Moderna Inc said on Friday it had asked the EU drugs regulator for conditional approval of a booster shot of its COVID-19 vaccine at a 50 microgram dose.

       The company also said it had completed data submission for the use of a third booster dose of its two-shot vaccine to the U.S. Food and Drug Administration.

       Moderna said clinical study data and additional analyses showed that a 50-microgram booster dose of its COVID-19 vaccine induces robust antibody responses against the Delta variant. The company's original vaccine contains 100 micrograms of mRNA in each shot.

       The submissions come as several countries, including the United States, are already offering or have plans to give booster doses of COVID-19 vaccines to the vulnerable or those with weak immune systems amid the spread of the highly contagious Delta variant.

       The European Centre for Disease Prevention and Control (ECDC) earlier this week said there was no urgent need for booster doses of COVID-19 vaccines for the fully vaccinated.- Reuters