First RSV vaccine to protect infants up to 6 months of age and older adults

EMA has recommended granting a marketing authorisation in the European Union (EU) for Abrysvo, a vaccine to protect against disease caused by the respiratory syncytial virus (RSV). Abrysvo is the first RSV vaccine indicated for passive immunisation of infants from birth through 6 months of age following administration of the vaccine to the mother during pregnancy. This vaccine is also indicated for active immunisation of adults aged 60 years and older.

RSV is a common respiratory virus that usually causes mild, cold-like symptoms but it can cause serious consequences for children and older adults. In fact, in children RSV is a leading cause of paediatric hospitalisation in Europe. It may cause bronchiolitis and pneumonia and can lead to fatal respiratory distress.

RSV infection can also be serious for adults aged 50 years and older as it can cause acute respiratory infection, influenza-like illness or community-acquired pneumonia.

Abrysvo is a bivalent vaccine composed of two recombinant RSV fusion surface glycoproteins selected to optimise protection against RSV A and B strains. These proteins are essential for RSV to infect the body and are also the main targets of the antibodies generated to fight the infection.

Abrysvo was evaluated under EMA’s accelerated assessment mechanism because prevention of RSV disease is considered to be of major public health interest.

When a person is given the vaccine, their immune system generates specific antibodies and T cells (immune system cells) that help prevent RSV infection. In case of pregnant individuals, the neutralising antibodies cross the placenta, providing infants with protection up to 6 months after birth.

The opinion by EMA’s human medicines committee (CHMP) is based on data from two randomised, placebo-controlled, pivotal studies.

In one study, 3,695 individuals at 24-36 weeks pregnant were administered Abrysvo while 3,697 received a placebo (dummy injection). The assessment showed that the vaccine was effective in reducing both severe medically attended lower respiratory tract illness and medically attended lower respiratory tract illness occurring within 180 days after birth.

In the other study, 18,488 adults aged 60 years and older were administered the vaccine, while 18,479 received a placebo. The results of the study demonstrated efficacy for Abrysvo in the reduction of RSV-associated lower respiratory tract illness with 2 (or more) symptoms and with 3 (or more) symptoms.

The most common side effects reported in individuals between 24 and 36 weeks pregnant were vaccination site pain, headache and muscle pain. In individuals 60 years of age and older the most frequently reported side effect was vaccination site pain.

The opinion adopted by the CHMP is an intermediary step on Abrysvo’s path to patient access. The opinion will now be sent to the European Commission for the adoption of a decision on an EU-wide marketing authorisation. Once a marketing authorisation has been granted, decisions about price and reimbursement will take place at the level of each Member State, taking into account the potential role/use of this medicine in the context of the national health system of that country.

Note:

¹ The applicant for Abrysvo is Pfizer Europe MA EEIG.