TYKERB® (lapatinib) in Combination With Xeloda® (capecitabine): USFDA-approved for the Treatment of Advanced or Metastatic Breast Cancer
March 16, 2007 by Gloria Gamat
Filed under Diseases & Conditions
A product of GlaxoSmithKile Plc – TYKERB® (lapatinib) – has recently been approved by the USFDA, in combination with Xeloda® (capecitabine), for the treatment of patients with advanced or metastatic breast cancer whose tumors overexpress HER2 and who have received prior therapy including an anthracycline, a taxane, and trastuzumab.
TYKERB® (a pdf file) – a small molecule that inhibits the tyrosine kinase components of the EGFR (ErbB1) and HER2 (ErbB2) receptors – is the first targeted, once-daily oral treatment option for the abovementioned patient population.
This approval reflects more than 16 years of research, including more than 60 clinical trials and investigator-initiated collaborative research studies. TYKERB® is designed to interfere with discrete cellular processes or disease mechanisms prevalent in cancer.
Within two weeks of the approval, TYKERB® will be available in the United States.
Find more details from the full report.
Targeted cancer therapies use drugs that block the growth and spread of cancer by interfering with specific molecules involved in carcinogenesis (the process by which normal cells become cancer cells) and tumor growth. By focusing on molecular and cellular changes that are specific to cancer, targeted cancer therapies may be more effective than current treatments and less harmful to normal cells.
However, the monoclonal antibodies like Herceptin and Erbitux are “large” molecules. These very large molecules don’t have a convenient way of getting access to the large majority of cells. Plus, there is multicellular resistance, the drugs affecting only the cells on the outside may not kill these cells if they are in contact with cells on the inside, which are protected from the drug. The cells may pass small molecules back and forth.
Exciting results have come from studies of multitargeted tyrosine kinase inhibitors, “small” molecules that act on multiple receptors in the cancerous cells, like Tykerb and Sutent. Targeted “small-molecule” therapies ruled at the recent annual ASCO meeting of oncologists. The trend is away from the monoclonals to the small molecules, a trend in which a new predictive test may be able to hasten.
The EGFRx™ assay is able to test molecularly-targeted anti-cancer drug therapies like Iressa, Tarceva, Tykerb, Sutent and possibly Nexavar, because of being small molecules. The EGFRx™ assay relies upon a technique known as Whole Cell Profiling, in which living tumor cells are removed from an individual cancer patient and exposed in the laboratory to the new drugs.
Basically, Whole Cell Profiling measures the response of the tumor cells to drug exposure. Following this exposure, it measures both cell metabolism and cell morphology. The effect of drugs on the whole cell, resulting in a cellular response to the drug, measures the interaction of the entire genome.
A variety of metabolic and apoptotic measurements are then used to determine if a specific drug was successful at killing the patient’s cancer cells. The whole cell profiling method differs from other tests in that it assesses the activity of a drug upon combined effect of all cellular processes, using several metabolic (cell metabolism) and morphologic (structure) endpoints, at the cell “population” level.
Other tests, such as those which identify DNA or RNA sequences or expression of individual proteins often examine only one component of a much larger, interactive process. Whole Cell Profiling measures genes before and after drug exposure. Gene Expression Profiles measures the gene expression only in the “resting” state, prior to drug exposure.
Source: http://weisenthal.org/ex_targeted_egfr_kinase.pdf