Pharmacy expert opposes diluting BioNTech jabs for the very young

Hong Kong should not dilute the adult 30mg doses of BioNTech vaccines to one-tenth - or 3mg - for children six months to five years old, said William Chui Chun-ming, President of the Society of Hospital Pharmacists of Hong Kong.  

His comments came after health authorities announced that children between six months and three years old may receive mainland-made Sinovac vaccine from Wednesday, while authorities engage in talks with BioNTech’s maker to buy its toddler version that will give parents a second inoculation option.  

BioNTech has separate vaccines for adults, children, and toddlers. The toddler version is one-third of the children’s version.  

The government’s vaccine expert advisors have earlier suggested that authorities dilute the adult BioNTech dosage for kids’ use if the city cannot get ahold of the toddler version BioNTech vaccines.   

Speaking on a radio program this morning, the pharmacy expert backs authorities’ decision to inoculate young children with the Sinovac vaccine, which he believed the decision was made after a comprehensive review of relevant data.  

As for the BioNTech vaccine, Chui advised against diluting.  

He said the dosage for children below three is too low, and a slight deviation may have a massive effect on the safety and effectiveness of the jabs.  

“That is because BioNTech vaccine uses mRNA technology and tiny nanoparticles,” Chui said. “If only a very small amount of nanoparticles are used after dilution, we would be concerned about the vaccine’s stability as it may not trigger the sufficient immune response.”  

Chui said the toddler version jabs were available in places like Singapore and European countries, whereas the manufacturer has previously stated they could ensure sufficient supply.  

He called on the SAR government to explain to the general public the reason for the hold-up in providing the toddler BioNTech jabs.