March 5, 2007—Letter to the FDA Regarding the Pending Approval of Lapatinib (Tykerb)
Dr. Richard Pazdur
Director, Office of Oncology Drug Products
Food and Drug Administration, HFD-150
1451 Rockville Pike
Rockville, MD 20852
RE: FDA approval of lapatinib as treatment for metastatic breast cancer
March 5, 2007
Dear Dr. Pazdur,
Breast Cancer Action (BCA), a national education and advocacy organization with over 17,000 members, believes that finding better treatments for metastatic breast cancer patients is a critically important field for developing new drugs. This is especially true in patients for whom all other treatment options have failed. In the study, Lapatinib plus Capecitabine for HER2-Positive Advanced Breast Cancer,1 it appears that lapatinib may be effective at treating women whose breast cancer has progressed after treatment with trastuzumab and for women with central nervous system metastases. However, the use of time to progression as a surrogate endpoint in this study makes it impossible to tell if women will live longer if they take the drug.
The study was designed to test time to progression of disease as a surrogate marker for overall survival. Although lapatinib significantly increased time to progression in this study, no benefit in overall survival was reported. Both the treatment group and the control group experienced the same percentages of deaths.
BCA looks forward to the day when we can say with confidence that a drug is effective at increasing survival for women with metastatic breast cancer. The FDA should not approve drugs that have not shown either a survival benefit or improved quality of life for breast cancer patients with metastatic disease. The FDA should require applicants for drug approval to look at true markers of efficacy so that women can have more meaningful treatment choices.
Respectfully submitted,
Barbara A. Brenner
Executive Director
Breast Cancer Action
As a matter of policy, in order to avoid the fact or appearance of conflict of interest, Breast Cancer Action does not accept funding from Glaxo Smith Kline or any other pharmaceutical company.
1 Charles E. Geyer, et al., “Lapatinib Plus Capecitabine for HER2-Positive Advanced Breast Cancer,” The New England Journal of Medicine 355(26), December 2006, pp. 2733-2743.