New York state’s plan to deal with bird flu if it begins to spread among the population relies heavily on a vast stockpile of flu drugs. But experts worry that stockpile is missing a key tool.
New York state has only one type of antiviral flu drug, Tamiflu, which may prove less effective than expected against a pandemic strain of bird flu, some experts say. There is another antiviral that may work even if Tamiflu doesn’t: a drug called baloxavir marboxil.
And yet the state has not stockpiled a single dose in case of emergency.
“This could be an Achilles heel here,” said Dr. Sean T. Liu, an infectious diseases expert at Mount Sinai Hospital in Manhattan.
Given the uncertainty about how bird flu will evolve and which treatments might ultimately be most effective, some public health experts worry that New York is relying too heavily on a single drug when an alternative is available.
“It’s always wise, when there are unknown variables, to have more than one treatment option in your toolbox,” said Dr. Howard Zucker, a former state health commissioner who led the health department during the coronavirus pandemic and oversaw the state’s epidemic stockpile until 2021.
Some experts fear the next pandemic could come in the form of H5N1, a flu virus that has long circulated among wild birds and sometimes causes outbreaks in poultry flocks. The virus can infect people who come into contact with sick birds and has killed about half of the nearly 1,000 people who have contracted it.
The virus has not been transmitted from person to person, but it has begun to spread to mammals, which is worrisome. Late last year, it began spreading among dairy cows, infecting herds from Texas to Michigan. Public health officials have long been preparing for the possibility that it could one day transmit effectively from person to person.
In New York, health officials have stockpiled ventilators and accumulated enough Tamiflu for about 10 percent of the state’s population. The federal government and New York City also have their own stockpiles.
The government bought Tamiflu more than 15 years ago, when it was the leading antiviral against influenza. But in 2018, a promising new flu drug came onto the market: baloxavir marboxil, marketed as Xofluza.
There is no way to know how effective either drug would be against a pandemic flu strain that has not yet evolved. Tamiflu might be effective, but it might not be. The same is true for baloxavir. Some versions of the circulating H5N1 virus have mutations that make them resistant to Tamiflu, and baloxavir works differently.
When the influenza virus infects a cell, it hijacks the cell’s machinery to produce new virus particles. Tamiflu targets the viral enzyme that allows newly formed virus particles to break away from the infected cell. This limits their ability to infect new cells. Baloxavir blocks another enzyme and prevents viral replication in the host cell.
During a flu pandemic, antiviral drugs could mean the difference between life and death for those infected, especially during the first wave before a vaccine is available.
Erin Clary, a spokeswoman for the Department of Health, said baloxavir is expensive, often costing $180 at pharmacies. It’s unclear whether other states have purchased it in bulk as part of their pandemic response plans.
“Stockpiling an expensive drug that is not recommended by the CDC is fiscally irresponsible,” she said, adding that oseltamivir – the generic form of Tamiflu – is the “main recommended antiviral” for bird flu.
The CDC recommendations cited by Clary, however, are advice to doctors about what drugs and dosages to use, not instructions on how public health officials should prepare for the unknown.
Dr. Liu, of Mount Sinai Hospital, who has treated Covid-19 patients and previously worked on developing a universal flu vaccine, noted that some viruses are better treated with a cocktail of drugs, rather than just one. In interviews, several doctors said that in the event of a flu pandemic, they might want to have the option of treating patients with Tamiflu and baloxavir at the same time.
“If I were in his shoes and I got H5N1 right now and I was terribly sick, I would definitely ask for a combination of two things,” Dr. Liu said.
Baloxavir is not part of New York State’s stockpile of antiviral drugs for a variety of reasons. In the mid-2000s, as the federal government was building its own stockpile of Tamiflu, it offered to subsidize states’ efforts to do the same. New York State purchased 2,029,721 doses of Tamiflu manufactured in 2006 and 2007.
Baloxavir wasn’t approved until 2018. At the time, a committee of federal scientists recommended ordering eight million doses of baloxavir for the federal stockpile, said Dr. Rick Bright, who at the time headed the Biomedical Advanced Research and Development Authority (BARDA), a federal agency involved in disaster preparedness. There was an urgent need to “diversify” the stockpile’s drugs, Dr. Bright recalled.
But executives ignored that recommendation and opted for more Tamiflu, he said. Tamiflu’s patent had expired in 2016 and the generic form of the drug, oseltamivir, had become available and was relatively cheap.
Dr. Bright filed a lawsuit in 2020, partly over the Trump administration’s response to COVID-19 but also criticizing federal officials for their decision to forgo baloxavir. The lawsuit claims that “political connections and cronyism” played a role in the drug contracts for the federal stockpile.
The contract for the generic form of Tamiflu was awarded to a pharmaceutical company represented by a favored consultant who appeared to have a “disproportionate role” in contract decisions, according to the whistleblower’s complaint.
At the time, the consultant issued a statement “unequivocally” denying any wrongdoing and saying Dr Bright’s allegations were false.
A spokesman for the federal Strategic Preparedness and Response Administration, which oversees the stockpile, declined to comment on the specifics of Bright’s complaint, stressing that his concerns related to the previous presidential administration. The spokesman, Spencer Pretecrum, said his agency had sought to “build a diverse inventory of medical countermeasures in the Strategic National Stockpile that most effectively and broadly protect against a range of potential pathogens.”
The federal government has since added between 500,000 and 1 million doses of baloxavir to its stockpile, according to Pretecrum, the agency spokesman. He added that future orders were planned.
But in New York, the Health Department has shown little interest in adding baloxavir to its stockpile.
“The department has no plans to stockpile baloxavir at this time,” said Clary, the spokeswoman.
Jay Varma, a former CDC epidemiologist who helped guide New York City’s response to COVID-19 as a city councilman, urged city and state health officials to conduct their own assessments. “I think it’s important that New York State and New York City carefully evaluate the potential need for antivirals in the event that H5N1 evolves into sustained human-to-human transmission,” he said.
The city’s stockpile is smaller, with 427,000 doses of Tamiflu and no baloxavir.
No matter how bird flu plays out, New York State may soon be forced to replenish its stockpile. After the FDA already extended the shelf life of the state’s Tamiflu doses, they are set to expire in 2026 and 2027.