A clinical drug trial conducted with the palbociclib manufactured by Pfizer showed the medication was able to delay the progression of breast cancer by almost two years.
The trial was part of a study of Phase 2 on 165 women who had breast cancer. Researchers were able to find that women treated with the drug as well as letrozole a hormone drug lived for 20.2 months prior to the cancer becoming worse. Those results were compared to just over 10 months for those patients who received only letrozole hormone drug.
Pfizer said that palbociclib was one of the pharmaceutical giant’s most important medications. Some industry analysts claim that once this drug has been received regulatory approval, it most likely will have sales in excess of $5 billion annually.
The medication is to be used for women who are post-menopausal with newly diagnosed or locally advance breast cancer, which has spread into other areas of their body.
All the women that participated in the trial had estrogen receptor and HER2-negative cancer.
Recent statistics show 60% of the cases of breast cancer that is advanced are HER2-negative and estrogen receptor positive.
Letrozole is a drug than is an estrogen blocker which Novartis AG sells under the name Femara. Women treated with Femara alone have a 33.3 month overall survival rate.
Scientists found that when Letrozole is given together with palbociclib, the survival rate overall increased by over 37 months.
The U.S. Food and Drug Administration granted palbociclib breakthrough status. It is not certain if manufacturers of the drug will decide to seek an accelerated approval due to the trial results.
However, researchers have said that even though just 30 patients that were in each section of the trial of 165 patients had died, more time was needed to make a definition of the impact on the survival rate the drug has.
Today, the second deadliest cancer amongst women in the United States is breast cancer. The cancer affects more than 200,000 annually, killing nearly 40,000 each year.
Experts estimate that one in every eight females will at some time in their lives develop breast cancer.
While there is no known cause risk factors do include late menopause, early puberty and certain types of genes.