexico and matched for age and socioeconomic status. MAIN OUTCOME MEASURES: Odds ratio and effectiveness of trivalent inactivated vaccine against influenza A/H1N1. RESULTS: Cases were more likely than controls to be admitted to hospital, undergo invasive mechanical ventilation, and die. Controls were more likely than cases to have chronic conditions that conferred a higher risk of influenza related complications. In the multivariate model, influenza A/H1N1 was independently associated with trivalent inactivated vaccine (odds ratio 0.27, 95% confidence interval 0.11 to 0.66) and underlying conditions (0.15, 0.08 to 0.30). Vaccine effectiveness was 73% (95% confidence interval 34% to 89%). None of the eight vaccinated cases died. CONCLUSIONS: Preliminary evidence suggests some protection from the 2008-9 trivalent inactivated vaccine against pandemic influenza A/H1N1 2009, particularly severe forms of the disease, diagnosed in a specialty hospital during the influenza epidemic in Mexico City.
PMID: 19808768 [PubMed - in process]

What is Reye Syndrome?

What is Reye syndrome?
Reye syndrome is a rare condition that affects the normal chemical balance in the body, resulting in damage to the brain, kidneys, and liver. It is primarily a children's disease, although it can occur at any age.
As the inflammation in the brain increases, the pressure inside of the head may also increase. The increased pressure in the head causes neurological changes in the child.
It has a very rapid onset that can cause the child to go into a coma, or can result in death within hours of the symptoms.

What causes Reye syndrome?
The exact cause of Reye syndrome is unknown. The more common cases of Reye syndrome occur in conjunction with a previous viral infection, such as the flu or chicken pox.
Reye syndrome usually affects children between the ages of four and 12, and is most common at age six.
Studies show that there is an association between the ingestion of products containing aspirin in children who have a viral illness and Reye syndrome. As a result, the Centers for Disease Control and Prevention (CDC) and the American Academy of Pediatrics (AAP) have released warnings to the public about the relationship between aspirin and Reye syndrome. Parents should not give aspirin to children unless instructed by your child's physician.

What are the symptoms of Reye syndrome?
The following are the most common symptoms of Reye syndrome. However, each child may experience symptoms differently. A child may have had a viral illness such as a respiratory infection, chickenpox, or diarrhea before experiencing symptoms of Reye syndrome. Symptoms may include:

• a full or bulging fontanelle (a soft spot on the top of the head in infants)
• sleepiness or lethargy
• sudden and prolonged vomiting
• combative behavior
• rapid breathing and heart rate
• seizures
• coma
• increased intracranial pressure
• increased irritability
• high-pitched cry

The symptoms of Reye syndrome may resemble other conditions or medical problems. Always consult your child's physician for a diagnosis.

How is Reye syndrome diagnosed?
The diagnosis of Reye syndrome is made after the sudden onset of specific symptoms and after diagnostic testing. During a physical examination, your child's physician obtains a complete medical history of your child. Your child's physician may also ask if the child has recently had a cold or other viral illness, and whether the child has taken aspirin or medication containing aspirin. Diagnostic tests that may be performed to confirm the diagnosis of Reye syndrome include the following:

• blood and liver function tests
• urine and stool tests
• liver biopsy - a small amount of tissue is removed from the liver and studied to help diagnose different illnesses.
• electroencephalogram (EEG) - a procedure that records the brain's continuous, electrical activity by means of electrodes attached to the scalp.
  lumbar puncture (spinal tap) - a special needle is placed into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. A small amount of cerebral spinal fluid (CSF) can be removed and sent for testing to determine if there is an infection or other problems. CSF is the fluid that bathes your child's brain and spinal cord.
• intracranial pressure monitoring (ICP) - measures the pressure inside of the child's head.
  

Treatment of Reye syndrome:
Specific treatment for Reye syndrome will be determined by your child's physician based on:

• your child's age, overall health, and medical history
• the extent of the condition
• your child's tolerance for specific medications, procedures, or therapies
• expectations for the course of the condition
• your opinion or preference
  

Although there is no cure for Reye syndrome, there are some treatment options. The key to medically managing Reye syndrome is early detection.

A child with Reye syndrome requires immediate hospitalization in the intensive care unit and close monitoring by the healthcare team. This is a serious illness that can quickly worsen.
The goal of treatment is to monitor and reduce the pressure in the head and to provide supportive care (treatment of symptoms) to the child. Medications are used to control the inflammation in the brain, seizures, fever, or other conditions that may be present.
The extent of the problem is dependent on the severity of the condition and the presence of other organ system problems that could affect the child. In severe cases, a breathing machine may be required to help the child breathe easier.

Prevention of Reye syndrome:
Parents should read medication labels carefully and avoid giving children products containing aspirin during times of illness. Consult your child's physician for questions regarding medications and dosage.