Sinovac Photo: Li Hao/GT

Editor's Note:

As one of the leading COVID-19 vaccine manufacturers in China, Sinovac has expanded its annual production capacity to 2 billion doses and offered its inactivated vaccines to over 16 countries and regions. The Global Times reporters Hu Yuwei and Leng Shumei (GT) recently talked to Yin Weidong (Yin), the CEO of the Sinovac, to learn more about his views on vaccine's safety and effectiveness, amid frequently novel coronavirus mutations, and the company's moves in making the vaccine more globally accessible.  

GT: How effective is Sinovac's COVID-19 vaccine against current mutations of the novel coronavirus? If its effectiveness is weakened, will you redesign or upgrade the vaccine?

Yin: One of the prerequisites for a vaccine redesign is that mutated strains become dominant. The vaccine we use now is still very effective against COVID-19 and other mutations of the novel coronavirus. Only a few countries are seeing endemic mutated virus strains. For most other countries, ramping up efforts in mass and rapid vaccination is the key.

We are now intensively monitoring how the novel coronavirus mutates, closely working with Chinese leading scientists and national institutions on laboratory studies to track every change, and to discuss any potential treatment.

Current figures show that the protection rate of Sinovac vaccines within two months after administering two shots is 80-90 percent, but the number of antibodies in recipients declines with time. 

We are now analyzing data on protection rates after six months as well as conducting experiments on administering the third injection to recipients to see if there is a higher protection level. Some results are expected to come out soon.

GT: How long does it take to recalibrate or update your vaccine if there is a need?

Yin: Re-calibrating the vaccine would require re-engineering the mutated strain. The government also needs to reassess quality standards and regulatory policies used for the new vaccine. If the degree of variation is not large, there may be no need for adjustment; if the degree of variation is serious, the adjustment then requires cooperation from multiple parties.

Currently, our COVID-19 vaccine can cover major novel coronavirus variants. Even if a new variant occurs, vaccine producers can quickly update vaccines to contain it. 

GT: Some cities, including Beijing and Shanghai, plan to expand vaccination to children and the elderly. Do you have any data on the efficacy of the vaccine in the corresponding population? When do you expect results?

Yin: We have collected enough data to prove our vaccine's safety on the senior people and our vaccine is allowed to be used on the group pending emergency use approval. The exclusion of the older demographic from vaccination coverage is based on the consideration of the pandemic situation rather than the safety of the vaccine.  

China's success in controlling the pandemic has created a good environment for the country to carry out mass vaccination in an orderly fashion, starting from people working in high-risk industries and gradually expanding to low-risk demographics.

As for seniors, Sinovac has basically completed Phase II clinical trials on the group and the results are expected to come out in March. The company will submit the results to various countries' drug authorities and the vaccine will be allowed for use on seniors in these countries after obtaining approval.

Sinovac has started to vaccinate the elderly in Turkey and other countries, and we feel very excited to see that the 80-year-old Brazilian football icon Edson Arantes do Nascimento Pele was vaccinated with Sinovac's vaccine and expressed confidence in it.

GT: A 63-year-old Hong Kong resident developed shortness of breath two days after vaccination and was admitted to the hospital for treatment, but passed away on the same day. Hong Kong has reported more than one case of death after receiving the shot. How do you respond to the local public concern over the Sinovac's vaccine?

Yin: Vaccines will be administered among healthy people. Healthy people are those in relatively good health. But there will still be various diseases among these people. After mass inoculation drive, what we call Pharmacovigilance or abnormal reaction monitoring will be in progress at Sinovac.

At present, we have collected data on adverse reactions from tens of millions of people after inoculation. But in fact, all kinds of medical problems among people who get inoculated are normal.

We will intensively follow up on the investigation results. But local health administration and professional departments will be key in making decisions and judgments. 

We are confident in the overall safety of the Sinovac vaccine as it was proven to be safe from the observations of mass vaccinations.

GT: There is a great demand for Chinese vaccines at home and abroad. How do you balance the demand?

Yin: Vaccine distribution is a matter of multi-level cooperation among governments. With strong support from the Chinese government - ranging from scientific consulting to the use of Biosafety level 3 labs -- we are rapidly ramping up capacity from 1 billion to 2 billion to provide vaccines to more countries in line with the national strategy.

We usually export our vaccines to countries with large populations and a high prevalence of the COVID-19, and we are now gradually expanding the supply to some smaller neighboring countries.

Providing vaccines to more countries is also about protecting ourselves so that we can restore human and business links with others as soon as possible. 

GT: What are the most valuable points of your cooperation with other countries in phase three of the clinical trials overseas?

Yin: Partnering with other global scientific institutes, such as Brazil's Butantan Institute, a 120-year-old research Institute, and Indonesia's Biopharm, a 100-year-old vaccine company, as well as scientists from Turkey and Chile, is an important strategic concern. 

We experienced many hurdles for sure, including language barriers and differences in national standards of clinical and drug approval. But we have been promoting mutual recognition of scientific conclusions.

We closely work together to increase the accessibility of such a vaccine to make sure it can be delivered to a place 16,000 kilometers away from China in 2 to 8 degrees. These collaborations have provided us with valuable experiences. 

GT: The World Health Organization (WHO) sent a team to visit Sinovac's manufacturing plant in mid-February as a prerequisite to obtain WHO's pre-qualification. What was WHO's feedback after the visit? 

Yin: We have held dozens of meetings with the WHO at different levels in the past year, including high-level meetings at the governmental level and interdisciplinary meetings in professional fields. 

During the on-site inspection of the Sinovac's factory, the WHO gave us very pertinent and significant suggestions on improving medical quality. 

We will quickly receive the official evaluation document from the WHO team, and improve as requested by the suggestions. The WHO's approval is crucial for us as it will enable us to provide vaccines to more countries.

But we maintain bilateral cooperation with some other countries at the same time as it is a far more efficient way in certain circumstances. Experiences from both pathways are very valuable to us in working with others to stop the pandemic.