Moderna's candidate COVID-19 vaccine looks to protect 94.5% of those who get it, trial shows. 'This makes me giddy,' one doctor says.

A second COVID-19 candidate vaccine looks to be even more effective than the first, with both protecting more than 90% of those who get the shots.

Moderna, a Cambridge, Massachusetts-based biotechnology company, announced early Monday that its candidate vaccine, mRNA-1273, developed in collaboration with the U.S. government, appears to be 94.5% effective against the disease.

Earlier this month, Pfizer and its German partner BioNTech, announced early effectiveness data, showing their vaccine, called BNT162b2, had protected more than 90% of those who received it.

Both results are preliminary, with final results expected in as soon as a few weeks.

"This is better than Christmas," said Dr. Monica Gandhi, professor of medicine at the University of California, San Francisco. "The interim results of these two exciting mRNA vaccine candidates over the past week are encouraging, hopeful and move us massively forward to getting out of this pandemic!"

A colleague was equally thrilled.

"There's part of me that tries to hear this as a dispassionate physician, but as a human being, this makes me giddy," said Dr. Robert Wachter, chair of the Department of Medicine at UCSF. "You can really see the light at the end of this tunnel. It's unbelievable."