IRESSA Shows Encouraging Antitumor Activity in Phase I Clinical Trials

Strategic Insights -

Preliminary results from phase I clinical trials suggest that the novel anticancer compound, IRESSA (ZD1839), shows promise in treating non-small cell lung cancer. Researchers from AstraZeneca presented the findings at the American Society of Clinical Oncology (ASCO) annual meeting in New Orleans. The study involved 64 patients who had received and progressed on at least one prior chemotherapy regimen, and the results indicate that IRESSA is well-tolerated and demonstrates predictable pharmacokinetics.

Key Takeaways:

  • IRESSA, developed by AstraZeneca, has shown encouraging antitumor activity, particularly in non-small cell lung cancer (NSCLC), in a small group of patients in phase I clinical trials.
  • The compound was well-tolerated, with the most common adverse events being mild to moderate diarrhea and acne-like skin rash.
  • Serious adverse events were rare and usually related to disease progression.
  • Dose-limiting toxicity was observed at the 700-mg dose level.
  • The study involved 64 patients (25 male, 39 female; median age 54) with solid malignant tumors known to express or over-express epidermal growth factor receptors (EGFR).
  • 15 patients with a range of tumor types had stable disease or response for greater than or equal to 4 months.
  • Antitumor activity was most evident among the 16 non-small cell lung cancer patients.
  • The mechanism of action of IRESSA involves blocking signals within the cancer cells by inhibiting the epidermal growth factor receptor (EGFR) tyrosine kinase enzyme.
  • AstraZeneca is committed to further research and development of IRESSA, with plans to widen the research program and initiate phase III studies in advanced NSCLC.
  • Background on IRESSA was presented, focusing on its mechanism of action, target, and overall potential as a promising new approach to treating cancer.

Statistics:

  • 64 patients were enrolled in the trial.
  • 25 male and 39 female patients participated in the study.
  • Median age of participants was 54 years.
  • 15 patients had stable disease or response for greater than or equal to 4 months.
  • Antitumor activity was most evident among the 16 non-small cell lung cancer patients.
  • Serious adverse events were rare.
  • Dose-limiting toxicity was observed in 1 patient at the 700-mg dose level.

Sources:

  • 1) Ferry D, Hammond L, Ranson M, Kris M, Miller V, Murray P, Tullo A, Feyereislova A, Averbuch S, Rowinsky E. Intermittent oral ZD1839 (Iressa), a novel epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TK), shows evidence of good tolerability and activity: Final results from a Phase I study. Presentation, American Society of Clinical Oncology Annual Meeting, New Orleans, May 23, 2000.
  • 2) American Cancer Society; Cancer Facts & Figures-2000 Special Section: Lung Cancer.
  • 3) American Lung Association; Facts About Lung Cancer: www.lungusa.org (accessed 05.01.00).