As I’m sure everyone is aware, vaccine rollout has been slower than we’d like. This is largely because the firs two (and so far, only) vaccines in general use, the Moderna and Pfizer mRNA-based vaccines, are both very logistically difficult: They can only be made in extremely specialized facilities, they both require super-low temperatures for storage, and they need two doses, weeks apart.
A third vaccine, from Johnson and Johnson, is expected to get the thumbs up soon, which should ease all of these problems, as it’s easier to make, requires only ordinary refrigeration, and is a single dose.
But a complication occurs to me: None of these vaccines has full FDA approval. They’re all currently under what’s called an Emergency Use Authorization. And one of the requirements for an EUA is that there be no other, approved, treatment for the same purpose.
Well, as the vaccines continue to be used, and data is collected about them, eventually they’ll get full approval. And most likely, this will happen first with the mRNA vaccines. But when that happens, won’t that end the EUA for the other vaccines? And mightn’t that cause logistical problems to spring up again after they were thought solved?
The Secretary of Health and Human Services (HHS) has a wide latitude in issuing and Emergency Use Authorization (EUA). Here is the FDA.gov summary page for EUA issuance:
Note that under III. EMERGENCY USE AUTHORIZATIONS, B. EUA MEDICAL PRODUCTS, 1. Criteria for Issuance, d. No Alternatives
For FDA to issue an EUA, there must be no adequate, approved, and available alternative to the candidate product for diagnosing, preventing, or treating the disease or condition. A potential alternative product may be considered “unavailable” if there are insufficient supplies of the approved alternative to fully meet the emergency need.A potential alternative product may be considered “inadequate” if, for example, there are contraindicating data for special circumstances or populations (e.g., children, immunocompromised individuals, or individuals with a drug allergy), if a dosage form of an approved product is inappropriate for use in a special population (e.g., a tablet for individuals who cannot swallow pills), or if the agent is or may be resistant to approved and available alternative products.
So, another vaccine candidate that can be produced more easily and cheaper than the Johnson & Johnson vaccine sufficient to satisfy demand, one targeted specifically at older people or children, or of course one that has a better demonstrated efficacy at treating novel variants or a new strain could all potentially fall under the criteria for being acceptable for an EUA.
Of course, it would be better for vaccines to be fully authorized for long term use instead of a constant end-run of EUA issuance. EUAs are really intended for contingencies involving chemical, biological, radiological, and nuclear (CBRN) agents in a mass casualty attack, not as a pre-approval step in the normal regulatory process, and are being used in this particular case both because of the need for and unprecedented rapid availability of vaccines.
Arguably, the FDA process for drug approvals needs to be modernized to reflect the faster pace of development of gene-targeted treatments like mRNA and CRISPR-Cas9 gene editing technologies, both to allow these technologies to enter human trials quicker and to assure that potential safety issues are fully addressed. Currently a lot of effort in drug development goes into animal trials of often questionable utility in both demonstrating safety and reliability, and a “Manhattan Project”-like effort really needs to be done to develop computer models for drug safety and efficacy testing:
OK, it sounds like the summaries I read were a bit oversimplified, then. If insufficient supplies is enough to be considered “unavailable”, then we can keep on using all of the vaccines, and the scenario I envisioned wouldn’t come up.
There was a stumble at the start of the American rollout that added 2 days upfront, because the FDA has regulated a 2 day stop on delivery. That’s not long in terms of development, but it’s indicative of a system where timely delivery is not a goal.