Trump officials debating cutting Moderna dose in half to speed up COVID-19 vaccination

Trump officials debating cutting Moderna dose in half to speed up COVID-19 vaccination
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Trump administration officials are in discussions with Moderna about speeding up the coronavirus vaccination process by only giving people half the recommended dose of the company's vaccine, a top adviser said Sunday.

Moncel Slaoui, the chief science adviser for Operation Warp Speed, said there is evidence that giving people between the ages of 18 and 55 two half-doses "induces identical immune response" to the normal 100 microgram dose.

During an interview with Margaret Brennan on CBS's "Face the Nation," Slaoui said the strategy "means exactly achieving the objective of immunizing double the number of people with the doses we have." 


But Slaoui has also strongly advocated against the idea that people need only one shot instead of the current two-dose regimen, so it's not clear how giving people two half-doses would be different. 

Slaoui's comments come as the U.S. vaccination program has crawled out of the gate. Distribution of vaccines has been slower than expected, and actual vaccinations have been even slower. 

The administration did not come close to its goal of vaccinating 20 million people by the end of 2020. Only about 4 million Americans received the first of two doses, and just over 13 million doses have been delivered, according to the Centers for Disease Control and Prevention.

Logistical problems have plagued the Trump administration’s distribution efforts, with much of the crucial “last mile” of work falling to underfunded local health departments. 

States are struggling to administer the doses they already have, leading many experts to question a strategy that effectively doubles the dose availability, but does not provide additional help to the jurisdictions.

Slaoui told Brennan that he and others in the administration assumed that when states ordered specific numbers of doses, they had distribution plans in place.


"Our assumption has been that there is a plan in place to immunize. We stand by here to help any specific request. We will do the best we can, as we have done over the last eight months, to make these vaccines, indeed, make it into the arms of people," Slaoui said.

Under the current federal plan, the administration's Operation Warp Speed only delivers half the number of needed doses to states every week. The other half remain in a warehouse, held back to ensure there is enough supply for a second dose.

Given the inefficient rollout, health experts and federal officials have been looking for ways to speed up the process. 

One possibility, recently adopted in the U.K., is to prioritize giving everyone a first dose, delaying a second dose by as long as three months.

Slaoui said he doesn't see that happening in the U.S., and questioned the science behind the delay.

Both Moderna and Pfizer were authorized in a two-dose form, and Slaoui said trials show the second dose gives an immune response 10 times higher than the first dose

"We have no data after one dose," Slaoui said. Delaying the vaccination schedule "without any data I think would not be responsible," he said.