The company also intends to test a new booster injection against the South African variant of the coronavirus
Moderna believes its COVID-19 vaccine protects against new variants of the virus found in the United Kingdom and South Africa, but plans to test a new booster injection against the South African strain, concluding that the immune response may be weakened.
On Monday, the company said in a press release that it found no reduced immune response against the variant found in the U.K., but a reduced response against the strain found in South Africa. That said, the company believes its two-dose regimen will provide robust protection.
Moderna shares rose nearly 10 percent ($12.40) to $143.85 in morning trading.
The emergence of new strains in the U.K., South Africa, and Brazil has raised fears that mutations in the virus could make vaccines less effective.
Jefferies analyst Michael Yee notes that the speed of development of the new booster injection at Moderna proves the flexibility of the new matrix RNA technology on which the vaccine is based.
Moderna said a new booster injection could be developed in the future if needed.
Pfizer and BioNTech also said tests have shown the effectiveness of their vaccine against the variant found in the United Kingdom, but have not yet disclosed the results of tests against the variant from South Africa.
The strain first detected in the U.K. has caused a massive spike in cases in that country and has also been detected in a dozen U.S. states. U.S. health officials expect it to become the dominant strain in the United States within six weeks.
Moderna plans to publish its test data against the new variants on the bioRxiv website.