Merck’s experimental covid-19 treatment pill, molnupiravir, was approved by British regulators Thursday. (Merck & Co Inc via Reuters)
In the battle against covid-19, injected vaccines have been a game-changer in many countries. But while existing vaccines have stemmed a tide of cases in many high-income countries, massive disparities in supply have left many other countries without. Even when doses have arrived in these nations, there have been issues with distributing them before they reach their expiration date.
On Thursday, a different front opened up in the battle against covid-19 — one that was notable for revolving around pills, rather than jabs. Regulators in Britain granted approval to the experimental drug molnupiravir from U.S. pharmaceutical giant Merck, marking the first time the promising pill-based treatment for covid-19 had been authorized anywhere in the world.
It’s important to note that, unlike vaccines, molnupiravir is designed to treat people already infected with covid-19, not to prevent them from getting it. According to Merck, the pill reduced hospitalizations and deaths by nearly half among higher-risk adult coronavirus patients who had been diagnosed with mild to moderate illness. But it does not replace the need for vaccinations.
Still, as my colleagues Ellen Francis and Claire Parker write, many experts believe that “if widely authorized, the medicine could have huge potential to help fight the coronavirus pandemic: Pills are easier to take, manufacture and store, making them particularly useful in lower- to middle-income countries with weaker infrastructure and limited vaccine supplies.”
They’re likely to prove more popular among patients across the world than other available treatments; another covid-19 treatment already in use in the United States, monoclonal antibodies, requires relatively complex and often expensive procedures of injected infusions. Public health experts and advocacy organizations hope that other countries, including the United States, will soon approve molnupiravir.
The benefits of a pill over a jab could be even greater for a coronavirus vaccine. So far, all of the vaccines in widespread use require an injection. Most recommend an intramuscular injection, typically in the upper arm, to facilitate the fast spread of the vaccine, as is common with vaccines developed for many other illnesses.
Some experts have suggested that fear of needles may be an underrecognized factor among those who decline coronavirus vaccines. “About one in four adults and two out of three children have some fear of needles, and adults may find their fears too shameful to share,” C. Meghan McMurtry, an associate professor of psychology at the University of Guelph, in Ontario, wrote for the New York Times earlier this year.
But vaccines can be administered orally. There are oral vaccines for polio, cholera, and rotavirus, according to GAVI, a public-private global health alliance focused on vaccines. The viruses and bacteria that cause these illnesses commonly infect the gut, making an oral vaccination particularly useful. Covid-19 is largely a respiratory disease and in general, many vaccine formulas cannot survive the harsh environments of the gut.
But despite these difficulties, some companies have pursued oral versions of coronavirus vaccines.
Jerusalem-based company Oramed announced last week that it had won approval from the South African government to run an initial clinical trial for its orally delivered vaccine candidate, which uses specially designed capsules. MigVax, another Israeli-founded company, has received funding from the Norway-based Coalition of Epidemic Preparedness Innovations (CEPI) for its own oral vaccine tablet, the company announced Thursday.
A recent report from the World Health Organization said there were four other oral vaccine candidates in clinical development. A further eight candidates are designed to be taken intranasally; some researchers hope that vaccines administered as nasal sprays could not only be easier to take but also more effective.
Pills are an attractive option during the pandemic for a variety of reasons. In wealthy countries, even those who refuse to take injected vaccines due to concerns about their safety have often turned to pills like ivermectin, a medicine used to kill parasites in animals and humans that is unproven at fighting covid-19.
Research from the University of Toronto in 2012 found that in a large sample of parents and their children in the city, the number of people willing to take a flu vaccine or give one to their child increased by 10 percent if the vaccine could be administered without pain. If this holds true in communities resistant to getting vaccinated against the coronavirus, these other forms of vaccines could make a significant difference.
But where a covid pill — whether a treatment like molnupiravir or a vaccine — could be most useful is in the developing world. Most pills can be transported and stored easily. Training a medical worker on how to use them is simple, and in many cases, the patient may be able to take them at home without much guidance or the need for basic but limited supplies like syringes.
If they are used widely in developing countries, pills could diminish strain on health-care systems, which often leads to excess deaths, and limit the demand for items like ventilators that are in limited supply.
William Fischer, pulmonary and critical care physician and professor at the University of North Carolina at Chapel Hill who was one of the lead researchers during the Phase 2 clinical trial of molnupiravir, told my colleague Claire Parker that the potential for broader access was one of the key things that excited him about the drug.
“One of the biggest problems with our entire outbreak response strategy — vaccinations and therapeutics — has been one of access. And I think the logistical constraints with the vaccine and with the monoclonal antibodies have really created an inequity in access,” he said. “An oral therapy is exciting particularly because it can overcome those logistical constraints and ensure equal access to treatment and prevention.”
As we wrote last week, Merck has also become the first manufacturer of a covid-19 drug to reach an agreement with a nonprofit to share its license with manufacturers in low- and middle-income countries, potentially expanding use of the drug to millions of people and lowering the price of the treatment through generic versions.
Pills alone are unlikely to end the pandemic. Even if they prove effective, orally administered coronavirus vaccines are likely far away from mass production.
Even in Britain, molnupiravir will take some time to roll out to would-be patients: The BBC reports that an initial order of 480,000 courses of treatment will begin arriving in late November, with the possibility of wider use after a national study on vaccinated and unvaccinated patients.
Molnupiravir may be an easy treatment compared with others for covid-19, but it has its limitations, too. It is recommended that users take it within the first five days of the onset of symptoms. That is a tight time frame, especially in countries that have limited supplies of coronavirus tests.
And though Merck won some praise for the decision to partner with the nonprofit Medicines Patent Pool, many experts have argued that the deal was largely restricted to 105 countries and that the U.S. company would struggle to produce enough doses where generic sales were limited.
But even if pill-based treatments like molnupiravir won’t end the pandemic on their own, they are yet another valuable tool in the battle against it.