Lab Canada

Gemzar combination showed significant efficacy advantage in breast cancer study

Toronto, ON June 2, 2003 According to an interim analysis of Phase III data unveiled at the 39th annual meeting of the American Society of Clinical Oncology (ASCO), women with metastatic breast cancer experienced a significant delay in the progression of their disease when they received a combination of Gemzar (gemcitabine HC1) and Taxol (paclitaxel), compared to Taxol alone.

“Few combinations have surpassed the single-agent efficacy of Taxol in this disease,” said study investigator Dr Martin Blackstein, associate professor of medicine, University of Toronto. “These results could be important for patients with metastatic breast cancer because the Gemzar and Taxol combination provide a more significant response than Taxol alone.”

The international study, which included two Canadian trial sites, involved 529 women who were previously treated with an anthracycline, but had no prior chemotherapy in the metastatic setting. Taxol is commonly used in treating women with metastatic breast cancer under these circumstances.

One treatment arm, comprising 267 women, received repeated 21-day cycles of Taxol and Gemzar (175 mg/m2 of Taxol for three hours on day one followed by 1250 mg/m2 of Gemzar for 30 minutes on day one and day eight). The remaining 262 women received Taxol only (175 mg/m2 for three hours on day one). Patients were treated until progressive disease was documented or an intolerable toxicity developed.

The global trial yielded the following results:

– Median time to disease progression, the primary interim endpoint of the study, was 5.4 months for the Gemzar/Taxol arm and 3.5 months for the Taxol arm, a finding that was statistically significant (p=0.0013). Time to disease progression is a measure of time after cancer is treated until disease starts to get worse.

– Overall response rate was also statistically significant: 39.3% for Gemzar/Taxol patients vs. 25.6% for Taxol patients (p=0.0007).

– Non-hematologic toxicity was moderate in both arms. Grade IV hematologic toxicity was more pronounced in the combination arm, with the most common side effect being neutropenia, or a decrease in white blood cells – 17.2% vs. 6.6% (p=0.0002).

In sum, the researchers concluded this interim analysis of time to disease progression data demonstrated that the Gemzar/Taxol combination showed significant efficacy advantages over single-agent Taxol with manageable side effects.

Eli Lilly Canada says it has filed a submission with Health Canada seeking an expanded indication for Gemzar in the treatment of metastatic breast cancer in combination with Taxol. Combination therapy is a cornerstone method for cancer treatment, offering patients increased survival and improved response rates without compromising tolerability. Clinical data reinforce that combination regimens are shaping the future of cancer care, and will continue to be the focus of research and development in oncology.

Lilly is conducting additional Phase III trials in the US and outside the US involving the combination of Gemzar and taxane agents in the treatment of metastatic breast cancer.