What do we know about rationing doses of the COVID-19 vaccines?
What do we know about rationing doses of the COVID-19 vaccines?
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Scientists and public health practitioners are considering vaccination tactics that differ from those that the FDA and other country’s health regulatory bodies approved. The tactics being considered are primarily halving doses of vaccines and delaying second doses to get first doses to more individuals, but also include reducing the number of doses and mixing and matching doses. Health officials in the UK have already decided to delay second doses of two vaccines, one made by AstraZeneca and one made by Pfizer and BioNTech, and to mix and match the two vaccines for the two doses under limited circumstances. This decision has received mixed responses from scientists and public health practitioners, many of whom are concerned about the lack of data, particularly with regards to a mix-and-match approach. Moncef Slaoui, scientific adviser of Operation Warp Speed, the U.S. effort to accelerate COVID-19 vaccine development and distribution, proposed distributing half-doses of the Moderna vaccine (50 micrograms versus 100 micrograms) on Sunday, December 3, as an approach to increasing the amount of vaccinations available. In support of this approach, Slaoui cited that the Moderna study compared the immune response in people given 50 micrograms against those given 100 micrograms of the vaccine, and that the doses yielded identical responses. However, the trials primarily focused on studying 25 micrograms and 100 micrograms, and the U.S. Food and Drug Administration (FDA) which would have to approve the shift in vaccine distribution stated that this data was insufficient to justify a shift to halving doses or other proposed regimen changes designed to stretch out doses at this point, as of January 6, 2020. The data on the 50 microgram doses comes from the Phase 2 study by Moderna, that was tested on hundreds of people versus tens of thousands tested with the 100 micrograms in Phase 3, and was designed to test only for immune response and not efficacy of the vaccine. On the evening of late Monday, January 4, 2021, the U.S. FDA critiqued the idea of halving the doses of the Moderna vaccine, saying that the idea was “premature and not rooted solidly in the available science.” Studies are underway to determine whether doses of the Moderna COVID-19 vaccine can be halved to 50 micrograms in order to double the supply of the vaccination doses in the U.S., according to the National Institutes of Health and Moderna.
Scientists and public health practitioners are considering vaccination tactics that differ from those that the FDA and other country’s health regulatory bodies approved. The tactics being considered are primarily halving doses of vaccines and delaying second doses to get first doses to more individuals, but also include reducing the number of doses and mixing and matching doses. Health officials in the UK have already decided to delay second doses of two vaccines, one made by AstraZeneca and one made by Pfizer and BioNTech, and to mix and match the two vaccines for the two doses under limited circumstances. This decision has received mixed responses from scientists and public health practitioners, many of whom are concerned about the lack of data, particularly with regards to a mix-and-match approach. Moncef Slaoui, scientific adviser of Operation Warp Speed, the U.S. effort to accelerate COVID-19 vaccine development and distribution, proposed distributing half-doses of the Moderna vaccine (50 micrograms versus 100 micrograms) on Sunday, December 3, as an approach to increasing the amount of vaccinations available. In support of this approach, Slaoui cited that the Moderna study compared the immune response in people given 50 micrograms against those given 100 micrograms of the vaccine, and that the doses yielded identical responses. However, the trials primarily focused on studying 25 micrograms and 100 micrograms, and the U.S. Food and Drug Administration (FDA) which would have to approve the shift in vaccine distribution stated that this data was insufficient to justify a shift to halving doses or other proposed regimen changes designed to stretch out doses at this point, as of January 6, 2020. The data on the 50 microgram doses comes from the Phase 2 study by Moderna, that was tested on hundreds of people versus tens of thousands tested with the 100 micrograms in Phase 3, and was designed to test only for immune response and not efficacy of the vaccine. On the evening of late Monday, January 4, 2021, the U.S. FDA critiqued the idea of halving the doses of the Moderna vaccine, saying that the idea was “premature and not rooted solidly in the available science.” Studies are underway to determine whether doses of the Moderna COVID-19 vaccine can be halved to 50 micrograms in order to double the supply of the vaccination doses in the U.S., according to the National Institutes of Health and Moderna.
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What our experts say
Scientists and public health practitioners are considering vaccination tactics that differ from those that the FDA and other country’s health regulatory bodies approved. The tactics being considered are primarily halving doses of vaccines and delaying second doses to get first doses to more individuals, but also include reducing the number of doses and mixing and matching doses.
Health officials in the UK have already decided to delay second doses of two vaccines, one made by AstraZeneca and one made by Pfizer and BioNTech, and to mix and match the two vaccines for the two doses under limited circumstances. This decision has received mixed responses from scientists and public health practitioners, many of whom are concerned about the lack of data, particularly with regards to a mix-and-match approach.
Moncef Slaoui, scientific adviser of Operation Warp Speed, the U.S. effort to accelerate COVID-19 vaccine development and distribution, proposed distributing half-doses of the Moderna vaccine (50 micrograms versus 100 micrograms) on Sunday, December 3, as an approach to increasing the amount of vaccinations available. In support of this approach, Slaoui cited that the Moderna study compared the immune response in people given 50 micrograms against those given 100 micrograms of the vaccine, and that the doses yielded identical responses.
However, the trials primarily focused on studying 25 micrograms and 100 micrograms, and the U.S. Food and Drug Administration (FDA) which would have to approve the shift in vaccine distribution stated that this data was insufficient to justify a shift to halving doses or other proposed regimen changes designed to stretch out doses at this point, as of January 6, 2020. The data on the 50 microgram doses comes from the Phase 2 study by Moderna, that was tested on hundreds of people versus tens of thousands tested with the 100 micrograms in Phase 3, and was designed to test only for immune response and not efficacy of the vaccine.
On the evening of late Monday, January 4, 2021, the U.S. FDA critiqued the idea of halving the doses of the Moderna vaccine, saying that the idea was “premature and not rooted solidly in the available science.” Studies are underway to determine whether doses of the Moderna COVID-19 vaccine can be halved to 50 micrograms in order to double the supply of the vaccination doses in the U.S., according to the National Institutes of Health and Moderna.
Scientists and public health practitioners are considering vaccination tactics that differ from those that the FDA and other country’s health regulatory bodies approved. The tactics being considered are primarily halving doses of vaccines and delaying second doses to get first doses to more individuals, but also include reducing the number of doses and mixing and matching doses.
Health officials in the UK have already decided to delay second doses of two vaccines, one made by AstraZeneca and one made by Pfizer and BioNTech, and to mix and match the two vaccines for the two doses under limited circumstances. This decision has received mixed responses from scientists and public health practitioners, many of whom are concerned about the lack of data, particularly with regards to a mix-and-match approach.
Moncef Slaoui, scientific adviser of Operation Warp Speed, the U.S. effort to accelerate COVID-19 vaccine development and distribution, proposed distributing half-doses of the Moderna vaccine (50 micrograms versus 100 micrograms) on Sunday, December 3, as an approach to increasing the amount of vaccinations available. In support of this approach, Slaoui cited that the Moderna study compared the immune response in people given 50 micrograms against those given 100 micrograms of the vaccine, and that the doses yielded identical responses.
However, the trials primarily focused on studying 25 micrograms and 100 micrograms, and the U.S. Food and Drug Administration (FDA) which would have to approve the shift in vaccine distribution stated that this data was insufficient to justify a shift to halving doses or other proposed regimen changes designed to stretch out doses at this point, as of January 6, 2020. The data on the 50 microgram doses comes from the Phase 2 study by Moderna, that was tested on hundreds of people versus tens of thousands tested with the 100 micrograms in Phase 3, and was designed to test only for immune response and not efficacy of the vaccine.
On the evening of late Monday, January 4, 2021, the U.S. FDA critiqued the idea of halving the doses of the Moderna vaccine, saying that the idea was “premature and not rooted solidly in the available science.” Studies are underway to determine whether doses of the Moderna COVID-19 vaccine can be halved to 50 micrograms in order to double the supply of the vaccination doses in the U.S., according to the National Institutes of Health and Moderna.
Context and background
This debate is ongoing as countries rush to vaccinate their populations against COVID-19, which continues to surge globally. Some vaccination distribution is moving more slowly than anticipated. In the U.S, for example, just 2.6 million individuals were vaccinated by December 31, 2020 compared to the goal of 20 million by the end of 2020.
Public health practitioners are concerned about changing the vaccination practices without sufficient data, and jeopardizing safety or efficacy of the vaccines. In addition, an increased amount of doses due to halving doses, or increasing the amount of time between doses to get the first doses to more individuals, doesn’t necessarily equal increased distribution. A third concern is that altering the distribution approach might make populations more hesitant of receiving the vaccine.
This debate is ongoing as countries rush to vaccinate their populations against COVID-19, which continues to surge globally. Some vaccination distribution is moving more slowly than anticipated. In the U.S, for example, just 2.6 million individuals were vaccinated by December 31, 2020 compared to the goal of 20 million by the end of 2020.
Public health practitioners are concerned about changing the vaccination practices without sufficient data, and jeopardizing safety or efficacy of the vaccines. In addition, an increased amount of doses due to halving doses, or increasing the amount of time between doses to get the first doses to more individuals, doesn’t necessarily equal increased distribution. A third concern is that altering the distribution approach might make populations more hesitant of receiving the vaccine.
Resources
- Moderna Announces Primary Efficacy Analysis in Phase 3 COVE Study for Its COVID-19 Vaccine Candidate and Filing Today with U.S. FDA for Emergency Use Authorization (Moderna)
- Moderna Announces Publication in The New England Journal of Medicine of Interim Results From Older Adult Age Cohorts in Phase 1 Study of its mRNA Vaccine Against COVID-19 (mRNA-1273) (Moderna)
- As Rollout Falters, Scientists Debate New Vaccination Tactics (NYT)
- Studies to see if Moderna COVID-19 vaccine doses can be halved may take two months (Reuters)
- The F.D.A. opposes halving Moderna vaccine doses. (NYT)
- Francis Collins says halving vaccine doses could put people at risk of 'not getting a good outcome (Washington Post)
- Race to vaccinate millions in US off to slow, messy start (AP)
- Biden plans to release nearly all available vaccine doses in an attempt to speed delivery. (NYT)
- Moderna Announces Primary Efficacy Analysis in Phase 3 COVE Study for Its COVID-19 Vaccine Candidate and Filing Today with U.S. FDA for Emergency Use Authorization (Moderna)
- Moderna Announces Publication in The New England Journal of Medicine of Interim Results From Older Adult Age Cohorts in Phase 1 Study of its mRNA Vaccine Against COVID-19 (mRNA-1273) (Moderna)
- As Rollout Falters, Scientists Debate New Vaccination Tactics (NYT)
- Studies to see if Moderna COVID-19 vaccine doses can be halved may take two months (Reuters)
- The F.D.A. opposes halving Moderna vaccine doses. (NYT)
- Francis Collins says halving vaccine doses could put people at risk of 'not getting a good outcome (Washington Post)
- Race to vaccinate millions in US off to slow, messy start (AP)
- Biden plans to release nearly all available vaccine doses in an attempt to speed delivery. (NYT)
