A report released yesterday by the US Government Accountability Office (GAO) says supply chain issues could interfere with a smooth rollout of a COVID-19 vaccine and that the Food and Drug Administration (FDA) should disclose scientific review of vaccine and drug efficacy and safety data when issuing emergency use authorizations (EUAs).
The report states that Operation Warp Speed, an effort of the Department of Health and Human Services, the Department of Defense, and private industry to dramatically accelerate development of COVID-19 vaccines and therapeutics, has condensed the timeline by directing more than $10 billion to vaccine manufacturers. But, it adds, the FDA needs to address public concerns that the process has been rushed, casting doubt on vaccine and drug effectiveness and safety.
Four COVID-19 vaccine candidates are undergoing phase 3 trials in the United States: mRNA vaccines by Moderna and Pfizer/BioNTech and replication-defective live-vector vaccines by Janssen and AstraZeneca. All four vaccines allow cells to generate the spike protein of SARS-CoV-2, the virus that causes COVID-19, so the body can produce antibodies against it.
Problems scaling up for mass production
The report details the challenges of scaling up mass production of COVID-19 vaccines and drugs, including needing to add new manufacturing capacity—or shift capacity from other products—because most was already in use before the pandemic.
Even when large quantities of vaccines and drugs are manufactured, they must be sealed in sterile containers in finish-fill facilities, the current scarcity of which could lead to production backlogs. Supplies of products needed for this process, including glass vials and syringes, are also limited.
The report cautions that manufacturing supply chains may struggle to keep up with demand because of coronavirus-related disruptions such as changes in worker availability, fluctuating demands for certain products, and some countries' export restrictions.
"For example, officials at one COVID-19 vaccine manufacturing facility told us that they have experienced challenges obtaining materials, including disposable reactor bags, reagents, and certain chemicals," the report states. "They also said that due to global demand, they sometimes must wait 4-12 weeks for items that before the pandemic were typically available for shipment within one week."
The transfer of knowledge of how to manufacture COVID-19 vaccines and drugs and scale up production to multiple manufacturing sites can also be complicated. "Additionally, there has been at least one instance in which the technology transfer process for a COVID-19 vaccine has been hampered by disagreements over ownership of intellectual property rights related to manufacturing technology," the report said.
And recruiting and training workers in the specialized skills they need to complete vaccine production processes can be difficult—even for experienced manufacturers. "For example, we heard from representatives at a COVID-19 vaccine manufacturing facility that filling open positions for mid- to upper management positions had been a challenge," the report said. "These positions are significant because manufacturing managers function as the technical points of contact for production questions and are responsible for managing safety, quality, and compliance with current good manufacturing practices."
The report noted that federal agencies and vaccine manufacturers are working through Operation Warp Speed to increase domestic production capacity, accelerate procurement and delivery of crucial manufacturing equipment, and work with suppliers to increase production capacity for critical materials.
Some problems with EUAs
Vaccine developers are already starting to produce COVID-19 vaccines, even as testing is still in progress, so Operation Warp Speed aims to be ready to disseminate vaccine as soon as the FDA issues an EUA for it. EUAs allow the temporary use of unapproved vaccines or therapeutics or unapproved applications for them during emergencies such as the pandemic.
However, EUAs don't guarantee that the approved products will work as intended, because they don't have to meet as high of standards for efficacy as under the usual approval mechanism. As the report points out, the FDA has revoked EUAs for drugs that later proved ineffective for the treatment of COVID-19, including chloroquine and hydroxychloroquine.
Other concerns about EUAs noted in the report are that mass availability of a vaccine or drug could curtail participation in clinical trials of other promising products and that using a drug originally approved for another indication to treat COVID-19 could create a shortage of the drug for those needing it for its original use.
Also, the public's suspicion of a vaccine available under an EUA may lead to reduced vaccine uptake.
Information for the road ahead
Releases of supporting data for EUAs have varied widely in type and amount for different audiences, the GAO notes. For example, the FDA did not release evidence for the chloroquine and hydroxychloroquine EUA until the revocation letter was released to the public.
The report urges the FDA to be uniformly candid about the data supporting EUAs of COVID-19 vaccines and drugs. "We've found that FDA has not uniformly disclosed information about its decisions on COVID-19 therapeutics," the GAO said in a blog post yesterday. "This lack of transparency could erode the public’s trust in FDA's decisions about COVID-19 vaccines or therapeutics."
Also, state and local health official representatives and healthcare providers interviewed by the GAO said they are still looking to the government for information on technological and reporting requirements for tracking vaccine inventories, the protocol for distributing vaccines to different groups and jurisdictions, recommendations for storing large amounts of vaccine that may need ultra-cold storage, and a strategic communications plan for public messaging.