"It will be a significant progress for lung cancer, " says Herbst, also an Iressa trial investigator.
Iressa is only one in a slew of drugs in AstraZeneca's brimming pipeline (see time line).
He was right--Iressa failed in a big clinical trial, and its use was severely restricted.
Now, with the puzzling results from Iressa, it's becoming clear that these are not miracle drugs.
Worse, if Iressa does not complement existing chemotherapies, it will serve a much smaller market.
Natale says he and his colleagues looked at 50 patients who were given Iressa.
Two months later, a paper in Science described why mutations in the gene would make Iressa work.
The results were unambiguous, the statistician intoned without emotion: Iressa didn't boost survival in either big trial.
That's very good news, because in patients who respond, doctors say Iressa is an incredibly powerful drug.
Bernstein, issued a note to investors saying she expected Iressa wouldn't be approved by the FDA panel.
The new data could slow Iressa's path to market, says Catherine Arnold, an analyst at Sanford C.
Iressa's bad clinical results hit not only its maker, but also other firms developing targeted cancer drugs.
By 1999 Zeneca had devised a drug, Iressa, that interrupted the pathways between EGF and tyrosine kinase.
That meant patients lived without their cancer spreading for 9.5 months on Iressa vs. 6.3 months on chemo.
Based on these studies alone, AstraZeneca asked the FDA for accelerated approval of Iressa on Dec. 28, 2001.
But Iressa failed to prove its effectiveness in a large clinical trial, and its use was severely curtailed.
FORBES: AstraZeneca's Victory Highlights Difficulty Of Cancer Drug Development
Investors seem to have given up not only on Iressa, but also on the science behind the drug.
Ultimately, the 14-member advisory panel of oncologists agreed with the FDA that AstraZeneca hadn't proved that Iressa reduces symptoms.
But Iressa patients without the mutations had twice the risk of cancer progression.
Thanks to Iressa, the mother wrote, she made the wedding and felt well enough to dance at the reception.
AstraZeneca has argued that the chemotherapy might somehow have cancelled out the benefits or Iressa, but Warrell is uncertain.
Five years ago, he warned against approving AstraZeneca 's lung cancer pill Iressa because clinical data were not convincing.
Drugs like Iressa target a protein called the epidermal growth factor receptor (EGFR), which tells cells when to divide.
Then, on Aug. 19, AstraZeneca dropped a bombshell: Iressa and chemotherapy didn't work significantly better together than chemotherapy alone.
Bad data on AstraZeneca's Iressa casts a pall over OSI's own development effort.
Standard chemotherapy and Iressa, given together, do not work better than chemo alone.
It could be that Iressa simply did not knock EGF out well enough.
One reason could be that epidermal growth factor, the protein Iressa blocks, wasn't the right one to begin with.
AstraZeneca's Iressa--which is approved for lung cancer and being tested in colon tumors--is a pill, while Erbitux must be injected.
UCLA's Jonsson Cancer Center oncologist Dennis Slamon thinks he knows why Iressa flopped in two large trials: lack of targeting.
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