KUALA LUMPUR: Sinovac Biotech Ltd, the developer of CoronaVac COVID-19 vaccine, has defended the efficacy of its two-dose vaccine including against the Delta variant.

Company spokesperson Liu Peicheng said although no data is available on its protective effect yet, studies have proven the vaccine's efficacy in countries such as Brazil, Indonesia, Chile and Turkey where the vaccine has been widely used.

"It was more than 90 per cent effective against severe infection and hospitalisation. We also noticed that the infection rate after vaccination has been very low in these countries, and the symptoms too very mild in most circumstances.

"Although there is a reduction in its neutralising effect, Sinovac's current vaccine (CoronaVac) remains effective against the Delta variant," said Liu, who is based at the company's headquarters in Beijing, in his written reply to questions posed by Bernama.

Sinovac's CoronaVac, is an inactivated vaccine and one of the most widely used COVID-19 vaccine worldwide. However, of late there have been concerns over its efficacy especially over the more contagious variants like Delta.

On July 16, the Malaysian government said it would phase out the use of Sinovac's vaccine under the National COVID-19 Immunisation Programme (PICK). However, 14 million doses of the vaccine will still be available to interested states and private companies from this month to September.

Meanwhile, on the need for booster shots Liu said though Sinovac's research has shown significant increase in antibody levels after the third dose, the company is still studying the necessity for it and the procedures involved.

" Sinovac is actively conducting clinical research using the new variant-specific vaccines as a third shot to boost immunity.

The new vaccines will provide higher protection specifically against the Gamma variant and the highly contagious Delta variant.

"Upon completion of the research, we will consider whether there is a need to submit a third dose recommendation to the World Health Organisation (WHO) based on the findings," he said.

Drugmaker Pfizer and partner BioNTech had recently announced that they are seeking US and European regulators' approval to offer a booster shot, claiming evidence indicate even fully vaccinated people are at greater risk of infection as the vaccine's effectiveness dips after six months.

In the Southeast Asian region, Sinovac, the leading vaccine developer and manufacturer in China, has so far exported over 150 million doses of vaccine to countries including to Indonesia, Malaysia, the Philippines, Thailand, Cambodia and Singapore.

While in Malaysia, the Chinese company had entered into partnership with Pharmaniaga Bhd to supply in bulk 14 million doses of its Covid-19 vaccine for the latter's subsidiary, Pharmaniaga LifeScience Sdn Bhd (PLS), to conduct fill and finish production at its plant here.

The first batch of the vaccine, delivered on Feb 27, was successfully rolled out on March 18 under PICK with Pharmaniaga successfully supplying all the 12 million doses of the vaccine to the government this month, earlier than the original schedule.

To date, Liu said Sinovac has delivered a total of 16 million doses of ready-to-fill bulk and finished vaccine to Malaysia in the first half of 2021 and the company will deliver another three million doses of finished vaccine and 4.44 million doses of ready-to-fill bulk by this month.

"The cooperation between Sinovac and Pharmaniaga has been going smoothly. With the support of Sinovac, Pharmaniaga has boosted its vaccine fill-and-finish and testing capabilities, and the vaccines produced have been approved for use by the Malaysian National Pharmaceutical Regulatory Agency (NPRA).

"In the second half of 2021, Sinovac will continue to maintain close communication with Malaysia and do everything it can to fulfill the needs of Malaysia's vaccination programme," he added.

He added that the company, with its annual production capacity of up to two billion doses is able to support the vaccination programmes of many countries accordingly.

-- BERNAMA