TOKYO -- Clinical trials for a COVID-19 pill have kicked off across the world, as pharmaceutical companies work on a simpler and more affordable way to treat patients and help finally bring the pandemic under control.
U.S.-based Merck is working with startup Ridgeback Biotherapeutics on an oral antiviral treatment called molnupiravir. A final Phase 3 trial for the drug is currently being conducted worldwide, including in Japan, and its findings could become available as early as October.
Merck plans to seek emergency use authorization for molnupiravir in the U.S. by the end of the year, and could seek emergency use authorization in Japan a month or two afterward.
Molnupiravir was originally developed to treat the flu, but is expected to be effective against the coronavirus as well. The U.S. Department of Health and Human Services has signed a deal to purchase 1.7 million doses for $1.2 billion, and Merck is preparing to produce 10 million doses by the end of the year.
Pfizer is developing two types of antiviral candidates -- one oral and one intravenous -- based on a treatment developed for the severe acute respiratory syndrome, or SARS, outbreak that began in 2002. They are designed for patients with mild to moderate symptoms who do not require hospitalization.
Initial data from clinical trials is expected to be published between October and December, and the treatments could become availably by early next year.
Japanese drugmakers are also making inroads on oral coronavirus treatments. Japan's Shionogi began Phase 1 trials for a coronavirus pill in July. It aims to launch a large-scale clinical trial this year, and plans to bring the treatment to market by the end of 2022.
Chugai Pharmaceutical has acquired development and marketing rights in Japan for an oral antiviral being developed by parent Roche. The treatment could become available globally in 2022.
Emergency use authorization allows the U.S. to temporarily make treatments that are not approved by the Food and Drug Administration available in response to pandemics, biological terrorism and other public health emergencies. The process takes about three weeks, as opposed to the six- to 12-month screening for formal FDA approval, and authorities can withdraw the authorization should safety and efficacy concerns arise.
Japan has a similar framework, which allows emergency use of pharmaceuticals that are not yet approved in the country but are in use in the U.S., the U.K. and other countries that impose similar standards on drugs.
Japan takes about two months to screen pharmaceuticals for emergency use. If the U.S. authorizes the Merck and Pfizer treatments for emergency use by the end of the year, they could also become available in Japan by the beginning of 2022 at the latest.
Current treatments against the coronavirus include an antibody cocktail geared toward patients who have mild symptoms but are considered high-risk. But the cocktail needs to be delivered intravenously, and one round of treatment can take three to four hours.
Cost is another issue. Ronapreve, developed by Regeneron Pharmaceuticals and Roche, costs $2,100 per dose. The high price tag means its use is mostly limited to relatively rich areas with a certain standard of health care.
Oral treatments like Tamiflu could be a game changer, since they can be easily prescribed and administered to those sick at home.
Because antivirals work by stopping the virus from multiplying, they are expected to be effective against different variants. They can also be chemically formulated, which means they can be produced at existing pharmaceutical factories and for a tenth or less of the cost of antibody treatments.
The coronavirus has infected more than 230 million and killed over 4.7 million worldwide so far. Vaccination efforts are progressing in developed economies, with over 60% of those in the U.S. and Europe receiving at least one shot. Roughly 60% in Japan have received at least one dose, and over 50% have received two.
But breakthrough infections are becoming more common with the spread of the delta and other variants. Vaccine effectiveness has been reported to wane over time, making both vaccines and an oral treatment key to bringing the pandemic under control.