The Food and Drug Administration is asking federal courts on opposite sides of the country to permanently stop two stem cell companies from operating after reports of patients being blinded by their treatments.

In a statement Wednesday announcing the injunction request, the FDA said U.S. Stem Cell Clinic in Florida, the Cell Surgical Network in California and others like them are exploiting patients desperate for cures and causing some of them “serious and permanent harm.” The agency said both companies “have continued to disregard the law” and marketed products without regulatory approval.

Hundreds of such clinics have popped up across the country in recent years, many promoting treatments for conditions including Parkinson’s disease, autism and multiple sclerosis. Federal regulators have not approved any of their procedures, and critics liken the facilities to modern-day snake-oil salesmen.

Many stem cell researchers and former patients have long urged the FDA to take stronger action against the clinics. Current and former agency officials have acknowledged the need for greater regulation of the booming industry, citing limited resources for the lack of aggressive action in the past.

“It’s important that we send a stronger deterrent message. If people are putting patients at risk and creating patient harm, we’re going to take action,” Commissioner Scott Gottlieb said Wednesday. He noted that the injunction request is the latest in a series of moves the FDA has made since he took office a year ago, and he said more is planned in coming months, including warning letters to other stem cell clinics.

“From my standpoint, this is a field where there’s a lot of medical promise, but we also see bad actors putting people at risk, harming patients and peddling false hope,” Gottlieb said.

The co-founder of Cell Surgical Network, the largest group of independent stem cell clinics in the country, called the FDA's court action “ridiculous.” Beverly Hills plastic surgeon Mark Berman said the treatments the network's 100 clinics provide should not count as drugs that require FDA regulation because they consist of stem cells derived from fat suctioned out of patients' own bodies.

“They would have to go out of the way to claim your own personal cells that are taken out of your own body are drugs,” said Berman, who said his company has retained several Washington-area lawyers and would fight the injunction case all the way to the Supreme Court if necessary.

Berman's partner, network co-founder Elliot Lander, said there were “a lot bigger issues at stake than our business. When we do these surgical procedures, we are giving patients access to healing cells in their own body. If it had to be approved as a drug product, it would take hundreds of millions dollars and years to achieve that.”

U.S. Stem Cell Clinic said in a statement that it plans to vigorously fight the injunction in court.

“My entire career has been dedicated to studying and developing treatments utilizing the body’s own natural ability to heal,” said the company’s chief science officer, Kristin Comella. “I remain steadfast that no government agency should deprive individuals of their right to harness the cells that exist in their body.”

If granted, the injunction against the two companies would stop all of their clinics from marketing stem cell treatments without FDA approval. The FDA had issued warnings to both companies last year, and in its complaint to federal courts, the agency said both had ignored those warnings and continued to operate, putting patients at risk.

Each company has been sued by patients who sought treatment for deteriorating vision because of disease but say they went blind after the clinics injected stem cells into their eyes.

One Florida woman suffering from macular degeneration, whose case was documented last month by The Washington Post, described how a Cell Surgical Network clinic in Georgia suctioned fat from her belly and then injected the stem cells from that tissue into both of her eyes. Within months, Doris Tyler said, she was completely blind.

Andrew Yaffa, who is representing Tyler in litigation against Cell Surgical Network as well as another patient who also went blind and is suing U.S. Stem Cell Clinic, called the injunction action long overdue. “Thank goodness the FDA is finally taking appropriate action,” he said. “There are so many patients desperate for help and these clinics are capitalizing and manipulating their hope for help.”

Leigh Turner, a University of Minnesota bioethicist, has compiled a comprehensive database of stem cell clinics. By his count, more than 700 clinics are operating in the United States. He described the two companies named in Wednesday's FDA action as among the most notorious in the industry for marketing unproven treatments for incurable diseases.

“The U.S. direct-to-consumer marketplace for stem cell interventions has been out of control, with hundreds of so-called clinics proliferating across the country,” he said. “Businesses should not be allowed to use predatory marketing practices and misrepresentations to take advantage of vulnerable, desperate, often seriously ill individuals. I’m glad to see the FDA finally do something about these clinics.”

Read more:

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What you should know about stem cells, from promising research to dubious uses

Unproven stem cell treatments touted on federal database Clinicaltrials.gov, study says