A pair of arthritis medicines, including Roche Holding’s Actemra, reduced mortality and shortened recovery times in intensive care for covid-19 patients in a study, opening the possibility for another treatment option for the severely ill.

Some 27% of critically ill patients who got the arthritis drugs in the study died in the hospital, compared with about 36% of those who didn’t get the drugs, an Imperial College London research team said. Patients who got the Roche drug or Kevzara, a similar medicine from Sanofi and Regeneron Pharmaceuticals Inc., were able to be released from the hospital an average of a week earlier, the study found. Released in preprint on Thursday, the results have not yet been peer reviewed.

The findings could have “immediate implications for the sickest patients with Covid-19,” Anthony Gordon, chair in anesthesia and critical care at Imperial, said in a statement. They apply to critically ill adult ICU patients who need help breathing, Gordon said.

The study also raised hopes in the U.K., which helped fund the research, that using the arthritis medicines will ease the strain as a surge of virus cases swamps its health system. The government will encourage the use of Actemra across the country immediately and is working with Roche to ensure the medicine is available to U.K. patients, the Department of Health and Social Care said in a statement.

In previous studies, Roche’s Actemra had reduced the need for patients to be ventilated and appeared to help them leave hospitals earlier. Yet, puzzlingly, the drug hadn’t appeared to help reduce deaths. The earlier studies enrolled people who were less sick, Gordon said. “A crucial difference may be that in our study, critically ill patients were enrolled within 24 hours of starting organ support,” he said.

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Called REMAP-CAP, the trial assigned patients randomly to a range of potential Covid-19 treatments. It has enrolled more than 3,900 patients, most of them in the U.K., though only a portion of those people got the arthritis treatments. Roche’s Actemra was given to 350 patients, while 45 patients got Kevzara.