Science & Technology
PLACID Trials
- 27 Oct 2020
- 5 min read
Why in News
Recently, the PLACID Trial, a multicentre randomized controlled trial, has shown that the use of convalescent plasma (CP) as a therapeutic for Covid-19 patients showed no positive effects and did not improve the outcome of the patients.
- The randomised controlled trial (RCT) is a trial in which subjects are randomly assigned to one of two groups: one (the experimental group) receiving the intervention that is being tested, and the other (the comparison group or control) receiving an alternative (conventional) treatment.
Key Points
- Convalescent Plasma Therapy:
- Convalescent Plasma, extracted from the blood of patients recovering from an infection, is a source of antibodies against the infection.
- The therapy uses blood from people who have recovered from an illness to help others recover.
- Blood donated by people who have recovered from Covid-19 has antibodies to the virus that causes it. The donated blood is processed to remove blood cells, leaving behind liquid (plasma) and antibodies. These can be given to people with Covid-19 to boost their ability to fight the virus.
- The plasma donor would have to be a documented case of Covid-19 and healthy for 28 days since the last symptoms.
- PLACID Trial:
- It was conducted by the Indian Council of Medical Research (ICMR) and its aim was to investigate CPT’s effectiveness for the treatment of Covid-19.
- It is the first and largest randomised control trial to be completed in the world.
- Findings:
- The trial results indicate that there was no difference in the 28-day mortality (estimates of deaths in the 28 days after entering the hospital for a specific condition) or progression of Covid-19 from moderate to severe in patients treated with CP along with basic standard care compared to basic standard care alone.
- While the use of CP seemed to improve the resolution of shortness of breath and fatigue in patients with moderate Covid-19, this did not translate into a reduction in 28-day mortality or progression to severe disease.
- Impact of the Findings:
- The ICMR is now considering removing the option of CPT from the national guidelines.
- CPT as a treatment for Covid-19 in India has led to questionable practices such as calls for donors on social media, and the sale of convalescent plasma on the black market.
- Although CP is a safe form of treatment when transfused in accordance with the regulations, it involves resource-intensive processes such as plasmapheresis (separating plasma from the blood cells), plasma storage, and measurement of neutralising antibodies and a limited number of institutes have the capacity to undertake these procedures in a quality-assured manner.
- However, experts have held that guidelines are not necessarily binding and it is too early to dismiss convalescent plasma therapy.
- The ICMR is now considering removing the option of CPT from the national guidelines.
Way Forward
- Covid-19 is a new virus and global evidence is still emerging on the best therapeutic options so it is too early to take a firm step.
- For example, remdesivir has been sanctioned as a drug of choice by the USA drug regulator, while the World Health Organization’s Solidarity Trial has found it had little or no effect on 28-day Covid mortality.
- Care for Covid-19 is individualised care and the use of the right drugs in the right patient does work. Some of the therapies can be continued on compassionate grounds and the results of one or two trials should not lead to the elimination of an entire treatment or therapy.