The Medicines Patent Pool (MPP) has signed a voluntary licence agreement with Japanese pharmaceutical company, Shionogi, to enable generic companies to produce its COVID-19 antiviral treatment pill candidate, provided it gets regulatory approval.

The pill, ensitrelvir fumaric acid, has already shown efficacy in a phase 2/ 3 trial involving 1,821 COVID-19 patients from Japan, South Korea and Vietnam. Those who were given ensitrelvir once a day for five days recovered 24 hours faster than those who received a placebo, Shionogi announced last week.

According to the voluntary licence agreement,  the MPP will be able to grant sub-licenses to generic manufacturers to produce the pill for manufacture and supply in 117 low and middle-income countries.

“Shionogi will waive royalties on sales in all countries covered by the agreement while COVID-19 remains classified as a Public Health Emergency of International Concern by the World Health Organization (WHO),” according to a statement from the MPP.

The agreement, signed on Tuesday at a ceremony at Shionogi’s headquarters in Osaka, is pending regulatory authorisation for the pill.

Ensitrelvir is a protease inhibitor created through joint research between Hokkaido University and Shionogi. While clinical trials in Asia through the Phase 2b part of the Phase 2/3 clinical trial in patients with mild and moderate symptoms have been completed, the Phase 2b/3 part of a trial in Asian patients (mainly in Japan) with asymptomatic or mild symptoms is still in progress as it a global Phase 3 trial for SARS-CoV-2 infected patients.

“Shionogi is proud to work on such an innovative licence agreement with the Medicines Patent Pool. This licence agreement will allow people in LMICs to have rapid access to ensitrelvir, following appropriate regulatory approvals,’ said Shionogi director Takuko Sawada.

MMP executive director Charles Gore said the agreement marked the first with a Japanese company, and it “has the potential to increase the affordable options for people living in LMICs to fight COVID-19 and support our collective efforts to put an end to the pandemic and its unacceptable death toll”. 

MPP has invited expressions of interest from potential sublicensees based anywhere in the world for sublicences to manufacture and sell ensitrelvir in the licensed territory.

It is not the first connection between MPP and Shionogi, however, as dolutegravir, an HIV drug licensed from Shionogi to ViiV Healthcare, has been extensively provided to LMICs through MPP’s agreements with ViiV.

Antiviral treatments for COVID-19 are particularly important for many LMICs that have low vaccination rates.

The MPP already has voluntary licenses for the two antivirals recommended by the World Health Organization (WHO), with Merck/MSD for molnupiravir and with Pfizer for Paxlovid to help make generic versions of those antiviral drugs available in LMICs.