The American company, Moderna, announced in a statement that “the protection provided by its vaccine against Covid-19 has remained strong for at least six months, and that the booster doses of anti-mutants being tested generated a strong response to antibodies to the delta mutant.”

In a final analysis from a phase III and final clinical trial, Moderna’s vaccine showed an efficacy of 93% over six months after the second dose.

The company is also conducting clinical trials of three different anti-Covid-19 enhancers that all produce high levels of antibodies against the original coronavirus strain and mutants of concern, including Delta.

“We are pleased that our COVID-19 vaccine shows a sustained efficacy of 93% over a six-month period, but we recognize that the delta mutant represents a significant new threat, so we must remain vigilant,” CEO Stephane Bancel said in a statement.

The statement added, “Moderna expects to submit its application for full approval of its vaccine from the US Food and Drug Administration this month. The company has also started studies on many other vaccines, including against influenza, Zika, respiratory syncytial virus that specifically affects children, and others, and is working to develop an anti-Covid vaccine that can be stored at normal refrigerator temperature.”