Chinese vaccine maker Clover Biopharmaceuticals raised $240 million in an initial public offering in Hong Kong on November 4, giving the Chengdu-based firm a valuation of nearly $2 billion. On the first day of trading on November 5, shares dipped 5% below their IPO price of HK$13.38 ($1.72).

Clover, founded in 2007 by a former Vanderbilt University biochemistry professor named Dr. Peng Liang, has never reported operating profit and does not have a single approved product on the market. But as its IPO prospectus makes clear, it sought to sell investors on the promise of its protein-based COVID-19 vaccine. The jab performs particularly well against the Delta variant and could boost the global vaccination campaign.

“We expect to address the significant global need for COVID-19 vaccines with our near-commercial protein-based COVID-19 vaccine candidate," the company said in its prospectus.

The protein-based technology of Clover's candidate is similar to what's in Novavax's COVID-19 vaccine. The jab by Novavax, a U.S. company, produced promising trial results but has earned approval only in Indonesia amid regulatory and manufacturing delays. Clover’s two-dose vaccine—called SCB-2019—contains fragments of COVID-19 that do not cause disease but help stimulate an immune response against the virus. China's Anhui Zhifei Longcom and Taiwan's Medigen have also released successful protein-based candidates, but neither has been approved by a global medical body like the World Health Organization.

In September, Clover released results for Phase II and III trials of its COVID-19 vaccine. The trials, which included 30,000 people on five continents, found the vaccine to be 67% effective in preventing COVID-19 infections, and 100% effective in preventing severe cases and deaths. The trials tested the vaccine against several variants of the virus, including Delta. Against the Delta variant alone, the vaccine provided a higher level of protection. It was 79% effective in preventing Delta-variant infections, compared to 58% effective against the Mu variant.

“This very encouraging [Phase II/III] data demonstrates the favorable safety profile of Clover’s vaccine and its efficacy against multiple variants of SARS-CoV-2—including the predominant Delta variant—so it will be a crucial addition to our weaponry in the fight against COVID-19,” Richard Hatchett, CEO of Coalition for Epidemic Preparedness Innovations (CEPI), said in a statement in September.

CEPI, a research group that's partially backed by the Bill & Melinda Gates Foundation, has partnered with Clover to develop a viable COVID-19 candidate. CEPI granted Clover $360 million in 2020 to fund research and trials for its vaccine.

In June, Gavi, a vaccine alliance that also receives funding from the Gateses and works closely with CEPI, announced that it would purchase 414 million doses of Clover’s vaccine between 2021 and 2022 to contribute to COVAX. COVAX, a global initiative to provide vaccines to lower- and middle-income countries, has been plagued by supply issues as wealthy countries have gobbled up the vast majority of jabs.

Distribution of Clover's COVID-19 vaccine through COVAX would require WHO approval, and it’s unclear when that may arrive. Clover has reportedly started to apply to the WHO, European Union, and China for approval of its vaccine. In its prospectus, Clover said it expected to obtain “conditional approvals” for market release between the fourth quarter of 2021 and the middle of next year, but Clover's vaccine hasn't gotten the green light anywhere yet.

"We are excited at what the future holds as we submit conditional regulatory approval applications for and potentially commercialize [Clover's COVID jab] in the near term," Clover CEO Joshua Liang said in a statement on November 5.

Clover did not respond to Fortune’s request for comment.

Clover recently told Nikkei Asia that it expects to have the capacity to produce 1 billion doses per year at an unspecified date in one factory in China. Novavax, with its similar vaccine technology, has struggled with quality issues while attempting to ramp up vaccine production capacity.

In addition to its COVID-19 vaccine, Clover says that it has multiple other drugs in development, including therapies for cancer and arthritis. But all its non-COVID-related drugs are still in clinical development and do not have timelines yet for market release.