Biomarkers boost success, cut costs in breast cancer clinical trials

Biomarkers do work. According to an analysis of U.S. new drug approvals in breast cancer, using a validated biomarker can cut the cost of clinical trials and reduce the risk of drug development, the goal of drug R&D everywhere. Even though investment in drug discovery and development is climbing, the number of drugs reaching the market is still stable or falling.

"It's been increasingly difficult for pharmaceutical companies to bring new drugs to market," says Jayson Parker of the University of Toronto. "On average, about 80% of drugs fail at some point in the clinical trial process."

The team, led by researchers from the University of Toronto-Mississauga, looked through industry-sponsored drug development programs registered on clinicaltrials.gov from 1998 to 2012 to see how often drugs actually reached the market overall. They also looked at trials involving HER2-positive patients (a validated biomarker) or patients who had either failed or had been exposed to the chemotherapies anthracycline or taxane, which do not use a biomarker.

"We found that only 14% of drugs that undergo human testing for advanced and metastatic breast cancer are eventually approved," says Parker. "This is worse than the average for the industry as a whole."

The success rate for new drugs for patients exposed to anthracycline or taxane was only 15%, while in HER2-positive patients it rose to 23%. Looking at the cost of clinical trials, this was $199 million in HER2-positive breast cancer patients, compared with $274 million for the anthracycline or taxane patients. This translates to the validated biomarker HER2 reducing clinical risk nearly 50%, and cutting costs 27% in advanced and metastatic breast cancer.

These findings only reflect the effect of one biomarker, HER2, and need to be repeated looking at studies that combine a novel drug with a novel biomarker not yet recognized by the FDA, which may cut, or even increase clinical trial risk, and these studies are ongoing. However, Parker sees the results as encouraging.

"This is the first study that has made a systematic comparison between patients with and without a biomarker," he says. "It provides us with concrete initial evidence that the use of a biomarker can help improve clinical trial success rates in breast cancer."

- read the press release
- see the abstract