In a surprise announcement Tuesday, Scott Gottlieb said he was resigning as FDA commissioner, effective in one month.

His resignation letter included a list of FDA achievements during his nearly two-year tenure as head of the agency, but it gave no reason for his resignation. Just two months ago, Gottlieb responded to speculation that he was leaving the FDA with a tweet saying, "Let me be very clear – I'm not leaving. We got a lot [of] important policy we'll advance this year. I look forward to sharing my 2019 strategic roadmap soon."

When Gottlieb testified last week before a House Appropriations subcommittee about the status of the FDA, there was not a whiff of an impending resignation. His work at the agency was praised by Republicans and Democrats alike. Rep. Mark Pocan (D-Wis.) even invited the commissioner to come for a visit in Wisconsin, but advised him that he might want to wait for warmer weather. (See BioWorld, March 1, 2019.)

Health and Human Services Secretary Alex Azar was the first to comment on Gottlieb's resignation, saying that his leadership has "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. The public health of our country is better off for the work Scott and the entire FDA team have done over the last two years."

Azar called Gottlieb "an exemplary public health leader, aggressive advocate for American patients, and passionate promoter of innovation," adding that he will personally miss working with Gottlieb.

President Donald Trump tweeted that Gottlieb "has done an absolutely terrific job" at the helm of the FDA. "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," the president said.

Wishing Gottlieb well in the future, Scott Whitaker, president and CEO of the Advanced Medical Technology Association, said, "During his tenure as FDA commissioner, Dr. Gottlieb has been a tireless advocate for improved patient care and for promoting innovative solutions to our most pressing health challenges, including greater use of med tech to combat the opioid crises."

Chad Landmon, chair of Axinn's Intellectual Property and FDA practice groups, expressed surprise at the resignation. "Gottlieb was generally regarded as one of the superstars of the Trump administration," Landmon said. "He is obviously very outspoken, including his prolific use of Twitter, and he has been very active in spreading the word on FDA's initiatives across a broad spectrum of areas."

One of the hallmarks of Gottlieb's time at the FDA is a changing view on the agency's part in drug prices. "Focusing on reducing drug costs has been a dramatic shift in the thinking at FDA, which traditionally has said that it plays no role in the overall costs of drugs," Landmon said. "But Commissioner Gottlieb has pushed back on that, asserting that FDA can play a role by using free market principles of increased competition to reduce overall costs."

As the news spread of his resignation, Gottlieb tweeted, "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."