German company BioNTech has said it still hopes to have its Covid-19 vaccine approved in China, despite the process having been stalled for months. Approval of the vaccine was “extremely important” but the outcome of China’s regulatory review was “very difficult to predict”, Sean Marett, the firm’s chief commercial officer, was quoted by Reuters as saying at a health care conference on Tuesday. “It is a continued dialogue with the Chinese authorities,” Marett said. “China remains extremely important to us, and we are committed [to the review].” The company’s vaccine is widely available internationally but has yet to receive any regulatory approval in mainland China, despite Chinese firm Shanghai Fosun Pharmaceutical distributing it in Hong Kong, Macau and Taiwan. Made using mRNA technology , it is distributed elsewhere by Pfizer. The lack of approval in mainland China for one of the world’s most widely used and effective vaccines has been striking, especially as mRNA doses have been given as boosters in other countries that – like China – relied initially on jabs made using the inactivated virus method. The highly transmissible Omicron variant, which can also evade immunity given by vaccines or past infections, has raised the urgency of giving booster shots. “China and Russia are the last two major countries that have not approved BioNTech, which is actually much better than the inactivated vaccines, as shown by the data from everywhere,” said virologist Jin Dong-Yan, a professor with the University of Hong Kong. “There is no scientific reason BioNTech cannot be approved in China. The Chinese authorities should immediately approve the BioNTech application – the sooner the better.” Inactivated vaccines developed by Chinese firms Sinopharm and Sinovac have been used in China’s vaccination campaign and exported widely. Various laboratory studies have shown that giving three inactivated doses does not produce enough antibody protection against Omicron, and that giving mRNA boosters after two inactivated doses offers much stronger protection. In one study, by Yale University, researchers even believed that two doses of an mRNA vaccine was sufficient. China has maintained its zero-Covid approach , using mass testing and strict restrictions on movement to quickly contain transmission where cases are detected. But it is battling outbreaks of the Delta and Omicron variants at the same time, and both continue to spread. In the city of Xian, which has been in full lockdown for over a fortnight, more than 2,000 cases have been reported since early December. Meanwhile, in the northern port of Tianjin, the country’s first known Omicron outbreak has infected more than 100 people and spread to several other cities . BioNTech had initially said last year that approval for its jabs in mainland China was expected as early as July. Omicron: what we know so far about symptoms, transmissions, vaccines Shanghai Fosun has completed animal trials and early-stage human trials in the mainland, as requested in preparation for approval. The Chinese company also agreed last May to form a US$200 million joint venture with BioNTech to build a plant in China capable of supplying up to 1 billion Covid-19 vaccine doses a year. Fosun was to contribute funding and premises, and BioNTech the licence and know-how. Last June, Fosun chairman Wu Yifang told shareholders that the production line would be ready for test production in August, and that Fosun was working on technology transfer, buying equipment and sourcing raw materials. BioNTech sent experts to Shanghai to help the preparations. Wu said that Fosun had completed a technical review and was awaiting an administrative review – which has been stalled ever since.