A picture of a patient’s eye one week after receiving stem cell injections from U.S. Stem Cell in 2015 shows widespread retinal hemorrhages. (Thomas Albini)

In a decision expected to send a chill through the booming stem cell industry, a federal judge ruled in favor of the Food and Drug Administration on Monday in a lawsuit against a Florida-based stem cell company whose treatments have blinded at least four patients.

Judge Ursula Ungaro agreed that the FDA has the authority to regulate a procedure that has become widespread in the burgeoning industry — using patients’ fat to create a stem cell treatment.

The judge ruled that the FDA is entitled to an injunction ordering U.S. Stem Cell to halt the procedure.

The judgment represents a major victory for the government, which has increasingly tried to constrain the industry even as it has rapidly expanded in recent years.

“This case is an important victory in the FDA’s work to protect the public health,” the agency said in a statement. “We’ve been taking action, like this case, against clinics that abuse the trust of patients and endanger their health. We will continue to promote the sound and scientific development of regenerative medicine products, but we will not tolerate those in this field who try to skirt the law and put patients in harm’s way.”

Scientists, medical associations and health officials have criticized stem cell clinics for selling treatments unproven by science and unapproved by the government for a wide spectrum of unrelated ailments, such as Parkinson’s disease, multiple sclerosis, joint pain and erectile dysfunction.

“This decision says the FDA has the authority to define a certain kind of stem cell product as a drug product” that requires FDA approval and compliance with other agency rules, said Paul Knoepfler, a stem cell biologist at the University of California at Davis. “There are potentially hundreds of clinics using the same model, and this ruling basically says the FDA can — assuming this is not overturned on appeal — say you are using an unapproved drug, and that’s a big deal.”

Beginning in 2015, at least four patients were blinded after U.S. Stem Cell and clinics associated with the company injected stem cell treatments into their eyes.

The FDA’s slow initial response to patient injuries permitted U.S. Stem Cell to continue operating four years after those first reports of blindness. Although the company stopped injecting its fat-derived treatments into eyes after the patients sued, it continues to sell the therapy to people with spinal injuries, Parkinson’s disease, multiple sclerosis and other serious chronic conditions.

Last year, just three weeks after the government filed suit, an additional patient had a catastrophic reaction after visiting a clinic in South Miami, Fla., that is affiliated with U.S. Stem Cell. A 59-year-old woman felt faint and started vomiting two hours after receiving injections for arthritis pain.

Her case was described in an “adverse event” report filed with the FDA and obtained by The Washington Post through the Freedom of Information Act.