Carrie Harned examines the release of antiviral flu drugs and their limited use for

Imagine your child walking into the ER with a fever of 102.3. There is nothing truly impossible about the scenario that happened to Ian Parker in 1984. In the first crisis in modern history…

Carrie Harned examines the release of antiviral flu drugs and their limited use for

Imagine your child walking into the ER with a fever of 102.3.

There is nothing truly impossible about the scenario that happened to Ian Parker in 1984. In the first crisis in modern history of what we called an acute virology crisis — the flu season flu epidemic of that year — Parker’s 9-year-old son, Dan, was sent to the emergency room in California. The paediatrician assessed his symptoms and prescribed combination antiviral drugs, more commonly known as Tamiflu and Relenza.

After a few hours on Tamiflu, Dan’s fever vanished. He was sent home with a prescription. Within 24 hours, he suffered a subarachnoid hemorrhage, an injury that can be dangerous for children who have not been immunised and when untreated, could kill. It did. Parker followed Dan’s progress through later years of the disease.

That’s the heartbreaking but not entirely uncommon story that comes back to me in the announcement of the anticipated release of antiviral drug CC-19 — the first effective influenza antiviral drug for the common seasonal flu. This drug will be sold by an as-yet-unnamed pharmacy, expected to be placed inside a centralized pharmacy system, like store-front chemists, that will distribute it to major health providers, health care providers and public health agencies across the country.

The availability of such a drug for such a devastating disease as influenza is gratifying to all of us who care about saving lives. When it comes to antivirals for the flu, progress has been slow. “The window has closed for us,” Jennifer Harris, the director of the influenza division at the Centers for Disease Control and Prevention, told me.

At the same time, I worry about the efforts to release CC-19 for an already hot season. The release of CC-19 will come about only after extensive testing and monitoring of its use, both in the United States and overseas.

Why? Influenza viruses are unpredictable. No matter what it appears to be right now, the influenza virus can change before the spring flu season. The flu can be miserable. It can kill. It can’t be passed on person to person. But we are always at risk. And the only treatment is to get as far away from the flu as possible.

So, the question I ask myself is whether stockpiling CC-19 will reduce the risk. One answer to that is that CC-19 is not a standalone flu drug. Unlike Tamiflu and Relenza, it will not be available without the antiviral drug. (HCV-3, a pre-genomic flu therapy, is another agent that may be needed during a more severe flu season, though it is far less likely.)

Nevertheless, I am curious: How can a well-crafted, regulated release of antiviral drugs for the flu be compatible with the use of the CC-19 emergency stockpile? How can antiviral drugs be given at the same time as vaccines when there is disagreement about what parts of the body are vulnerable to the flu?

With genetic sequencing technologies available, there is no longer a shortage of places in the body where people can contract the flu. These techniques permit us to follow the virus in individuals, in animals and in the atmosphere, recording it all. Where medical research leaders fear that the race to get influenza drugs out to researchers and patients could lead to misuse, or that the drugs are unlikely to be effective against a particularly problematic strain of the flu, I am not a scientist. It’s clear to me that we need more drug testing, not less.

Harris estimates that there will be, in 2019, at least twice as many people who get the flu as in 2017, when BCG antiviral therapy was the only antiviral drug available. Is the stockpiling of CC-19 not a reasonable and proportionate response, given the potentially substantial public health effects of a flu pandemic?

Several points suggest the potential for bad decisions. When Harris tells us that it is too soon to predict the effectiveness of CC-19, she is absolutely right. The first clues about its effectiveness will be available only about two years after the drug goes on sale. That’s another way of saying we won’t know if CC-19 works until we have made that choice.

An ongoing trial in Peru has shown that CC-19 works well against pneumococcal disease, but it has not yet been shown to work against influenza. (Like so many other drug development problems, the designs for that trial, the trials that will determine if CC-19 is effective against influenza and against other diseases in person, are not ready for publication just yet.)

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