© Andrew Harnik, Associated Press The Food and Drug Administration campus in Silver Spring, Maryland.

The U.S. Food and Drug Administration issued its most stringent warning Friday for a higher-dose version of the Pfizer drug Xeljanz, five months after a clinical trial showed it was linked to blood clots in the lungs and deaths.

The action comes three weeks after questions were raised in a Journal Sentinel story about the agency’s lack of action on the drug under former Commissioner Scott Gottlieb who later took a job on Pfizer’s board of directors.

The criticism continued Friday.

“This is another example of the FDA moving more slowly and less aggressively to protect public health relative to regulators in other countries,” said Michael Carome, a physician with the watchdog group Public Citizen.

In May, regulators in Europe recommended that doctors not prescribe the higher dose to people at risk for blood clots, which include those with ulcerative colitis.

On Friday, the FDA gave higher-dose Xeljanz, which is approved to treat colitis, its prominent black box warning. It also said its use for colitis will be limited to patients who are not treated effectively or who suffer severe side effects from other drugs.

The FDA also released data from a safety trial of the drug in people with rheumatoid arthritis, showing there were 19 blood clots in the lungs in those who got higher-dose Xeljanz compared with three who got other drugs known as TNF blockers.

There also were 45 deaths in those who got high-dose Xeljanz compared with 25 who got TNF blockers.

A lower-dose version of Xeljanz already is approved to treat rheumatoid arthritis and psoriatic arthritis, a form of arthritis that occurs in people with psoriasis.

Asked about why the FDA took longer to act and why it did not go as far as European regulators, FDA spokeswoman Stephanie Caccomo said that as new safety information becomes available, a team evaluates whether there is a new safety concern.

“Interpreting postmarket safety data is complex,” she said. “The FDA takes the safety of approved drugs very seriously. We will update the public when additional information is available.”

After safety concerns were found in February, Pfizer immediately stopped giving the higher dose to those in the trial.

Gottlieb's last day at the FDA was April 5. According to a Pfizer spokesman, the company approached him about the board position after he resigned. Later, on May 24, Pfizer CEO Albert Bourla had preliminary conversations with Gottlieb.

His election to the board was announced June 27.

In an email to the Journal Sentinel earlier this month, Gottlieb said: "Decisions regarding Xeljanz were made by the agency’s career professional staff without my involvement. I did not participate in any matters involving this drug while I was at FDA."

Gottlieb has been under fire for taking the Pfizer job. Critics say the move is an example of a revolving door between the FDA and the pharmaceutical industry it regulates.

After he took the job, U.S. Sen. Elizabeth Warren, D-Mass., a presidential candidate, said Gottlieb should resign from the Pfizer board because it “smacks of corruption.” She said his board membership was worth more than $300,000 a year in cash and stock.

Earlier this month, she told the Journal Sentinel her concerns were underlined by the FDA's handling of the Xeljanz matter.

“Unfortunately, Scott Gottlieb joining the board of Pfizer will raise these kinds of questions about FDA decisions concerning Pfizer, whether it’s this or others," Warren said in a statement to the Journal Sentinel. "He shouldn’t have joined Pfizer’s board."

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This article originally appeared on Milwaukee Journal Sentinel: FDA warning issued for Pfizer drug Xeljanz over clots, deaths