LOTRONEX: Officer Foresaw Deadly Effects
"Irritable bowel" remedy pulled after reports of serious injuries.
Wednesday, December 20, 2000 | Print this story
By DAVID WILLMAN, Times Staff Writer
Agency officials agreed in July 1999 to conduct a fast-track medical
review of Lotronex, a pill from Glaxo Wellcome Inc. intended to treat
irritable bowel syndrome in women. To justify such accelerated review, the
FDA must find that the targeted disease is "serious."
Irritable bowel syndrome can result in abdominal pain and frequent
trips to the bathroom. But it neither maims nor kills people.
An FDA medical officer, Dr. John R. Senior, discovered during the
review that four Lotronex patients in clinical studies suffered a
potentially life-threatening complication called ischemic colitis, which
results from inadequate blood flow to the colon.
Senior, a former pharmaceutical industry executive and a
gastrointestinal specialist, knew the rarity of ischemic colitis: Some
physicians can practice for decades without treating a single case.
While some cases would be mild and reversible, Senior wrote, ischemic
colitis "can be catastrophic."
Senior found other troubling results. He warned that 27% of the
patients who took Lotronex in Glaxo's studies experienced constipation. He
noted that not a single patient who took a placebo pill developed ischemic
colitis and that only 5% of the placebo patients got constipated.
Glaxo representatives denied that Lotronex had caused the cases of
ischemic colitis and said any risks could be adequately managed. But Senior
warned of the potential for Lotronex patients to suffer debilitating bowel
injuries or death.
If these were the risks, what were the potential benefits?
FDA reviewers found that Lotronex improved symptoms in only 10% to 20%
of the patients. Still, an FDA advisory committee, whose participants
included a paid consultant to Glaxo, unanimously recommended approval. (The
yes vote voiced by the Glaxo consultant, Dr. Arnold Wald of Pittsburgh, was
invalid, agency officials say, because of his status as a temporary
The FDA had a choice: Withhold approval of Lotronex until Glaxo
undertook a major safety study to assess the drug's link to ischemic colitis
or approve the drug conditioned on a pledge by Glaxo to perform the study in
the following year.
Top FDA officials chose not wait. They approved Lotronex on Feb. 9,
2000. The original labeling said that ischemic colitis had occurred
"infrequently" in the clinical studies and that there was no way to predict
which patient was at highest risk.
It was Lotronex's first approval worldwide. Securities analysts
estimated it would generate sales of up to $2 billion within five years.
A spate of bowel injuries emerged quickly--consistent with Senior's
In June, the FDA's Woodcock embraced the crafting of a "medication
guide" aimed at advising patients of Lotronex's risks. But the leaflets were
not delivered to pharmacies until late September. Meanwhile, Woodcock's
staff proposed a black box warning for Lotronex's label but retreated when
Glaxo publicly opposed the idea.
By October, 49 cases of ischemic colitis in Lotronex
patients--including five deaths--had been reported to the FDA. Records show
that no fewer than 91 patients were hospitalized, many with severe
constipation. Several bowel surgeries, including the removal of a patient's
colon, were performed.
FDA officials who had backed the approval of Lotronex maintained their
support for the drug into November, but staff epidemiologists pointed to the
surgeries and deaths and the likelihood that those voluntarily reported
events were a small fraction of the true scope of harm.
They urged withdrawal.
Glaxo and the FDA announced on Nov. 28 that Lotronex would be pulled
from the U.S. market. At that point, Glaxo's promised study of the drug's
link to ischemic colitis still had not enrolled a single patient.
Asked why the FDA approved Lotronex, given the ischemic colitis risk,
Woodcock indicated that her aides had believed Glaxo's view of the risk more
"At the [November 1999] advisory committee, the company proposed that
these were [unsurprising] incidences of ischemic colitis, not causally
related to drug," Woodcock said, adding: "We can't not approve drugs because
they have certain side effects; they're all going to have side effects. We
have to determine, are they going to be adequately managed?"
In subsequent written comments, Woodcock noted that some patients
complain when a drug they believe helps them is withdrawn.
"People who suffer from serious, life-limiting, or life-threatening
illnesses have repeatedly and forcefully told the FDA that they are willing
to take greater risks because of the nature of their illnesses," Woodcock
told The Times.
A Glaxo executive, Dr. Richard S. Kent, said the company continued to
believe that the risks could be satisfactorily managed through labeling and
During the nine months that Lotronex was on the U.S. market, sales
exceeded $56 million through October, according to the research firm IMS
Health. The drug was never sold in any other nation.