Trastuzumab (herceptin) for metastasized breast cancer

Findings by SBU Alert  

Version: 1

Method and target group

Trastuzumab (Herceptin) is a new drug for treating patients with metastasized breast cancer. It is prescribed with the aim to inhibit growth of cancer cells that demonstrate a high prevalence (overexpression) of a particular protein on the cell surface, which can be found in cancer cells from approximately 25 percent of all new cases of breast cancer in women. The drug is delivered via infusion once per week. The target group includes patients who have experienced a relapse of breast cancer and where the tumor overexpresses the HER2 protein at a grade of 3+, and for which conventional hormone treatment or chemotherapy has been unsuccessful. The target group is estimated at 200 to 500 patients per year.

Patient benefits, complications, and side effects

The results of one randomized study show that trastuzumab as adjuvant therapy to chemotherapy for metastasized breast cancer extends median survival from 20 to 25 months. However, the addition of trastuzumab somewhat increases the risk for side effects, for example, some studies report severe heart problems in comparison to treatment with chemotherapy alone.

Economic aspects

The cost of trastuzumab is approximately 5600 SEK per treatment week. No scientific studies have investigated the cost effectiveness (cost per life-month gained) of the drug. Since the average length of treatment time has not been established, the expected treatment costs for using trastuzumab cannot be estimated with any degree of precision. The cost per patient is estimated to be high while the total effect on drug costs is expected to be moderate.

Scientific evidence

Alert finds that there is moderate* scientific documentation on the medical effects and risks of using trastuzumab to treat metastasized disease. Currently, no* scientific documentation addresses its cost and cost effectiveness. Although studies have been planned. There is currently no scientific evidence to show that trastuzumab has any positive effects in the primary treatment of breast cancer, although studies have been planned.

Given the limited scientific evidence, systematic followup of survival and side effects should be carried out. Furthermore, there is a need for economic analyses of cost effectiveness based on Swedish conditions.

*This assessment by SBU Alert uses a 4-point scale to grade the quality and evidence of the scientific documentation. The grades indicate: (1) good, (2) moderate, (3) poor, or (4) no scientific evidence on the subject.

This summary is based on a report prepared at SBU in collaboration with Prof. Jonas Bergh, Karolinska Hospital and Karolinska Intitute, Stockholm. It has been reviewed by Bertil Johnsson, MD, Medical Products Agency.

The complete report is available in Swedish only.

Alert is a joint effort by the Swedish Council on Technology Assessment in Health Care (SBU), the Medical Products Agency, the National Board of Health and Welfare, and the Federation of Swedish County Councils.

References

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2. Cobleigh MA, Vogel CL, Tripathy D, Robert NJ, Scholl S, Fehrenbacher L, Wolter JM, Paton V, Shak S, Lieberman G, Slamon DJ. Multinational study of the efficacy and safety of humanized anti-HER2 monoclonal antibody in women who have HER2-overexpressing metastatic breast cancer that has progressed after chemoterapy for metastatic disease. J Clin Oncol 1999;17:2639-48.
3. Early Breast Cancer Trialists´ Collaborative Group. Systemic treatment of early breast cancer by hormonal, cytotoxic, or immune therapy. Lancet 1992;339:1-15,71-85.
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6. Läkemedelsverket, Produktresumé om Herceptin http://www.eudra.org/humandocs/PDFs/EPAR/Herceptin/177400sv4.pdf
7. Norton L, Slamon D, Leyland-Jones B et al. Overall survival (OS) advantage to simultaneous chemotherapy (CRx) plus the humanized anti-Her2 monoclonal antibody Herceptin (H) in Her2-overexpressing (Her2+) metastatic breast cancer (MBC). Proceedings of ASCO, 1999, abstract 483.
8. Roche. Investigator brochure, Genetech Inc/F.Hoffman La Roche Ltd 2000, 18 september.
9. Slamon D, Clark G, Wong S et al. Human breast cancer: correlation of relapse and survival with amplification of the Her2/Neu oncogene. Science 1987;235:177-182.
10. Slamon D, Leyland-Jones B, Shak S et al Addition of Herceptin (humanized anti-Her2 antibody) to first line chemotherapy for Her2 overexpressing metastatic breast cancer (Her2+/MCB) markedly increases anticancer activity: A randomized, multinational controlled phase III trial. Proceedings of ASCO, 1998, abstract 377.
11. Slamon D, Leyland-Jones B, Shak S. Herceptin ® improves time to progression following chemotherapy in women with metastatic breast cancer. ECCO 10. The European Cancer Conference, 12-16 September 1999. In: Eur J Cancer 1999;35,suppl 4 abstract 1261.