Moderna's top doctor on Monday cautioned against giving patients only half doses of its COVID-19 vaccine in an attempt to innoculate more people, saying there isn't data to prove its efficacy.
Chief Medical Officer Dr. Tal Zaks said at the J.P. Morgan Healthcare Conference, which kicked off virtually on Monday, that the company is studying the question but has only preliminary findings to date. Once it has more information, he said the company will discuss the issue with regulators. Moderna's data showing the vaccine is 94% effective is based on two doses administered four weeks apart.
"On cutting the dose in half, we're advocating for following the data and the science," Zaks said. "We do not have data on efficacy for half the dose."
COVID-19 vaccination efforts have had a sluggish start, as public health officials have said they don't have the funding or leadership to quickly disseminate the shots. The federal vaccine effort, Operation Warp Speed, fell short of its target to vaccinate 20 million Americans in December, as only 6.6 million have received their first dose as of Friday.
But the delays aren't necessarily due to supply. Moderna's CEO, Stephane Bancel, said the company is "very comfortable" in its ability to deliver 600 million doses of its vaccine in fiscal 2021. He said the company has the infrastructure and people to deliver up to 1 million doses in fiscal 2021, but given it's a new manufacturing process, executives will refine their predictions as the year goes on. In fiscal 2022, Bancel said Moderna will be able to deliver 1.2 billion doses. The vaccine is now authorized for use in more than 30 countries, he said.
Moderna has advance purchase agreements with governments that would bring in $11.7 billion in revenue in fiscal 2021 if the company is able to fulfill those. Of that, it has already received $2.8 billion worth of deposits, Bancel said. He added that doesn't include option agreements with governments.
David Meline, Moderna's chief financial officer, said the advance purchase agreements actually amount to slightly less than 600 million worth of vaccines, not including option agreements.
Zaks added that Moderna's research shows its COVID vaccine should provide protection for at least one year. He added that it's difficult to study whether people can still transmit the virus after getting the vaccine, so that's still unknown. Zaks said he expects to achieve herd immunity from COVID, north of 50% of the population would need to be vaccinated. Other experts have estimated at least 70% of the U.S. population would have to be vaccinated for herd immunity, although surveys portend significant vaccine hesitancy.
As for the emerging COVID variant that's even more infectious, Zaks said Moderna is monitoring the situation and could rapidly deploy vaccines based on the new variant if necessary.