(Bloomberg) -- China approved its first messenger RNA vaccine for Covid-19, clearing a shot from a local drugmaker that harnesses the powerful technology months after the world’s most-populous nation abandoned pandemic curbs.

The mRNA vaccine, developed by CSPC Pharmaceutical Group Ltd. and which targets the omicron variant, has been approved for emergency use, according to a statement from the company Wednesday to the Hong Kong stock exchange. Shares extended intraday gains to 7.7% before quickly paring most of that advance to trade 2.6% higher as of 1:15 pm in Hong Kong.

CSPC said the shot demonstrated an efficacy of between 70.2% and 85.3% up to four weeks following its use as a booster in a clinical trial involving 4,000 participants, though it’s not clear what the rates refer to. The company said the vaccine can be stored at 2C to 8C, but didn’t say for how long. 

The approval comes years after mRNA vaccines became commonplace across the rest of the world, and over three months after China became the last country to abandon strict Covid measures, resulting in a massive infection wave that may have caused at least hundreds of thousands of deaths, according to expert estimates. 

Low immunization rates for many high-risk elderly people and the waning protection of shots made with traditional inactivated technology potentially made China’s wave deadlier. Not having an mRNA vaccine was long considered a major lacuna for Beijing. The regulatory blessing for CSPC’s shot plugs that gap, while reinforcing the country’s reliance solely on homegrown vaccines to immunize its 1.4 billion population.

The Chinese government hasn’t approved the mRNA shot co-developed by BioNTech SE and Pfizer Inc., despite of a slew of data and applications filed by local partner Shanghai Fosun Pharmaceutical Group Co. It instead depended on inactivated vaccines developed by local state-owned drugmaker Sinopharm and the private firm Sinovac Biotech Ltd. for most of the pandemic.

The timing of the approval follows China’s post-Covid Zero case surge subsiding and many people have been granted a layer of natural immunity from their recent infection. The country’s abrupt pandemic pivot last year took many residents by surprise as officials had done little to boost inoculation rates, expand hospital capacity or secure adequate supplies of antivirals.

Instead, the virus was left to run rampant through a population with little previous exposure, overwhelming hospitals and crematoriums. Officially, just tens of thousands of people have died from Covid since the pandemic pivot in early December but experts say that’s likely an underestimate given the scale of the outbreak. Researchers in Hong Kong estimated in mid-December that almost 1 million people in China could die from Covid.

Read more: China’s Covid Death Tally Is Likely Just a Fraction of True Toll

--With assistance from Jinshan Hong and Abhishek Vishnoi.

(Updates to add details throughout)

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