Merck's Imported Hepatitis A Vaccine to Exit Chinese Market

Interface News reporter |Li Kewen

Interface News Editor |Xie Xin

Jiemian News learned from multiple sources that MSD is about to halt its hepatitis A vaccine.Vicant®Supply in the Chinese market.

Staff from a CDC in East China confirmed to Interface News that MSD is preparing to suspend the supply of inactivated hepatitis A vaccines within mainland China, though the subsequent usage of already delivered stock remains unclear. Interface News also obtained similar statements from the Shunyi District Community Health Service Center in Beijing. Staff there also indicated that the imported MSD inactivated hepatitis A vaccine will soon be withdrawn from the market.

On March 27, MSD China confirmed to Interface News,MSD, based on the adjustment of global commercial strategy, careful evaluation of existing R&D and production resources, and full consideration that locally produced products can meet market demand, has now made a business adjustment decision to cease supplying Vicate to the Chinese market effective immediately.®。

Jiemian News previously reported that MSD's imported inactivated hepatitis A vaccine has been out of stock in many places in China, including Beijing, Shanghai, Guangzhou, Xi'an, Chengdu, and more. Many people who have received the first dose of MSD's inactivated hepatitis A vaccine recently expressed on social media platforms that after completing the first dose of MSD's inactivated hepatitis A vaccine, they were informed by the local community health service center that the vaccine was out of stock when they went to receive the second dose.

On February 29, regarding the widespread shortage of imported inactivated hepatitis A vaccines in China, MSD China exclusively responded to Interface News, stating that a new batch of MSD's inactivated hepatitis A vaccine had completed batch release and entered the distribution stage this month. MSD will continue to evaluate the production and supply chain situation of the vaccine and make corresponding business decisions.

Regarding the previous shortage, MSD stated, "The production of vaccine products is highly complex and requires strict quality control. The supply of imported vaccine products is generally also affected and restricted by logistics, transportation, and other force majeure factors."

Previously, it had not been approved for issuance for more than half a year.

Previously, an industry insider revealed to The Paper that the registration certificate for MSD's imported inactivated hepatitis A vaccine is about to expire, and MSD will not renew it, which means this product will be withdrawn from the Chinese market.

Jiemian News queried the National Medical Products Administration and found that MSD has four specifications of imported inactivated hepatitis A vaccine products approved, which are 1 vial/box (25U/0.5ml/vial), 10 vials/box (25U/0.5ml/vial), 1 vial/box (50U/1.0ml/vial), and 10 vials/box (50U/1.0ml/vial), respectively.

The registration certificates for these four specifications of imported inactivated hepatitis A vaccines will all expire on July 15, 2025. This also means that after July 15 next year, this product will no longer be able to be newly imported.

During the final period of the registration certificate, MSD no longer made efforts in the registration, promotion, and sales of the imported inactivated hepatitis A vaccine.

According to statistics from The Paper on the batch release of biological products by the National Institutes for Food and Drug Control in 2023, MSD's inactivated hepatitis A vaccine received only two batches of batch release throughout 2023, both in the first half of the year, including one batch in February and one batch in June.

By the second half of 2023, MSD's inactivated hepatitis A vaccine had not received any new batch release. In addition, The Paper compared the agents of MSD's hepatitis A vaccine.ZHIFEI BIOLOGICALThe annual report also found that 2023 was the year with the lowest number of approvals for MSD's inactivated hepatitis A vaccine in the past five years, with only 311,400 doses approved.

MSD China's latest national vaccine batch release data for February 2024 shows that batches of MSD's imported inactivated hepatitis A vaccine have completed batch release and entered circulation. However, MSD did not disclose the specific quantity of this batch of inactivated hepatitis A vaccine.

According to the statistics of The Paper, as of February 27, six companies in China have obtained approval for the marketing of hepatitis A vaccines, of which five are local enterprises and one is a foreign-funded enterprise. The five local enterprises are Sinovac Biotech, Institute of Medical Biology of the Chinese Academy of Medical Sciences, Aleph Biotechnology, and Zhejiang Pukang.Kang ShengProducts and Changchun Biologics. The only foreign company is MSD.

According to the statistics on the batch release of biological products in 2023 by the National Institutes for Food and Drug Control, Sinovac Biotech, Changchun BCHT Biotechnology, and AIM Vaccine accounted for 27%, 23%, 15%, 18%, and 15% respectively. Among them, Sinovac Biotech had the highest number of approvals at 28 times, followed by Changchun BCHT Biotechnology with 24 approvals.

The second dose can be replaced with a domestically produced vaccine.

The biggest impact of MSD's withdrawal of imported inactivated hepatitis A vaccine from China is that some children have already received the first dose of the imported inactivated hepatitis A vaccine, and after the vaccine is withdrawn from the market, how should the children continue with the second dose of the inactivated vaccine.

The hepatitis A vaccine is prepared using the hepatitis A virus strain and can stimulate the body to produce immunity against the hepatitis A virus, for the prevention of hepatitis A.

According to the production process, there are two types: live attenuated hepatitis A vaccine and inactivated hepatitis A vaccine. Both the inactivated hepatitis A vaccine and the live attenuated hepatitis A vaccine are based on human diploid cells. Overall, the inactivated hepatitis A vaccine has fewer safety issues, is more biologically stable, and is easier to store.

MSD's imported hepatitis A vaccine adopts the inactivated vaccine technology.

The live attenuated hepatitis A vaccine is suitable for individuals over 1.5 years old who are susceptible to hepatitis A, with the same dosage for both children and adults, administered as a single dose. The inactivated hepatitis A vaccine is suitable for individuals over 1 year old who are susceptible to hepatitis A, available in adult and pediatric formulations. It is administered in two doses, with an interval of ≥6 months between the two doses.

In general, parents should allow children to complete the full vaccination schedule using the same type of vaccine produced by the same manufacturer. However, if circumstances do not permit, the following principles can be followed.

According to the "National Immunization Program Vaccine Child Immunization Schedule and Instructions (2021 Edition)", if one dose of inactivated hepatitis A vaccine has been administered but there are no conditions to administer the second dose of inactivated hepatitis A vaccine, one dose of attenuated live hepatitis A vaccine can be administered to complete the catch-up vaccination, with an interval of no less than 6 months.

The "Immunization Schedule and Instructions for Children under the National Immunization Program (2021 Edition)" also specifies that when it is impossible to complete the vaccination schedule using the same vaccine from the same manufacturer, vaccines of the same type from different manufacturers can be used to complete subsequent vaccinations.

Relevant clinical research data have proven that the immune effects and safety of domestically produced live attenuated hepatitis A vaccines and inactivated hepatitis A vaccines are not inferior to imported inactivated hepatitis A vaccines.

According to the article "Evaluation of Immunogenicity and Safety of Chinese Live Attenuated and Inactivated Hepatitis A Vaccines" published in the Chinese Journal of Epidemiology in 2013. The article used imported inactivated hepatitis A vaccine as a positive control to evaluate the immunogenicity and safety of Chinese live attenuated and inactivated hepatitis A vaccines.

Immunogenicity showed that two weeks after vaccination, the seroconversion rates of Chinese-produced live attenuated hepatitis A vaccine and inactivated vaccine were 85.00% and 94.59%, respectively; by the fourth week after vaccination, the seroconversion rate reached 100%; twelve months after vaccination, the level of hepatitis A antibody in the group vaccinated with Chinese-produced inactivated hepatitis A vaccine was higher than that in the group vaccinated with imported inactivated hepatitis A vaccine.

Safety results showed that no serious adverse reactions were found in any group. Adverse reactions mainly included fever, pain at the vaccination site, and induration. The incidence of adverse reactions in the domestically produced live attenuated hepatitis A vaccine group and the inactivated vaccine group was 13.95% and 15.25%, respectively, while it was 16.80% in the imported inactivated hepatitis A vaccine group. There was no statistically significant difference among the groups.

In other words, if a child receives an imported inactivated hepatitis A vaccine for the first dose, parents can rest assured to let the child receive a domestically produced inactivated hepatitis A vaccine as a substitute when the time for the second dose arrives.