The opinion was based on the results of clinical trials carried out in children in a range of countries outside the EU, which showed that there was an adequate immune response against all six diseases in all major ethnic groups. All of the active substances in the vaccine have already been used in other vaccines, except for the hepatitis B component.

The evaluation team included experts from Brazil and Thailand nominated by the WHO and an expert from the WHO's vaccine prequalification programme.

Hexaxim can be used as primary or a booster vaccination. The primary vaccination is in accordance with the WHO's expanded Programme on Immunization schedule. The vaccine is given as three doses at least four weeks apart. The most common side effects in clinical trials were pain and redness at the injection site, irritability and crying.