Moderna said Monday its COVID-19 vaccine is proving highly effective in a major trial, a second ray of hope in the global race for a shot to tame a resurgent virus that is now killing more than 8,000 people a day worldwide.

The company said its vaccine appears to be 94.5% effective, according to preliminary data from Moderna’s ongoing study. A week ago, competitor Pfizer Inc. announced its own vaccine appeared similarly effective — news that puts both companies on track to seek permission within weeks for emergency use in the U.S.

The results are “truly striking,” said Dr. Anthony Fauci, the U.S. government's top infectious diseases expert. Earlier this year, Fauci said he would be happy with a COVID-19 vaccine that was 60% effective.

A vaccine can’t come fast enough, as virus cases topped 11 million in the U.S. over the weekend — 1 million of them recorded in just the past week — and governors and mayors are ratcheting up restrictions ahead of Thanksgiving. The pandemic has killed more than 1.3 million people worldwide, over 245,000 of them in the U.S.

Stocks rallied on Wall Street and elsewhere around the world on rising hopes that the global economy could start returning to normal in the coming months. Moderna was up 7.5% in the morning, while companies that have benefited from the stay-at-home economy were down, including Zoom, Peloton and Netflix.

Dr. Stephen Hoge, Moderna’s president, welcomed the “really important milestone” but said having similar results from two different companies is what’s most reassuring.

“That should give us all hope that actually a vaccine is going to be able to stop this pandemic and hopefully get us back to our lives,” Hoge told The Associated Press. He added: “It won’t be Moderna alone that solves this problem. It’s going to require many vaccines” to meet the global demand.

The National Institutes of Health helped create the vaccine Moderna is manufacturing, and NIH's director, Dr. Francis Collins, said the exciting news from two companies “gives us a lot of confidence that we're on the path towards having effective vaccines.”

But “we're also at this really dark time,” he warned, saying people can't let down their guard during the months it will take for doses of any vaccines cleared by the Food and Drug Administration to start reaching a large share of the population.

Scientists not involved with the testing were encouraged by the early findings but cautioned that the FDA still must scrutinize the safety data and decide whether to allow vaccinations outside of a research study.

“We’re not to the finish line yet,” said Dr. James Cutrell, an infectious disease expert at UT Southwestern Medical Center in Dallas. “If there’s an impression or perception that there’s just a rubber stamp, or due diligence wasn’t done to look at the data, that could weaken public confidence.”

If the FDA allows emergency use of Moderna’s or Pfizer’s candidate, there will be limited, rationed supplies before the end of the year.

Both vaccines require people to get two shots, several weeks apart. U.S. officials said they hope to have about 20 million Moderna doses and another 20 million doses of the vaccine made by Pfizer and its German partner BioNTech to use in late December.

Exactly who is first in line is yet to be decided. But Health and Human Services Secretary Alex Azar said the hope is that enough doses are available by the end of January to vaccinate adults over 65, who are at the highest risk from the coronavirus, and health care workers. Fauci said it may take until spring or summer for enough for anyone who is not high risk and wants a shot to get one.

States are gearing up for what is expected to be the biggest vaccination campaign in U.S. history. First the shots have to arrive where they're needed, and Pfizer's must be kept at ultra-cold temperatures — around minus 94 degrees Fahrenheit. Moderna's vaccine also starts off frozen, but the company said Monday it can be thawed and kept in a regular refrigerator for 30 days, easing that concern.

Another important message: Additional vaccines that work in different ways are still in testing — and despite the promising news about Moderna's and Pfizer's shots, more volunteers are needed for those studies.

Moderna’s vaccine is being studied in 30,000 volunteers who received either the real thing or a dummy shot. On Sunday, an independent monitoring board examined 95 infections that were recorded after volunteers' second shot — and only five of the illnesses occurred among people given the real vaccine.

The study is continuing, and Moderna acknowledged the protection rate might change as more COVID-19 infections are detected. Also, it’s too soon to know how long protection lasts. Both cautions apply to Pfizer’s vaccine as well.

But Moderna’s independent monitors reported some additional, promising tidbits: All 11 severe COVID-19 cases were among placebo recipients, and there were no significant safety concerns. The main side effects were fatigue, muscle aches and injection-site pain after the second dose.

The Cambridge, Massachusetts, company's vaccine is among 11 candidates in late-stage testing around the world, four of them in huge studies in the U.S.

Both Moderna's shots and the Pfizer-BioNTech candidate are so-called mRNA vaccines, a brand-new technology. They aren’t made with the coronavirus itself, meaning there’s no chance anyone could catch it from the shots. Instead, the vaccine contains a piece of genetic code that trains the immune system to recognize the spiked protein on the surface of the virus.

Pfizer CEO Albert Bourla tweeted that that he was thrilled at Moderna’s news, saying, “Our companies share a common goal — defeating this dreaded disease.”

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The Associated Press Health and Science Department receives support from the Howard Hughes Medical Institute’s Department of Science Education. The AP is solely responsible for all content.