(Bloomberg) -- Gritstone Bio Inc. will receive as much as $433 million from the US government to conduct a trial of its next-generation Covid-19 vaccine, a much-needed boost for the company struggling to find funds. 

Gritstone, based near San Francisco, has been working on a new Covid shot since at least 2021, but progress stalled as the small biotech struggled to find a partner. Project NextGen, a government initiative to advance Covid treatments and vaccines that recently doled out millions of dollars to Regeneron Pharmaceuticals Inc. and Johnson & Johnson for similar efforts, will fund the company’s 10,000-person study. 

The effectiveness of Covid vaccines from Moderna Inc. and the partnership of Pfizer Inc. and BioNTech SE dwindles in a matter of months. Early trials indicate that Gritstone’s vaccine helps generate more durable antibodies and broader T-cell protection, Chief Executive Officer Andrew Allen said in an interview earlier this month. In previously vaccinated older adults, it boosted antibodies for at least six months, according to interim results from a trial published in Nature Communications. 

The next step will be proving that those studies translate to real, lasting protection from disease, Allen said. He anticipates the next phase of the trial will take about a year.

“It’s within our grasp to make superior vaccines,” he said in the interview. 

The shares rose 40% as of 5:14 p.m. in New York, after the close of US markets. 

Gritstone’s shot is based on technology called self-amplifying messenger RNA. Vaccines made by Pfizer and Moderna exclusively target the virus’s spike protein, which mutates quickly. Gritstone’s next-generation shot engages slower-evolving regions of the virus and aims to engage other aspects of the immune system, namely killer T-cells, which can identify and destroy virus-infected cells. Allen said the technology also lends itself to potentially be used in a pan-coronavirus vaccine that would theoretically protect against all Covid variants. 

Read More: Moderna Poised to Seek Flu Shot Approval After Trial Results 

--With assistance from Riley Griffin.

(Updates with post-market trading in sixth paragraph.)

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