The US Department of Health and Human Services (HHS), through its Biomedical Advanced Research and Development Authority (BARDA), today announced that it has awarded Moderna $176 million to develop a prepandemic vaccine against H5 avian influenza.
In its announcement, HHS said the award helps bolster the nation's pandemic flu vaccine capacity, which currently relies on an older traditional vaccine platform. Moderna will leverage its domestic large-scale commercial mRNA vaccine manufacturing platforms and ongoing development of mRNA-based seasonal flu vaccines.
The award comes as officials confirm more H5N1 avian flu in US cattle and poultry.
Phase 3 trials could begin next year
Dawn O'Connell, JD, assistant secretary for preparedness and response at HHS, said the $176 million represents the base award and the agreement contains other options that allow the government to quickly pivot funding to other mRNA vaccines when new flu strains or other disease threats emerge. She said the H5 vaccine is in clinical development and that phase 3 trials could begin in 2025.
The award also includes an option for large-scale production and pandemic response. At today's briefing, Robert Johnson, PhD, director of medical countermeasures at BARDA, said it's too early to project production capacity. He said the number will depend on dosing information, which should be available later this year.
Moderna said in a statement today that in 2023 it launched a phase 1/2 clinical trial of an investigational pandemic flu vaccine in healthy adults, which included candidates against H5 and H7 viruses, and results are expected this year.
Meanwhile, fill-and-finish activity continues on vaccine from bulk stocks of candidate cell-based adjuvanted H5 vaccine made by CSL Seqirus, and O'Connell said the first of 4.8 million doses will be available in the middle of July, with production continuing through August. This is faster than the government had anticipated.
Officials weigh early vaccine use for high-risk groups
As vaccine production and planning continues, federal officials are in ongoing discussions about how to best protect farm workers and others exposed to cattle.
Nirav Shah, MD, JD, principal deputy director for the Centers for Disease Control and Prevention (CDC), said if the main goal is to prevent transmission, using antiviral drugs for patients and their contacts may achieve the goal faster than a vaccine. He said health officials are weighing the risks and benefits, as well as whether people exposed to infected cattle will accept the vaccine.
So far, more than 780 people exposed to cattle have been monitored, and at least 53 with flulike illness symptoms have been tested for H5, he said. At this point, the number of confirmed human infections linked to the virus in dairy cows stands at three.
Shah said the nation has an ample supply of H5 tests, with 750,000 available and 1.2 million coming online over the next several months.
More detections in cattle and poultry
The official number of confirmed cases of H5N1 in dairy herds remains at 137 in 12 states, according to the US Department of Agriculture (USDA) Animal and Plant Health Inspection Service. But individual affected states have announced a few more detections, including Minnesota, with another infected herd in Benton County, located in the state's central region.
Regarding poultry, USDA APHIS added confirmations of four more H5N1 outbreaks in flocks in two states, Colorado and Minnesota, both of which are also battling the virus in dairy cattle. Colorado's two outbreaks involve backyard flocks in Morgan and Larimer counties, and Minnesota's two outbreaks involve commercial turkey farms in Otter Tail and Swift counties.
At today's media briefing, federal officials were asked about recent reports of wastewater detections of H5 avian flu virus in San Francisco. Tracking from WastewaterSCAN has detected positive findings that aligned with outbreaks in cattle in six states, except for some detections in California.
Shah said San Franciso isn't known for dairy industries, and one hypothesis is a potential link to live-bird markets. Since 2022, USDA APHIS has reported sporadic highly pathogenic avian flu detections at live-bird markets in five states, with the most recent one reported from San Francisco in May of this year.
