Singapore, like the World Health Organisation and the United States, will only approve Covid-19 vaccines that are at least 50 per cent effective, said Health Minister Gan Kim Yong.
He was responding yesterday to Workers' Party chairman Sylvia Lim (Aljunied GRC), who had asked if the Health Sciences Authority (HSA) has any thres-hold for efficacy before it approves any vaccine.
At the same time, other criteria must also be considered before approving a vaccine in a crisis situation like the pandemic, Mr Gan noted.
HSA's experts will weigh the benefits and risks, and conduct a holistic assessment before concluding whether a vaccine will be approved for use, he added.
This includes factors such as the potential risk of adverse incidents.
"So it is not a clear-cut thres-hold that once (the efficacy) is 50.1 per cent, we will approve it. If there is greater uncertainty, then we will require a higher level of efficacy for us to be assured of the benefits versus the risks," Mr Gan said.
Also, the severity of the health crisis will have to be taken into account.
A lower threshold of efficacy may be accepted in the event of a very severe pandemic that requires the population to be vaccinated as quickly as possible.
The Covid-19 vaccine developed by Pfizer and BioNTech - the first one to be approved here - has demonstrated an efficacy rate of 95 per cent in clinical trials on more than 40,000 participants aged between 16 and 91 years old.
Ms Lim noted that HSA's approval for the Pfizer-BioNTech vaccine is an interim authorisation, and asked what additional information will need to be submitted in order for the vaccine to receive full registration.
In response, Mr Gan said the authorities will have to monitor how the vaccine is administered in real life, given that it has been rolled out for only a couple of months.
The manufacturers are also required to report any adverse incidents that happen so that Singapore can keep track of the vaccine's performance on the ground, as well as the potential risks that it may carry.
"We need to do this continuously for a prolonged period of time, usually one year, two years or maybe longer, so as to give us the assurance of the long-term effect of this vaccine," said Mr Gan, adding that this is partly why HSA has not yet given full authorisation to the vaccine.
A full authorisation will require long-term data to be available.
"But in view of the pandemic that we are facing today, HSA has given the interim approval for the use of this vaccine, accepting the fact that long-term data will only be available in the long term," said Mr Gan.
