AstraZeneca Plc's experimental treatment for lupus failed to meet the goal of a late-stage trial, a blow to the drugmaker's efforts to develop a rare new therapy for the potentially life-threatening disease.

Patients with moderate to severe cases of lupus who got the drug, called anifrolumab, didn't see a statistically significant reduction in disease activity compared with those who received a placebo in the yearlong study, Cambridge, England-based AstraZeneca said Friday in a statement.

With anifrolumab, AstraZeneca was working to develop just the second new therapy for lupus in 60 years. About 5 million people worldwide have some form of the hard-to-treat condition in which the immune system can attack the kidneys, skin, brain and other organs, according to the Lupus Foundation of America. Current therapies, such as steroids and immune suppressants, can have harsh side effects when used over the long term.

“The result of this trial is disappointing for patients and the lupus community,” said Sean Bohen, Astra's executive vice president for global medicines development, in the statement.

Astra fell as much as 1.1 percent in early London trading.

Anifrolumab is one of a number of new medications that Chief Executive Officer Pascal Soriot has been working to get to market in his efforts to make AstraZeneca a leader in pharma innovation. Analysts' average estimate for sales of the drug in 2022 was $217 million.

An antibody that blocks a cellular receptor for an immune system messenger, anifrolumab was hoped to reduce harmful inflammation in lupus patients. It had produced positive results in earlier studies, raising hopes of a new option for patients with stubborn cases.

A full evaluation of the data from the trial, called Tulip 1, will be conducted later this year, Astra said.