Some of the first clinical data for a potential coronavirus treatment showed it did not help patients with severe cases of COVID-19, the disease caused by the coronavirus pandemic.

Scientists in China enrolled 199 coronavirus patients into a study from January 18 through February 3, randomly assigning them to get either the HIV drug Kaletra plus standard of care, or just regular care.

The drug did not show benefits in keeping patients alive, reducing the amount of virus in patients, or shortening their hospital stays.

The researchers published their findings Wednesday in The New England Journal of Medicine.

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A potential coronavirus treatment has failed in a randomized clinical trial in China.

A group of Chinese researchers tested the HIV drug Kaletra in a group of patients with severe cases of COVID-19, the disease caused by the novel coronavirus. Study results were published Wednesday in The New England Journal of Medicine.

The study enrolled 199 patients, with 99 receiving Kaletra in addition to standard of care and 100 receiving just standard of care. Patients receiving the HIV drug, which is made by AbbVie, got two doses per day for two weeks.

The study was conducted at Jin Yin-Tan Hospital in Wuhan, China. Because of the emergency nature of the outbreak, the researchers wrote they did not have time to prepare a placebo for Kaletra, so doctors and patients knew which treatment they received.

Analyzing both groups after 28 days, researchers concluded the drug didn't do a better job of treating patients than the standard of care. In particular, there were no statistically significant differences that showed the drug improving mortality, reducing the detectable amount of the virus in patients, or shortening hospital stays.

"In hospitalized adult patients with severe Covid-19, no benefit was observed with [Kaletra] treatment beyond standard care," the investigators concluded. "Future trials in patients with severe illness may help to confirm or exclude the possibility of a treatment benefit."

Kaletra is one of several existing drugs that are being tested as repurposed coronavirus treatments. Other include remdesivir, an antiviral developed by Gilead Sciences, chloroquine, a genetic malaria pill, and Kevzara, an arthritis treatment made by Sanofi and Regeneron.

A 'heroic effort' with a 'disappointing' ending

In a related editorial, the journal's editor in chief Eric Rubin and deputy editor Lindsey Baden applauded the scientists for running this study under the extraordinary pressure of an epidemic.

"This was a heroic effort," Rubin and Baden wrote. "Health care workers in Hubei province have provided patient care in an overwhelming epidemic while they themselves are one of the highest risk groups for development of disease."

"Unfortunately," they added later on, "the trial results were disappointing."

In answering why Kaletra didn't work, they write that this trial focused on a "particularly challenging patient population" and the HIV drug isn't especially potent against this novel coronavirus.

Detailed results show some potential promise for Kaletra, but requires further study

About 14% of the patients receiving Kaletra also stopped the trial early because of side effects, most commonly gastrointestinal ones such as nausea, vomiting, and diarrhea.

The patient group had a median age of 58 years old and typically had started to develop symptoms 13 days before first receiving treatment. For both groups, those on Kaletra and those not taking it, it took 16 days on average to see clinical improvement.

While the study's main goal was to test to see if Kaletra could speed up the time to clinical improvement, researchers tracked a range of other metrics that may show some benefit.

Patients on Kaletra had a median time in the intensive care unit of 6 days compared to 11 days for the control group. For the slice of patients that were treated within 12 days of developing symptoms, Kaletra did appear to help them get better.