Studies show that there is no benefit of COVID for prophylactic hydroxychloroquine or convalescent plasma.

Two studies published yesterday New England Journal of Medicine It was found that two once promising but largely unreliable COVID-19 treatments, hydroxychloroquine and convalescent plasma, did not prevent infection or provide clinical improvement.

“There is no compelling data”

the first SurveyAn open-label study led by researchers at Hospital Germans Trias i Pujol in Barcelona, ​​Spain, found 800 milligrams (mg) of hydroxychloroquine clusters of healthy adults exposed to high-risk, close contact with COVID-19 patients. And subsequent 6 days of 400 mg or regular care.

Of the 2,314 contacts of 672 COVID-19 patients identified between March 17 and April 28, 1,116 were assigned to receive hydroxychloroquine and 1,198 were assigned to routine treatment. I did. The results of the two groups were similar, with 5.7% of participants in the hydroxychloroquine group and 6.2% of the usual care group becoming ill within 14 days of exposure (risk ratio, 0.86).

Patients who received hydroxychloroquine were not less likely to become infected than those who received conventional treatment (18.7% vs. 17.8%). Patients in the hydroxychloroquine group had a much higher incidence of adverse events (56.1%) than those who received conventional treatment (5.9%), but no serious treatment-related side effects were reported.

Patients who received hydroxychloroquine were more likely to test positive for coronavirus antibodies (14.3%) than in the usual care group (8.7%).

Elevated coronavirus loading in both baseline and first-episode contacts was associated with an increased risk of symptomatological COVID-19, but the risk was not significantly different between the two study groups. There was also no significant difference in time to symptomatic infection, with a median hydroxychloroquine group of 4 days and a median of the usual treatment group of 5 days.

Hydroxychloroquine, an antimalarial drug, has shown antiviral activity in vitro. One of the randomized controlled trials of hydroxychloroquine for post-exposure prophylaxis was promising, but the design of the trial was later questioned. Other studies found no evidence of a preventative effect.

“Despite the promising in vitro results that have listed hydroxychloroquine as a leading candidate for COVID-19 treatment and prevention, there are no compelling data to suggest that hydroxychloroquine is effective,” the authors said. Stated.

There is no difference in clinical status and results

Secondly SurveyA double-blind randomized trial, a research team led by scientists at the Italiano de Buenos Aires Hospital in Argentina, admitted 228 patients with severe pneumonia and low oxygen levels at 12 sites receiving 500 ml of restorative plasma. Outcomes of COVID-19 patients were compared with 105 patients who received placebo.

No significant difference in clinical status was observed between the two groups on a 6-point ordinal scale at 30 days (odds ratio, 0.83). Mortality was 10.96 percent in the convalescent plasma group and 11.43 percent in the placebo group (risk difference, -0.46 percentage points).

The incidence of adverse events in the two groups was similar (4.8% in the convalescent plasma group and 1.9% in the placebo group). Anti-coronavirus antibody levels tended to be higher in the convalescent plasma group than in the control group 2 days after treatment.

Convalescent plasma collected from patient donors who have recovered from an infection has been used for over a century in the hope that the injected antibody will initiate an immune response. However, despite being commonly used as a treatment for severe COVID-19, convalescent plasma does not have supporting data from randomized controlled trials.

“In our study, patients with severe pneumonia due to COVID-19 who used convalescent plasma therapy in addition to standard treatment had a lower 30-day mortality rate compared to placebo and other clinical trials. The outcome did not improve, “the authors write. “We believe that the use of convalescent plasma as standard treatment for such patients should be reassessed.”

They added that future studies of other types of antibody therapy should focus on treatment with other patient populations or other types of formulations such as intravenous immunoglobulins or anti-coronavirus monoclonal antibodies.