Researchers leading the RECOVERY clinical trial in the UK on Monday announced that for patients hospitalised with Covid-19 and not on a ventilator, lopinavir-ritonavir, the antiviral treatment commonly used to treat HIV, is not an effective treatment. Announcing results of the lopinavir-ritonavir arm of the trial, researchers from Oxford University said in a statement that the data “rule out any meaningful mortality benefit of lopinavir-ritonavir” in hospitalised Covid-19 patients. The researchers, however, also underlined that they “were unable to study a large number of patients on invasive mechanical ventilation because of difficulty administering the drug to patients on ventilators”. “As such, we cannot make conclusions about the effectiveness in mechanically ventilated patients. Full results will be made available as soon as possible,” the researchers said. The anti-retroviral drug lopinavir is a protease inhibitor, the class of drugs approved for the treatment of HIV; lopinavir is formulated in combination with another protease inhibitor ritonavir, to increase the half-life of lopinavir, which is the duration of action of a drug. In the trial, a total of 1,596 patients were randomised to lopinavir-ritonavir and compared with 3,376 patients randomised to usual care alone; of these patients, 4 per cent required invasive mechanical ventilation when they entered the trial, 70 per cent required oxygen alone, and 26 per cent did not require any respiratory intervention. “There was no significant difference in the primary endpoint of 28-day mortality and the results were consistent in different subgroups of patients. There was also no evidence of beneficial effects on the risk of progression to mechanical ventilation or length of hospital stay,” the researchers said. Peter Horby, Professor of Emerging Infectious Diseases and Global Health in the Nuffield Department of Medicine, University of Oxford, and Chief Investigator of the trial, said, “Today we release the third set of results from the RECOVERY trial. These preliminary results show that for patients hospitalised with Covid-19 and not on a ventilator, lopinavir-ritonavir is not an effective treatment. In 100 days, the RECOVERY trial has provided results enabling change in global practice three times. This extraordinary national effort has shown that two drugs used to treat hospitalised Covid patients throughout the world, hydroxychloroquine and lopinavir-ritonavir, do not improve survival, whilst one drug that was not recommended, dexamethasone, saves lives.”
