Can Boston startup Whoop win its face-off with the FDA?

Ordinarily, it’s pretty tough to win a dispute with the Food and Drug Administration, the federal agency created in 1906 to regulate the safety of everything from carrots to cardiac stents.

But Whoop, the Boston startup that makes a wearable wristband to monitor all sorts of health indicators, seems to be betting that it has an ally in President Trump’s cabinet: Robert F. Kennedy Jr., whose Department of Health and Human Services oversees the FDA.

Whoop is one of Boston’s most promising tech startups. Founded in 2012 by a trio of Harvard students, the company designed a product for more serious athletes, who wanted more detailed data about their workouts and recovery periods than they could get from a Fitbit or Nike FuelBand, two popular wearables of that era.

Since 2012, the company has attracted users such as Olympic swimmer Katy Ledecky, Los Angeles Lakers star LeBron James and footballer Cristiano Ronaldo.

The illuminated logo atop its Kenmore Square headquarters can be seen from much of Fenway Park. And Whoop has raised more than $400 million in funding, with CEO Will Ahmed saying a public stock offering is “something that we’re looking at over the next two years.”

As the company developed the up-to-date version of its wristband, the Whoop MG, released in May, Ahmed said, it wanted to add an array of new features. One feature was more sophisticated heart monitoring, or electrocardiogram data. Another was data about the wearer’s blood pressure. (The MG stands for “medical-grade.” Users don’t grab the wristband outright, but instead pay $359 per year to get a wristband and access to the Whoop app.)

“We studied blood pressure for years,” he said, “and that includes both the technology innovation required to do it, and the legal framework for introducing it to the world.”

So for the new Whoop MG wristband, the company sought and obtained the FDA’s approval of its heart monitoring technology, which can sound the alarm on problems like atrial fibrillation, a kind of abnormal heart rhythm. But Whoop didn’t get the agency’s OK for its blood pressure data, which Whoop calls an “estimate.” (Whoop delivers this daily estimate after you set it up first with three readings from a traditional blood pressure cuff.)

Why skip the FDA analysis of that particular feature? Ahmed said the blood pressure information is geared to wellness, rather than any kind of diagnosis of a medical condition.

“The FDA has a clear mandate to regulate medical devices that are providing some kind of a diagnosis, and the 21st Century Cures Act” — a 2016 law intended, in part, to speed up the development of new drugs and medical devices, and give patients better access to health data — “makes it very clear that the FDA is not intended to regulate features or capabilities that are intended for wellness,” Ahmed said.

He believes Whoop put the proper disclaimers around the wristband’s blood pressure information, being an estimate. (The company hasn’t released any data showing how these estimates of blood pressure compare to a reading taken using a traditional cuff.)

“There’s an avalanche of peer-reviewed research that, not surprisingly, demonstrates how blood pressure impacts your wellness,” he said. “Blood pressure affects stress. Blood pressure is impacted by exercise and nutrition. It affects sleep. And so we designed a feature to look at blood pressure insights and explain its impact on wellness, and it’s very clear in the Whoop app that it’s intended for wellness …”

Unfortunately, the FDA didn’t agree, and last month a deputy director at the agency sent Whoop a warning letter, demanding that the company stop marketing the “blood pressure insights” feature of its new wristband, or face seizure of its products, an injunction that would force it to stop selling the Whoop MG and possible fines.

The following day, Whoop posted a statement that it didn’t plan to comply.

Ordinarily, when companies push back on this kind of warning letter from the FDA, sometimes they are successful, but “most of the time they are not,” said Bryant Godfrey, chair of the FDA practice at the law firm Foley Hoag LLP, and a former attorney at the agency.

If the FDA decides to go ahead with some kind of fine or injunction, Godfrey said Whoop could sue over the question of whether its blood pressure data makes the new wristband a medical device, as the FDA contends.

And with new leadership in charge at Health and Human Services and the FDA, Godfrey said, “those who are higher up are getting involved with product decisions.” This could be “a situation where Whoop … might be seeing if the FDA would back off the letter.”

One possible wrinkle in the Whoop vs. FDA bout is the potential for a higher up — potentially Secretary Kennedy — to get involved, as Godfrey suggests.

Ahmed is one of the few Boston CEOs who has been spotted in Washington, D.C., with Trump administration officials in recent months, attending a meeting with Kennedy in May, along with a group of other entrepreneurs developing health care technology. After that meeting, Kennedy posted a video that mentioned learning about wearable devices “that can tell you your blood pressure.”

In the video, Kennedy said of the technologies he’d been briefed on, including Whoop’s: “All of these things provide the kind of transparency and the capacity for Americans to take control of their own health care. We’re determined at HHS to sweep away the regulatory barriers and allow these companies to function and flourish in the marketplace …”

But that White House meeting was in May, and Whoop received the warning letter from the FDA in mid-July. Does his comment about sweeping away regulatory barriers not apply to the Whoop wristband’s information about blood pressure? Or is this a case where having a powerful friend will allow Whoop to keep marketing and selling this particular feature of the Whoop MG?

“In today’s political and regulatory climate, anything is possible,” said Shahid Azim, a Boston entrepreneur who has worked on wearable devices. “However, allowing blood pressure metrics [to be] shown in an unvalidated device is contrary to how FDA clearance essentially works. Even with political pressure to relax regulations, its hard to see that the agency compromises on something where false readings could literally be life-threatening.” Azim sees “too much liability, and too many established precedents” for the FDA to give in to Whoop.

We’ll have to see what the FDA does next. A press secretary at the Department of Health and Human Services, Emily Hilliard, wrote to MassLive via email that “the FDA does not discuss possible or ongoing investigations or compliance matters, except with the company involved.”