A Organização Mundial de Saúde (OMS) foi notificada da existência deste novo vírus a 31 de dezembro de 2019, uma vez que foi declarado um surto de casos de “pneumonia viral” em Wuhan (República Popular da China)¹. O número de casos confirmados aumentou repentinamente com milhares de novos casos diagnosticados diariamente durante o mês de janeiro, até 30 de janeiro de 2020, quando o surto de COVID-19 foi declarado pela OMS como uma emergência de saúde pública de importância internacional. Foi em 11 de março de 2020 que a OMS declarou oficialmente o estado da COVID-19 como uma pandemia global³.

A maioria das pessoas infetadas apresenta uma doença respiratória ligeira ou moderada e recupera sem a necessidade de nenhum tratamento especial. No entanto, alguns ficam gravemente doentes e precisam de cuidados médicos. Idosos e pessoas com condições de saúde subjacentes – como doenças cardiovasculares, diabetes, doenças respiratórias crónicas ou cancro – têm uma maior probabilidade de desenvolver a doença grave⁴. 

A COVID-19 espalha-se quando uma pessoa infetada exala pequenas partículas respiratórias e gotículas que contêm o vírus. Estas partículas e gotículas respiratórias podem ser inaladas por outras pessoas ou podem atingir os seus olhos, nariz ou boca. Em algumas circunstâncias, podem contaminar as superfícies que outras pessoas tocam. Qualquer pessoa infetada com COVID-19 pode transmitir a doença, mesmo que ela própria não apresente sintomas⁵.

Compromisso da HIPRA em relação à COVID-19

A HIPRA, com mais de 50 anos de experiência no combate a doenças transmissíveis através do desenvolvimento de vacinas, é uma empresa comprometida com a saúde, as pessoas, a sociedade e o progresso. Por esta razão, perante uma situação excecional, a HIPRA optou desde o início por contribuir com o seu know-how no combate à pandemia com o desenvolvimento de uma vacina de proteína recombinante contra o SARS-COV-2 (Autorização de Introdução no Mercado EMA a 31 de Março de 2023). 

- What is BIMERVAX® and what is it used for? 

BIMERVAX® is the vaccine developed by HIPRA to prevent COVID-19 in adults over 16 years of age. The vaccine is authorized as a booster dose for those who have already been immunized at least 6 months after a previous mRNA COVID-19 vaccine. The vaccine is based on a recombinant protein. Specifically, the vaccine is based on the receptor binding domain (RBD) of the virus surface, which is added to an adjuvant that amplifies the body's immunogenic response. 

- How is it used? 

The COVID-19 HIPRA’s vaccine is given as an injection, usually in the muscle of the upper arm. It is given as a booster at least 6 months after a previous mRNA COVID-19 vaccine. For more information about using it, see the package leaflet or consult a healthcare professional. 

- How does it work? 

BIMERVAX® works by preparing the body to defend itself against COVID-19. The vaccine contains a protein produced in the laboratory that consists of part of the SARS-CoV-2 spike protein from the virus. It also contains an ‘adjuvant’, a substance to help strengthen the immune response to the vaccine. When a person is given the vaccine, their immune system will identify the combined protein as foreign and produce natural defenses — antibodies and T cells — against it. If, later on, the vaccinated person comes into contact with SARS-CoV-2, the immune system will recognize the spike protein on the virus and be prepared to attack it. The antibodies and immune cells can protect against COVID-19 by working together to kill the virus, prevent its entry into the body’s cells and destroy infected cells. 

- What benefits of BIMERVAX® have been shown in studies? 

The benefits of this vaccine were assessed in an immunobridging study, which compared the immune response induced by this new vaccine with that induced by the authorised mRNA vaccine Comirnaty, which targets the original (Wuhan) SARS-CoV-2 spike protein. The study involved 765 adults who had previously completed primary vaccination with 2 doses of Comirnaty and who were subsequently given a booster dose of either BIMERVAX® or Comirnaty. Although BIMERVAX® triggered the production of lower levels of antibodies against the original strain of SARS-CoV-2 than Comirnaty, it led to higher levels of antibodies against the Beta and Omicron variants and comparable levels against the Delta variant. Supportive data were provided from an ongoing study that included 36 adolescents aged 16 to 17 years old, with immune response data available for 11 of them. This study found that BIMERVAX® given as a booster produced an adequate immune response in these adolescents, with antibody production comparable to that seen in adults who received BIMERVAX®.

 - What are the risks associated with BIMERVAX®? 

The most common side effects (which may affect more than 1 in 10 people) are pain at the injection site, headache, tiredness and muscle pain. Lymphadenopathy (enlarged lymph nodes), diarrhoea, vomiting, nausea (feeling sick), fever, pain in the armpits and reddening, hardness or swelling at the injection site may affect less than 1 in 10 people. Other less frequent adverse effects may affect less than 1 in 100 people are listed in the SmPC. Allergic reactions may occur. As for all vaccines, BIMERVAX® should be given under close supervision with appropriate medical treatment available. 

- Why is BIMERVAX® authorized in the European Union?

 Based on data comparing the immune response triggered by BIMERVAX® with that triggered by an authorised mRNA COVID-19 vaccine, EMA concluded that BIMERVAX® is expected to be at least as effective as the comparator at restoring protection against COVID-19 in people aged 16 years and older. The safety profile of BIMERVAX® is comparable to that of other COVID-19 vaccines. The most common side effects seen with BIMERVAX® were usually mild to moderate and cleared within a few days after vaccination. EMA therefore decided that BIMERVAX®’s benefits are greater than its risks and that it can be recommended for authorisation in the EU. BIMERVAX® received a marketing authorisation valid throughout the EU on 30 March 2023. Further information on HIPRA’s COVID-19 vaccine can be found on the European Medicines Agency website: ema.europa.eu/medicines/human/EPAR/bimervax

Referências bibliográficas:

^{1. World Health Organization. Basic information about COVID-19. [Internet] Disponível em: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/question-and-answers-hub/q-a-detail/coronavirus-disease-covid-19 (último acesso: 8 de março de 2023)}

^{2. “Information for the public. Questions and Answers about the new COVID-19 Coronavirus [Internet]”. Disponível em: https://www.sanidad.gob.es/en/profesionales/saludPublica/ccayes/alertasActual/nCov/ciudadania.htm (última visita: 8 de março de 2023)}

^{3. Hu B, Guo H, Zhou P, Shi ZL. Characteristics of SARS-CoV-2 and COVID-19. Nat Rev Microbiol. 2021;19(3):141-154.}

^{4. World Health Organization. Coronavirus. [Internet] Disponível em: https://www.who.int/health-topics/coronavirus#tab=tab_1 (última visita: 8 de março de 2023)}

^{5. Centres for Disease Control and Prevention. [Internet]. Disponível em: https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/how-covid-spreads.html (última visita: março de 2023)}

^{6. World Health Organization. Questions and answers about the spread of COVID-19. [Internet] Disponível em:  https://www.who.int/news-room/questions-and-answers/item/coronavirus-disease-covid-19-how-is-it-transmitted (última visita: março de 2023)}