Moderna says new Covid vaccine showed stronger immune response than current shot in study

A nurse fills a syringe with Moderna Covid-19 vaccine.Fred Tanneau | Afp | Getty Images

Moderna on Tuesday said a new version of its Covid vaccine triggered a stronger immune response against the virus than its current shot in a late-stage trial.

The results come as Moderna competes with rival Pfizer for more share of the Covid vaccine market and tries to diversify its revenue streams after the world saw a plunge in demand for Covid products last year. Moderna's current Covid vaccine, known as Spikevax, is its only commercially available product.

The biotech company's new shot could offer a longer shelf life and easier storage than its Covid vaccine.

Moderna's new shot is designed to last longer when refrigerated. That could make the jab easier to distribute around the world, especially in developing countries that may not have freezer capabilities. The company will accomplish that by shortening the length of the mRNA strand in the vaccine, Moderna previously told CNBC.

The new shot is also a “critical component” of Moderna's combination vaccine targeting Covid and the flu, the company said in a release. Both Moderna and Pfizer have said that the convenience of receiving protection against two viruses at once could encourage more people to get vaccinated against Covid.

The phase three trial followed roughly 11,400 people ages 12 and older in the U.S., U.K. and Canada.

Moderna's new shot specifically triggered a higher immune response against omicron subvariants BA.4 and BA.5 and the original strain of the virus than the company's bivalent vaccine targeting those variants. The benefits were “most acutely” seen in patients over the age of 65, who are also at highest risk of severe illness from Covid.

The most common side effects were injection site pain, headache, fatigue, muscle aches and chills, according to the company's release. Overall, Moderna said the safety profile is similar to the approved vaccine Spikevax.

A detailed analysis of the late-stage trial results will be presented at Moderna's vaccines event for investors Wednesday. At the event, the company will highlight other parts of its pipeline.

Moderna is working to develop shots against the flu, cancer and other disease. The company's shot against respiratory syncytial virus is expected to win Food and Drug Administration approval in May.

Moderna has also said it plans to launch up to 15 products in the next five years — a goal it first outlined during its annual research and development day in September.