Advertise With UsAdvertise on our extensive network of industry websites and newsletters.
Get the PBR newsletterSign up to our free email to get all the latest PBR
news.GlaxoSmithKline has announced positive new data from a large, pivotal phase III study of its small molecule dual kinase inhibitor, Tykerb, in breast cancer patients.
Subscribe to our email newsletter
In the study, the combination of Tykerb (lapatinib ditosylate) and Roche's Xeloda (capecitabine) versus capecitabine alone nearly doubled time to progression (36.9 weeks in the combination arm versus 19.7 weeks with capecitabine alone) in women with refractory advanced or metastatic ErbB2 positive breast cancer whose disease had progressed following treatment with Genentech's Herceptin (trastuzumab) and other cancer therapies.
In April 2006, GSK stopped enrollment of the study based on the unanimous recommendation of an independent data monitoring committee (IDMC) because it had met its primary endpoint of time to disease progression, and exceeded the predetermined stopping criteria outlined in the committee charter.
“Because ErbB2 positive breast cancer may eventually progress during or following treatment with trastuzumab, there has been a need for an effective alternative treatment that can successfully block the function of ErbB2 in another way,” said Dr Charles Geyer, director of breast medical oncology at Allegheny General Hospital in Pennsylvania and principal investigator for this trial. “These results indicate that lapatinib can provide a needed alternative when trastuzumab no longer appears to be helping to control the disease.”
Another study has also provided preliminary evidence suggesting that Tykerb may be effective in treating brain metastases associated with breast cancer. Treatment for brain metastases is an area of significant unmet medical need as one-third of women with ErbB2 overexpression and metastatic breast cancer develop central nervous system (CNS) or brain metastases.
Data from this phase II trial show that two patients achieved partial response as measured by RECIST, a linear measure of solid tumors. An additional five patients achieved stable disease for greater than or equal to 16 weeks.
Furthermore, eight of the patients (40%) showed volumetric decline in CNS lesions – five patients showed greater than or equal to 30% volumetric decline and an additional three patients showed 15-30% volumetric decline.
Although the trial did not demonstrate the hypothesized level of activity as assessed by RECIST, the study investigators conclude that there is sufficient evidence of preliminary clinical effect to suggest that Tykerb can penetrate the CNS.
GSK plans to file for regulatory approval of Tykerb in the US and Europe in the second half of 2006.