Massachusetts-based biotech firm Moderna said Thursday that its coronavirus vaccine maintains its effectiveness in preventing symptomatic illness six months after patients receive the shot.
“We are pleased that our COVID-19 vaccine is showing durable efficacy of 93% through six months,” CEO Stéphane Bancel said in a statement.
A clinical study last year found Moderna’s vaccine has 94 percent efficacy, with Thursday’s statement indicating only minimal change after six months. Pfizer and BioNTech, which like Moderna developed their vaccine using mRNA technology, said last month that their vaccine fell from 96% to 84% efficacy after six months.
A recent study in Israel indicated the effectiveness of the Pfizer vaccine may decline by an even larger percent over time.
Israel has predominantly relied on Pfizer’s vaccine to inoculate its population, but has also purchased millions of doses of Moderna’s version.
Bancel warned in the statement that the more transmissible Delta variant “is a significant new threat so we must remain vigilant.”
He added that Moderna is developing COVID booster shots that “demonstrate robust antibody responses” to coronavirus variants during Phase 2 trials.
The company said that it had completed enrollment in an early-stage study of its next-generation COVID-19 vaccine, which could be easier to store and distribute. It also said it will explore a combination vaccine that aims to offer protection against the flu, COVID-19 and other viruses.
Moderna’s COVID-19 vaccine has received emergency authorization for use in more than 50 countries.
The COVID-19 vaccine is Moderna’s only commercially approved product. It is also developing several vaccines that aim to guard against the flu, Zika and HIV among other viruses. Those are all in early stages of clinical testing, according to its website.
The company, which was formed to commercialize mRNA vaccine technology, said it had nearly doubled in size over the past year, from 930 employees to around 1,800. It reported $4.35 billion in total revenue, thanks to the vaccine and some grants.