The World Health Organization (WHO) has launched the new phase of its Solidarity clinical trial to assess three new drugs to treat patients hospitalised with Covid-19.

Named Solidarity PLUS, the new trial will investigate artesunate, imatinib and infliximab, which are already used to treat other diseases.

An independent expert panel chose these drugs as they exhibited the potential to lower the mortality risk in hospitalised patients with Covid-19.

Solidarity PLUS will see participation by numerous researchers at more than 600 hospitals across 52 countries, representing 16 more countries compared to the first phase Solidarity trial.

Said to be the largest worldwide partnership between WHO member states, the trial can evaluate several therapies simultaneously under one protocol.

The trial, set to enrol thousands of participants, is designed to gather data on a drug’s effect on mortality, including moderate effects.

Over the duration of the trial, new therapies can be added and ineffective therapies can be removed.

Artesunate, imatinib and infliximab are manufactured by Ipca, Novartis and Johnson & Johnson, respectively. The companies donated the drugs for use in Solidarity PLUS.

An artemisinin derivative, artesunate is used for malaria treatment while imatinib is a small molecule tyrosine kinase inhibitor meant to treat some cancers.

Meanwhile, infliximab is a tumour necrosis factor (TNF) alpha inhibitor that is indicated for the treatment of immune system-related diseases such as Crohn’s disease and rheumatoid arthritis.

Participants in the Solidarity PLUS trial will receive intravenous artesunate for seven days, oral imatinib once a day for 14 days or intravenous infliximab as a single dose.

WHO director-general Dr Tedros Adhanom Ghebreyesus said: “Finding more effective and accessible therapeutics for Covid-19 patients remains a critical need, and WHO is proud to lead this global effort.

“I would like to thank the participating governments, pharmaceutical companies, hospitals, clinicians and patients, who have come together to do this in true global solidarity.”

The first Solidarity trial tested remdesivir, hydroxychloroquine, lopinavir and interferon. These drugs demonstrated little or no effect on hospitalised Covid-19 patients, WHO noted.