HOUSTON -- COVID-19 treatment trials involving plasma are being put on hold, after top federal health officials said they need more data.
Plasma is the yellow residue you see after blood comes out. According to researchers, potential life-saving antibodies live in the plasma of a person who has recovered from COVID-19.
The idea is that if a person sick with COVID-19 is given the antibody-rich plasma, they will recover. Doctors said it's taking time to see how well this actually works.
RELATED: Coronavirus symptoms: Mysterious, scary symptoms persist long after initial COVID-19 infection
At Houston Methodist Hospital, there were 136 patients who got COVID-19 antibodies and were more likely to be alive four weeks later, compared to 251 patients who didn't get it. Doctors said the key was giving them the plasma within three days of getting to the hospital.
There are 10 trials like this one happening all over the United States, but each trial has a few hundred people.
RELATED: COVID-19 treatments like remdesivir are in high demand but limited supply, so who gets them?
Potential coronavirus plasma treatment approved by FDA now on hold