FDA Requires Lengthier COVID-19 Vaccine Safety Data for any Applications

The US Food and Drug Administration (FDA) has released new guidance for developers of coronavirus 2019 (COVID-19) vaccine candidates to follow when submitting the product for Emergency Use Authorization (EUA) approval.

Within the guidance is language stating phase 3 assessments submitted in part of the EUA application should include a median follow-up duration of at least 2 months post-vaccination regimen, in order for the FDA to assuredly determine a benefit-risk profile.

The particularities of this guidance would mean the 4 developers already into phase 3 assessment would likely not be able to provide an adequate EUA application prior to the Presidential election next month. Reports that came out last night indicated White House officials originally attempted to block this new FDA guidance because of its timeline conflicting with President Trump’s campaign statement on having a COVID-19 vaccine available by November 3.

The FDA’s resolution emphasizes the prioritization of scientific procedure over expediency and political victory, at a time when experts are stressing that assuring the public on the effectiveness and safety of vaccines is vital to eventually reaching majority immunity to the pandemic.

The FDA guidance called for developers to provide crucial safety outcomes among its submitted phase 3 data, including any adverse events, cases of severe COVID-19 disease among trial participants, and cases of COVID-19 occurring during the period when adaptive and memory immune vaccine responses would be expected to be preventive of such an event.

The agency further stated it would require the following parameters of safety outcomes in order to adequately determine a benefit-risk profile for a COVID-19 vaccine:

• An adequate rate of local and systemic solicited adverse reactions collected for the trialdefined duration of follow-up that would characterize reactogenicity in each protocol-defined age cohort participating in the study.
• All safety data collected up to the period when the database is locked for EUA request submission, as well as at least 3000 vaccine recipients followed for serious and standard adverse events of special interest for at least 1 month postregimen completion.
• A sufficient rate of severe COVID19 cases among participants to support evidenced low risk of vaccine-induced enhanced respiratory disease (ERD).

Because screening for prior SARS-CoV-2 infection is unlikely to occur prior to administration of an emergency-authorized COVID-19 vaccine, the FDA also advised developers submit vaccine safety and COVID-19 outcomes among individuals with prior, if not asymptomatic, SARS-CoV-2.

Additionally, EUA requests should include plans for active safety outcome follow-up research among individuals administered the vaccine under an EUA.

Just earlier today, Bridget Calhoun, DrPH, MMS, Associate Dean for Academic Affairs and Research, and Chair and Associate Professor at Rangos School of Health Sciences at Duquesne University, summarized the sentiments of clinicians who have stressed for months now that COVID-19 vaccine development, distribution, and monitoring remain in the boundaries of previously-set national surveillance and regulation standards.

“I hope this is not going to get policitized by any side or anyone. And I trust in our scientific colleagues that they do the right thing by looking at the data, and make those decision based only on the data and the clinical outcomes that were designed when the clinical trial was designed,” she said.

Part of the earliest demands to developing a vaccine candidate is in having the foresight toward what measures of benefit are most important at trial’s end, Calhoun said.

“And they will not be adjusted for political pressure,” she said. “Hopefully that remains the case, and safety and efficacy are the only things driving this timeline.”