U.S. biotech firm Moderna's early findings on a coronavirus vaccine reportedly does not provide critical data needed to evaluate its effectiveness.

According to Reuters on Tuesday, health-focused Stat News quoted experts as saying that data from a small, early-stage safety trial testing Moderna's experimental COVID-19 vaccine lacked critical information needed its assess its effectiveness.

Moderna announced on Monday that the vaccine candidate produced protective antibodies in a small group of healthy volunteers.

However, Stat cited experts who said Moderna's press release did not provide enough information about the responses to the medicine from the participants in the study involving 45 subjects, among other data. 

The experts also noted a lack of information about the ages of the eight subjects whose antibodies were analyzed, which is important given the novel coronavirus is particularly lethal to older people. 

They also pointed out that were was not enough comment on the vaccine from Moderna's U.S. government partner, the National Institute for Allergy and Infectious Diseases.