New breast cancer drug 'slows down progression'

A new breast cancer drug has been shown to slow down the progression of advanced cases of the disease by more than 50%, drug company GlaxoSmithKline said today.

GSK said it had stopped enrolling women on its final phase of clinical trials for oral drug Tykerb after tests revealed it was effective in cases where other drugs, such as Herceptin, had failed.

Tykerb will be submitted to European and US regulators during the second half of this year, more than six months ahead of schedule, a spokesman for the firm said.

Breast cancer is the most common cancer in the UK and accounts for almost one in three of all cancer cases in women.

Around 10-20% of newly diagnosed breast cancer patients have locally advanced or metastatic – cancer which has spread – disease.

The average survival rate for women treated for metastatic breast cancer is two years.

During the trials, Tykerb was shown to be effective against severe breast cancer in cases where breast cancer drug Herceptin has failed.

Women with metastatic cancer who had failed to respond to other cancer drugs were given a combination of Tykerb and Xeloda, an oral chemotherapy treatment, while others were given Xeloda alone.

The trials were to end as soon as the combination drug had been shown to slow down the progression to disease by 50%, expected to be towards the end of this year.

However, this endpoint has been reached more than six months earlier than expected.

“We are extremely encouraged by these data which suggest that Tykerb may offer significant benefits as an oral medication in combination with chemotherapy for patients with advanced or metastatic positive breast cancer, and whose disease has progressed on previous treatment regimens, including Herceptin,” said Paolo Paoletti, senior vice president of the oncology medicine development centre at GSK.

Women currently enrolled in the trial will continue to be followed while those receiving Xeloda alone will be given the option of switching to the combination of Xeloda and Tykerb.

Some 392 patients were included in the study and 321 used in the final analysis.

The most common side-effects experienced with the combined drug were diarrhoea and nausea.

The World Health Organisation reports just over one million cases of breast cancer are diagnosed annually worldwide.