Vaccine hesitancy could slow the development of herd immunity for COVID-19 in the U.S., but there could be other ways to help reach it.
Testifying at a Senate Health, Education, Labor and Pensions (HELP) Committee hearing Sept. 9, Surgeon General Jerome Adams said the numbers needed for herd immunity vary from expert to expert, but it ranges from 60% to 80% of the population.
“Can we do that?” Sen. Elizabeth Warren (D-Mass.) asked. She noted that in the last influenza season for which data are available, fewer than 50% of adults in the U.S. got the flu vaccine. The numbers would be worse for COVID-19, she said, referencing a recent CBS poll that showed only 21% of Americans would be willing to get a SARS-CoV-2 vaccine as soon as possible. That compares with 32% in July.
However, the same poll showed 58% said they would consider it, but would wait to see what happens. That number was up from 51% in July.
The Kaiser Family Foundation framed the question differently in a poll it released Sept. 10, asking whether people would get a vaccine released before the November election. While 81% of those polled said they didn’t expect a vaccine would be approved by then, 42% said if one were available before the election, they would want to get vaccinated.
Regardless of the numbers, both polls show the challenge in quickly reaching herd immunity through vaccines. Initial supplies of the vaccines also will be a factor. In its draft vaccine allocation framework, the National Academies of Sciences, Engineering and Medicine said those supplies would be tightly constrained at first – perhaps enough to vaccinate just 3% to 5% of the U.S. population.
Fortunately, vaccines aren’t the only measure for developing immunity, Sen. Bill Cassidy (R-La.) reminded the HELP Committee, adding that the millions of people in the U.S. who have been infected likely have natural immunity now.
Cassidy cited a survey suggesting that at least 20% of New Yorkers already have been exposed to the coronavirus. Since reinfection seems to be rare, he said it would be helpful to figure out who has natural immunities because of exposure to the virus. That information could winnow down the number of people needing a vaccine, if there were up-to-date immunization registries that could be shared among the states, Cassidy said.
Adams cautioned, “This virus has fooled us many times and we still don’t know what we don’t know” in terms of COVID-19 reinfection.
But that would be true of vaccines, as well, Cassidy said. He also noted that the development of monoclonal antibodies as a preventive measure could help relieve the pressure on vaccines to build herd immunity.
Vaccine distribution plan still a work in progress
As the possibility of a COVID-19 vaccine comes closer to reality in the U.S., several lawmakers are pushing the Trump administration for answers on how it intends to distribute a vaccine, which is expected to be limited in supply when it first becomes available.
Speaking at a Senate Health, Education, Labor and Pensions Committee hearing Sept. 9, Sen. Patty Murray (D-Wash.) called for a comprehensive national vaccines plan that ensures a vaccine is distributed fairly and in a way that addresses barriers to access. She said the nation can’t afford a repeat of the problems encountered with distributing tests and supplies in the early weeks of the pandemic.
HELP Chair Lamar Alexander (R-Tenn.) said the CDC is working on a plan to distribute vaccines as soon as they’re authorized or approved, prioritizing vaccines for health care workers and vulnerable populations.
He assured his colleagues that the CDC’s plan would be a fair system informed by nonpartisan health experts from the National Academies of Sciences, Engineering, and Medicine and the Advisory Committee on Immunization Practices.
After it weighs all the public comment about the draft vaccine allocation framework it released recently, the National Academies will finalize its recommendations. The time involved in federal agencies implementing those recommendations into a distribution system has raised concerns for states and health care systems, as it wouldn’t give them much time to prepare, especially if the vaccines require special storage conditions.
As it is, many systems already have bought additional storage units for extra influenza vaccines in expectation of a greater demand for flu shots this year, Sen. Susan Collins (R-Maine) said. Having to purchase subzero units, which would be required should Pfizer Inc.’s vaccine be approved, could be a challenge in areas hard hit economically by the pandemic, she added.
Federal agencies are working intensely to address the distribution issues, NIH Director Francis Collins told the committee. But figuring out the logistics is tough when officials don’t know which vaccines will be approved, as the six candidates under development have different storage requirements, he said.
Adcoms considering impact of Oxycontin ADF
Has the abuse-deterrent formulation (ADF) of Oxycontin (oxycodone hydrochloride) extended-release tablets made much of a difference in terms of the abuse and misuse of the Purdue Pharma LP opioid pain drug?
That’s what the FDA’s Drug Safety and Risk Management Advisory Committee and its Anesthetic and Analgesic Drug Products Advisory Committee are considering Sept. 10 and 11 as they review the results of four required postmarketing studies.
According to the FDA, the totality of the evidence from the studies and published literature is “fairly compelling” that the reformulation has reduced abuse of Oxycontin through snorting and injection. But the agency’s review team questioned how meaningful that reduction was, saying the effect couldn’t be easily quantified and likely varies across populations.
The FDA reviewers also said it was unclear if the reformulation reduced overdoses or had a net public health benefit.
While the intent behind ADFs is well-meaning, there’s been a lot of debate in previous adcoms on what makes a formulation abuse-deterrent. That lack of clarity seems to have played out in the market. As of last year, ADFs made up only about 2% of the opioid pain market, according to Cortellis, and several approved opioid ADFs are no longer being marketed.
House committee extends PRV program
In a marathon session Sept. 9, the U.S. House Energy and Commerce Committee passed 26 health bills, including an amended version of H.R. 4439, the Creating Hope Reauthorization Act, which would extend the priority review voucher (PRV) program for four years for drugs developed to treat rare pediatric diseases.
The original bipartisan bill would have made the program permanent. However, some committee members, including Chair Frank Pallone (D-N.J.), were skeptical that the transferrable vouchers truly incentivize the development of new drugs as intended.
The other health-related bills sent to the full House would expand access to mental health services, address the opioid epidemic, improve Medicare enrollment, streamline public health data sharing for tribes and facilitate access to marijuana for medical research.