Tykerb® (lapatinib) plus Taxol® (paclitaxel) appears to provide benefit in the initial treatment of inflammatory breast cancer, according to results published in the Journal of Clinical Oncology.
Inflammatory breast cancer (IBC) is the most aggressive and lethal form of breast cancer. Many of these cancers express the tyrosine kinase receptors HER2 and/or EGFR. Tyrosine kinases are proteins involved in the proliferation and survival of cells. Because tyrosine kinases often function abnormally in cancer cells, drugs that interfere with these proteins play an important role in the treatment of several types of cancer. Tykerb is one such drug. It is an oral medication that targets both HER2 and EGFR.
To evaluate the efficacy, safety, and tolerability of first-line treatment of IBC with daily Tykerb followed by daily Tykerb plus weekly Taxol, researchers studied 49 women. Participants were divided into two groups: those with HER2-positive disease and those with HER2-negative, EGFR-positive disease. (However, due to low patient numbers and results from a parallel study indicating a lack of benefit of Tykerb in HER2-negative, EGFR-positive IBC, this group did not continue on the study.) Patients received 14 days of Tykerb followed by 12 weeks of daily Tykerb and weekly Taxol; they then underwent surgery or additional chemotherapy.
The overall response rate for the HER2-positive group was 78%. Common side effects, including diarrhea, rash, nausea, and alopecia, were consistent with expectations and observed in less than half of these patients.
The researchers concluded that daily Tykerb followed by daily Tykerb plus weekly Taxol is active in the treatment of patients with HER2-positive IBC. The combination was generally well tolerated and without unexpected side effects. There are ongoing randomized trials comparing this new approach versus Taxol and Herceptin in women with locally advanced HER2+ breast cancer.
Reference: Boussen H, Cristofanilli M, Zaks T, et al. Phase II study to evaluate the efficacy and safety of neoadjuvant lapatinib plus paclitaxel in patients with inflammatory breast cancer. Journal of Clinical Oncology [early online publication]. June 7, 2010.