Tykerb, an experimental drug, helps stall advanced breast cancer, said makers GlaxoSmithkline at the American Society of Clinical Oncology, Atlanta, USA. Glaxo said women who had not benefited from Herceptin, another breast cancer drug, benefited when receiving Tykerb.

Tyberb, taken along with Xeloda was shown to be twice as effective in slowing down an aggressive type of breast cancer as Xeloda alone.

Tykerb, a pill, blocks proteins that encourage the development and spread of cancer.

Even though Tykerb is still an experimental drug, it is a potential rival to Herceptin, which belongs to Genentech and its parent company, Roche.

About 400,000 women are diagnosed with breast cancer globally each year. After lung cancer, it is the second leading cause of female cancer-related deaths in most developed countries.

In a study of 321 women, all with advanced breast cancer who tested positive for HER2, 160 who received Tykerb with Xeloda had no cancer growth for 36.9 weeks. The other 161 women who were on Xeloda alone experienced no cancer growth for just 19.7 weeks. The trial was stopped so that the women who were not taking Tykerb could do so if they wished.

HER2 is a protein which makes breast cancer more aggressive.

Glaxo is planning to apply for FDA approval for Tykerb later on this year.

Tykerb and Herceptin work in different ways. Herceptin does not enter the cancer cell to block HER2, it binds to the outside of the cell. Tykerb, on the other hand, enters the cancer cell and blocks the protein. Tykerb was also created to block EGFR.

So far, the heart failure side-effect found among some patients taking Herceptin has not so far been detected with Tykerb.

Tykerb is taken once a day as a pill. Herceptin is taken once a month as an infusion.

Written by: Christian Nordqvist
Editor: Medical News Today