New York, Jan 25 (EFE).- American pharmaceutical company Moderna said Monday that its Covid-19 vaccine neutralizes the British and South African variants of the virus that causes that potentially fatal respiratory illness.

Results from in vitro neutralization studies showed broad effectiveness of the two-dose Moderna vaccine, which has been approved for emergency use in the United States, the European Union, the United Kingdom and elsewhere.

"Vaccination with the Moderna COVID-19 Vaccine produced neutralizing titers (antibody concentration in the blood) against all key emerging variants tested, including B.1.1.7 and B.1.351, first identified in the UK and Republic of South Africa, respectively," the company said in a press release.

There was no reduction in antibody concentration in the case of the British strain relative to earlier variants. A six-fold reduction in neutralizing antibody titers was observed with the South African variant, although the levels were still above what is expected to provide protection.

Even so, the Cambridge, Massachusetts-based company said it will test an additional booster dose - a third dose - of its Covid-19 vaccine to assess "the ability to further increase neutralizing titers against emerging strains beyond the existing primary vaccination series."

Moderna also said it is advancing a variant booster candidate (mRNA-1273.351) for the strain first detected in South Africa, adding that pre-clinical studies and a Phase 1 study will be conducted in the US "to evaluate the immunological benefit of boosting with strain-specific spike proteins."

"We believe it is imperative to be proactive as the virus evolves. We are encouraged by these new data, which reinforce our confidence that the Moderna COVID-19 Vaccine should be protective against these newly detected variants," the company's chief executive officer, Stephane Bancel, was quoted as saying.

Both the British and South African strains are associated with more rapid transmission and a higher viral load (the quantity of virus in a volume of bodily fluid) with respect to prior variants.

Moderna said the clinical results announced Monday are based on in vitro neutralization studies of blood samples obtained from eight people and two non-human primates that received both doses of its vaccine.

The study was conducted in collaboration with the Maryland-based National Institute of Allergy and Infectious Diseases' Vaccine Research Center.

The rate of infection of the British variant of the coronavirus - first detected last September - is "forbiddingly high," British Prime Minister Boris Johnson said last Friday, adding that government researchers have found that it also could be between 30 percent and 40 percent more deadly.

The strain detected in South Africa also is associated with greater transmissibility and a greater viral load relative to earlier variants. EFE

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