Blanca Morales began inquiring about a transplant after her son Mundo had been ill for four months. His condition initially began with a case of strep throat from his first-grade class, which was typically manageable with antibiotics. However, it soon led to stomach issues. As the youngest of five, Mundo had a mother experienced in handling minor illnesses, and she wasn’t alarmed by a bit of vomiting. She kept pails by her children’s beds, a precaution for such occasions. Yet, this routine situation escalated, and Morales found herself comforting Mundo by the toilet, holding his hair back and catching his vomit in a bucket before ending up in the ER.
The diagnosis of Clostridioides difficile was unfamiliar to Morales. By the third relapse, she could recognize the infection by its distinct smell, a mix of acrid and sweet, reminiscent of burnt plastic and decaying flowers—a scent synonymous with hospitals. The illness was likely triggered by antibiotics used to combat strep in March 2025, which disrupted the bacterial balance in Mundo’s colon, allowing C. diff to thrive.
By April, Mundo had learned to swallow pills to avoid C.-diff-targeting antibiotics via IV, which he called “pokey.” By July, after three rounds of medication, his symptoms of bloody diarrhea temporarily subsided each time but returned after stopping the drugs. Morales sought an alternative solution.
The transplant she was considering was not an organ or tissue transplant but a transfer of gut microbiota from one person to another, known as a fecal microbiota transplant (FMT). This procedure aimed to restore bacterial diversity and suppress C. diff overgrowth. Despite the abundance of the basic material, the treatment itself had become scarce.
By the end of 2024, the Food and Drug Administration (FDA) halted the distribution of fecal transplant material from OpenBiome, a major national stool bank. This left children like Mundo with limited options. “It shouldn’t be this hard to cure a child,” Morales stated.
The issue was partly geographical. Morales and Mundo resided in Las Vegas. Had his illness occurred a year earlier, treatment could have been available nearby through OpenBiome, which had been supplying screened stool to hospitals nationwide, including 17 in Nevada. However, in 2022 and 2023, two companies received FDA approval for drugs derived from human excrement to prevent C. diff recurrence. “The FDA said to us, ‘time to wrap up,'” explained Julie O’Brien, CEO of the OpenBiome Foundation.
According to federal officials, this change closed a risky loophole by preventing nonprofits from sending unregulated microorganisms for treatment now that regulated alternatives existed. However, the new drugs were not approved for children, immunocompromised individuals, or severe C. diff cases.
The drugs also came with high costs, exceeding those of a transplant. Vowst’s list price is $19,680 for 12 pills, while Rebyota’s is $9,411 for one enema bag, as stated by First Databank. Insurers often resisted covering these treatments, particularly for off-label use in cases like Mundo’s. Although FDA approval was intended to safeguard patients and improve access to effective treatments, this wasn’t always the case in the complex realm of American healthcare.
A whiff of the DIY
In 2004, Neil Stollman received an unusual request from a colleague to perform a fecal microbiota transplant on a C. diff patient named Rose. As a gastroenterologist in private practice in Oakland, California, Stollman was accustomed to dealing with gastrointestinal issues, but this request was unusual. Nonetheless, the biological reasoning was sound, and he decided to proceed.
“I allowed that plausible biology to supersede my own ick,” Stollman recalled. “We figured out how to make sort of a milkshake out of it and put it inside Rose. I don’t want to sound hyperbolic, but it was pretty impressive. Rose was sick, Rose got better, and all I did was, you know, put some poop up her tush.”
The concept of FMT is ancient. A 4th-century Chinese medical text described using fecal suspensions to treat gastrointestinal diseases. Reports from the mid-20th century also credited it with saving lives. Stollman was not alone in this revival. In 2008, Alexander Khoruts at the University of Minnesota successfully treated a patient with severe C. diff and demonstrated restoration of her microbial ecosystem through DNA sequencing.
While FMT began to gain acceptance in modern medicine, it retained a DIY aspect, with doctors creating custom mixtures for each patient.
Then, OpenBiome emerged. Inspired by Khoruts’ protocols, the nonprofit aimed to standardize and streamline the process. A microbiology grad student from MIT, after witnessing a friend’s struggle with C. diff, conceived the idea, likening it to a stool bank akin to a blood bank.
OpenBiome’s aim was to make FMT more accessible by ensuring transplants were screened for pathogens beyond HIV and hepatitis C. This initiative reduced barriers for doctors, who could now order FMTs without preparing them themselves. In 2013, Stollman was the first to use an OpenBiome shipment, and over a decade, the organization distributed about 72,000 treatments to over 1,300 hospitals and clinics.
Initially, the FDA was hesitant about these unapproved materials. However, with antibiotics failing many patients, there was little alternative. Annually, about 15,000 Americans were dying from C. diff, and FMT data appeared promising. A trial comparing FMT with vancomycin was halted early due to its effectiveness: 81% of FMT recipients recovered after one dose, rising to 94% after a second dose.
Despite insufficient data for FDA approval, the agency decided to “practice enforcement discretion,” allowing OpenBiome and hospitals to continue FMTs. This decision, however, left some within the agency uneasy about potential precedents. “It’s hard to put the genie back in the bottle,” commented one former FDA employee.
The situation became more complex when OpenBiome’s founders launched Finch Therapeutics, a commercial entity. Competitors raised concerns that OpenBiome’s cost-recovery model might be a prelude to business development. “It was almost like business development,” remarked another former FDA official.
In 2019, a patient died from an FMT involving E. coli, not from OpenBiome, but as part of a clinical trial at a hospital. In early 2020, another patient died from an OpenBiome-sourced FMT containing E. coli, marking the first known transmission in over 55,000 shipments. This heightened regulatory concerns. The arrival of COVID-19 further slowed FMT operations as providers ensured no transmission of the virus.
The subsequent FDA approval of two new drugs provided an opportunity to end enforcement discretion. “Once you had an approved product — a safe, effective alternative — that made it easy to essentially bring the hammer down,” said the second former FDA official.
Rebyota was approved in 2022, followed by Vowst in 2023. Enforcement discretion ended, but hospitals could still conduct in-house FMTs. In October 2024, physicians and patient advocates requested the FDA to extend discretion for OpenBiome for patients not covered by the new drugs. The request was denied.
“I was in shock. I was nearly in tears,” said Stacy Kahn, a gastroenterologist at Boston Children’s Hospital. She was treating a child with C. diff who hadn’t responded to antibiotics and was in the ICU. “I was calling OpenBiome, and I was like, ‘We have a child who is not going to make it if we don’t get these.’” Her team managed to secure the necessary materials, saving the child’s life. But that was her last FMT before OpenBiome ceased shipments. Some doctors disposed of their remaining supplies.
‘We all feared that Mundo was going to die’
Initially, Mundo’s gastroenterologist was hesitant about FMT, wanting to try more antibiotics first. Morales, not wanting to upset the doctor or make Mundo appear as a difficult patient, agreed. However, by September, after another relapse and another hospital stay, Morales had reached her limit. Mundo had missed out on birthdays, swimming, and the start of third grade. His cherished long hair, which he believed was the source of his strength, began to fall out.
“We didn’t sleep during that stay,” Morales said, tearfully. “None of us said it, but we all feared that Mundo was going to die.”
Determined, Morales sought FMT. A gastroenterologist recommended it, though it required leaving the state. They considered Los Angeles, a four-hour drive away.
Even in earlier times, FMT economics were complicated. Testing a stool donor for all possible pathogens was costly, and the recipient’s insurance wouldn’t cover screenings performed on someone else. Sometimes, doctors resorted to fabricating illnesses to have the tests covered. “They’d say they have diarrhea and do a bunch of stool tests on the person,” said Libby Hohmann, who manages Massachusetts General Hospital’s stool bank. “That’s insurance fraud. I can’t do that.”
During OpenBiome’s prime, some insurers covered FMT, while others did not, leading to out-of-pocket costs of $2,000 for some patients, according to doctors. Those with C. diff who made it to the University of Minnesota could still receive FMTs at no charge, thanks to a nonprofit established by Peter Westerhaus, whose football career ended due to ulcerative colitis.
Morales started making calls. A number given to her by Mundo’s gastroenterologist’s office led to a hospital front desk in Los Angeles that had no knowledge of FMT, redirecting her to an organ transplant center. After finding the correct contact at Children’s Hospital of Los Angeles, they scheduled an appointment for November. Morales’ husband, who worked in a restaurant, took more time off.
The day of their drive was marked by torrential rain, unusual for the Las Vegas desert, turning dry lake beds into actual lakes. Mundo, from the backseat, wondered if they had reached California, mistaking the flooded terrain for the ocean. A journey that should have taken four hours stretched to nearly eight. Despite the weather, Morales pushed on, fearing missing the appointment could be detrimental. Upon reaching their Airbnb, they rehearsed the next day’s hospital route.
Arriving two hours early for the appointment, Morales was impressed by the doctors’ familiarity with Mundo’s medical history, including his six hospitalizations and six rounds of antibiotics, as well as allergic reactions to one medication. The doctors were attentive and thorough. However, Mundo couldn’t have the procedure. According to the gastroenterologist’s note: “CHLA is not able to offer FMT given Mundo’s age (must be > 12 to enroll in study).”
In an email, a CHLA representative stated that the hospital does provide FMT to children under 12 on a case-by-case basis and declined to comment on the discrepancy between this policy and Mundo’s medical note.
The doctor presented two options to Morales. The first was for Mundo to remain on antibiotics until age 12, at which point he might qualify for a clinical trial if it were still available. The other was Vowst, a medication derived from FMT bacterial spores.
Morales was concerned about long-term antibiotic use but also wary of administering Vowst, as it was only FDA-approved for adults. The gastroenterologist reassured her, having prescribed it to other children. The challenge lay in the cost. “She mentioned the fact that it’s off-label use for children, and the chances of my insurance approving it were really, really low,” Morales said. If denied, the doctor suggested appealing the decision.
Insurance denials, and then a reversal
The end of “enforcement discretion” drastically impacted OpenBiome. “I had to lay off 95% of my staff,” said O’Brien, the CEO. “We are down to two and a half people. We closed our lab, we closed all of our operations.” OpenBiome transitioned into a foundation, focusing on research and sharing FMT expertise. It began preparing to submit documentation to the FDA to resume distribution. This process was complicated by a legal dispute between Finch Therapeutics and Ferring Pharmaceuticals, the latter selling Rebyota. By the time Mundo was in Los Angeles, OpenBiome was readying its research protocol for submission.
The Los Angeles doctors sent a prescription for Vowst to Mundo’s pharmacy in Las Vegas. Morales then tackled the insurance process. She received the first denial on December 9. By the time she contacted the CHLA team, the doctor had already filed an appeal. Two days later, another denial arrived. Morales faxed another appeal on December 30. When she followed up in early January, the company claimed not to have received it. She hand-delivered a paper copy to their offices.
While driving to a mechanic, Morales received a call from the insurer. “They said, ‘We would like to let you know that we received your appeal, but the trustees have told us that you’ve already appealed this, and they denied you a couple of times. They had an outside gastroenterologist look at this, and they decided that your medication is not medically necessary,’” Morales recalled.
It was January 9, and Mundo had been unwell since April. “I was defeated. I had nothing in me left. I just broke down,” she said. “I wanted to throw up.” She had to concentrate on driving.
Morales and her husband discussed alternatives. They considered a DIY FMT but feared the risks. They contemplated selling or refinancing their home to pay the $19,000 for Vowst. Traveling to Minneapolis was another option, but with Immigration and Customs Enforcement active in the city, Morales feared for her family. “We are Hispanic, and our names are very Hispanic,” she said.
Unexpectedly, days later, the same insurance representative called back. “I want to let you know I went into my system, and I was going to send your denial letter for medication, and I noticed that it said ‘pending,’” Morales remembered her saying. “I don’t know if this is good or bad, but I’m letting you know.” On January 15, Mundo’s Vowst prescription was approved.
The 12 pills arrived in early February. Mundo was to take four per day for three days. These pills were larger than those he had previously swallowed to avoid IV antibiotics. It was challenging. In a video Morales recorded, her excitement is audible as Mundo successfully takes the first pill—a step closer to ending this ordeal.
“See, you can do it!”
“That didn’t even feel like nothing,” Mundo says. He holds up the second pill. “I can do this one, second try. Maybe first.”
But then he gags. He tries again, this time getting so far as taking a sip of water—then freezes up and spits it out.
“Put it on the napkin,” Morales instructs. “Dry it, dry it, dry it.” She didn’t want any of these hard-won pills to dissolve before Mundo could reap any benefit. Individually, each one cost $1,640, but to her, they were much more precious than that.
It took Mundo 25 minutes to take his first four capsules. He only had two more days of this to go. When he finished the course, he stayed better. Morales continued looking in the toilet before he flushed, to make sure there wasn’t trouble brewing. “I’m so happy to report they’re the most perfect and beautiful poops I have ever laid eyes on,” she said. “They’re just textbook poop, like the emoji.”
In some ways, this was a success. Mundo’s illness had dissipated after he had received an FDA-approved drug, which was covered by insurance. But the time and effort involved is more than some patients have. Morales is a full-time mom, and it was nearly too much for her. In the case of a patient with severe C. diff who is in the ICU, taking pills may not be an option, and waiting weeks or months for treatment may be too long.
The old version of enforcement discretion is unlikely to return for FMT, though there’s been an administration change and many of the officials involved in closing that loophole in 2024 are no longer at the agency. “FDA recognizes that microbiome-based products are being studied for a variety of diseases, conditions and populations. We continue to work with companies to advance the development of their products. Existing regulatory pathways are applicable,” a spokesperson wrote in an email to STAT.
The agency responded to the OpenBiome Foundation’s protocol by the deadline of March 13 — but only to say that it needed more time to evaluate, and it didn’t indicate when a decision would arrive. Morales hopes it isn’t necessary — but if Mundo’s C. diff does come back, she’ll take him to the University of Minnesota.
