Food and Drug Administration Commissioner Scott Gottlieb, who launched a campaign against teen vaping and approved a record number of generic drugs, is resigning next month.

The departure raises questions about whether the agency would continue to vigorously seek to curb the exploding use of e-cigarettes among young people, among other Gottlieb initiatives. But the commissioner, in a resignation letter listing accomplishments on this and other issues, said he was “confident that the FDA will continue to advance all these efforts.”

Gottlieb took pride in the agency’s recent enforcement actions. “We cracked down on bogus stem cell therapies, on sham homeopathy, on unsafe medical device products, on tobacco sales to minors, on unsafe dietary supplements, and on kratom,” he said in his letter.

He tweeted that he was grateful for the support of his colleagues, President Donald Trump and Health and Human Services Secretary Alex Azar in supporting public health goals.

I’m immensely grateful for the opportunity to help lead this wonderful agency, for the support of my colleagues, for the public health goals we advanced together, and the strong support of @SecAzar and @realDonaldTrump – This has been a wonderful journey and parting is very hard. https://t.co/1Zu9y7NTwR

— Scott Gottlieb, M.D. (@SGottliebFDA) March 5, 2019

“Scott has helped us to lower drug prices, get a record number of generic drugs approved and onto the market, and so many other things. He and his talents will be greatly missed!” Trump tweeted.

Gottlieb, who was sworn in as commissioner in May 2017, is the rare Trump administration official who maintained good relationships on both sides of the aisle. Gottlieb was seen as sensitive to public demands on issues like drug prices and opioid abuse.

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After Trump’s election, Gottlieb had widely been viewed as the front-runner to lead the agency. He was a senior official at the FDA and the Centers for Medicare and Medicaid Services during the George W. Bush administration. After leaving government, he was a fellow at the American Enterprise institute and a consultant for a wide range of FDA-regulated products, including drug and medical device companies.

Those ties were his greatest liability as a nominee, but he undertook the required divestitures and avoided the ethical pitfalls that have befallen other Trump administration officials. Fears that he would be an FDA commissioner overly friendly to industry largely didn’t materialize in most cases, especially since Congress has written laws in recent years requiring the FDA to allow smaller or shorter studies for drug and device approvals.

But Michael Carome, director of the health research group at consumer watchdog Public Citizen, pointed to two issues with potentially adverse impacts. One was the November decision to approve Dsuvia, a powerful opioid. Another was a December decision to pull a proposed rule — stalled since the Obama administration — that would have required generic drugmakers to update their labels when new safety information came to light.

“His tenure as commissioner was marked by regulatory decision making regarding medications and medical devices that tilted further in favor of industry’s financial interests rather than the interests of public health,” said Carome in a statement.

Gottlieb, starting with his confirmation hearings, was ready to acknowledge the FDA’s role in helping cheaper drugs come to market. He approved a record number of generic drugs in an effort to clear a backlog and bring down drug prices.

He frequently called out the drug industry for anti-competitive “shenanigans” but also weighed in on the role that insurers and middlemen play in pricing, imploring payers to stop striking deals that dampen the market for generic biologic medicines.

Record

Gottlieb was particularly deft at maintaining relationships on Capitol Hill after a mostly partisan confirmation vote in 2017. His inner office included Republican staff alumni of the Energy and Commerce Committee and the Senate Health, Education, Labor and Pensions committees. He recently hired Doug Andres, who last worked for former Speaker Paul D. Ryan of Wisconsin.

The commissioner made efforts to win over Democrats, often by focusing on granting some of their parochial requests. He appeased members of New England delegations by accommodating exceptions for added sugar labeling in honey and maple syrup, and won over dairy country lawmakers by opening up a process to consider whether plant-based milks can really be called “milk.”

He also addressed longstanding issues with an implantable form of birth control, Essure, by inviting concerned patients and lawmakers such as senior appropriator Rosa DeLauro, D-Conn., to meet with FDA staff. The device was eventually pulled from the market.

Many public health advocates largely praised his plans to limit youth e-cigarette use but urged the FDA to do more.

Early on, Gottlieb had decided to delay regulatory oversight of e-cigarette manufacturers. The Obama administration in 2016 had proposed regulating the industry as well as other products including cigars and hookah tobacco, but the Trump administration pushed that off. E-cigarette manufacturers received a reprieve until 2022.

In more recent months, Gottlieb said he was alarmed at the dramatic rise in vaping by teens who could become addicted to nicotine. He took steps to start the process to ban menthol in traditional cigarettes and limit sales of flavored e-cigarettes to youths.

Some Democrats thought his attempt to preserve access to flavors for adult smokers would leave open many avenues to youth vaping.

On the other hand, his proposed ban on cigarettes flavored with menthol frustrated Sen. Richard M. Burr, R-N.C. Even though Gottlieb’s deputy commissioner for legislative affairs is a former Burr staffer, Anna Abram, Burr has taken to the Senate floor in recent months to rage against Gottlieb.

But Burr still praised Gottlieb upon news of his resignation, calling him “potentially one of the best commissioners we’ve ever had.”

“I had differences between a lot of people in the FDA,” Burr said. “That just happened to be one of them.”

Gottlieb’s departure could put his tobacco policies at risk of being undone or remaining in regulatory limbo.

“We think this major development will be broadly viewed as a positive for the tobacco industry, although this introduces some uncertainty,” Bonnie Herzog, an analyst for Wells Fargo, said in a note to investors shortly after the announcement. “We believe his resignation calls into question whether or not the FDA will in fact enforce harsher regulations around youth e-cig usage/access, cig nicotine limits and a cig menthol ban given he was the champion behind these initiatives.”

On food safety, Gottlieb’s record was mixed. His appointment of former Walmart executive Frank Yiannis to lead the agency’s food efforts was widely seen as good news, given the retail giant’s use of tracking technology to ensure vendor compliance.

But the FDA’s decision to delay produce farm inspections required under a 2011 food safety law was criticized by members like DeLauro, particularly after several high profile outbreaks from contaminated lettuce in 2018.

News of Gottlieb’s departure, first reported by The Washington Post, follows his denial in January to media inquiries about his potential resignation.

“I want to be very clear — I’m not leaving,” he tweeted. “We’ve got a lot important policy we’ll advance this year. I look forward to sharing my 2019 strategic roadmap soon.”

As Gottlieb’s resignation was confirmed Tuesday, Azar called the commissioner “an exemplary public health leader, aggressive advocate for American patients, and passionate promoter of innovation.”

“Scott’s leadership inspired historic results from the FDA team, which delivered record approvals of both innovative treatments and affordable generic drugs, while advancing important policies to confront opioid addiction, tobacco and youth e-cigarette use, chronic disease, and more,” Azar said.

Sandhya Raman contributed to this report.