Novel therapy slows tumor growth in 85% of advanced breast cancer patients: Study

March 26, 2016

The international study enrolled 54 patients in two groups. The first group of 27 women received 400 mg oral olaparib twice daily and the second group of 27 patients received 100 mg oral olaparib twice daily. The higher dose appeared to have more activity against the disease, with one patient (4%) having a complete resolution of her tumor and ten (37%) showing substantial tumor shrinkage. Another 12 (44%) women had stable disease or some tumor shrinkage, but not enough to be considered a partial response by standard criteria. In the low dose group, six (22%) patients showed substantial shrinkage and 12 (44%) had some tumor shrinkage or stable disease.

Although the results look good thus far, Domchek says more clinical trials will be necessary before olaparib or other PARP inhibitors in development will be ready for use in regular practice. "It is important for patients to join those clinical trials because we need to determine how best to use these drugs, on their own or in combination with other agents," she said. "And we need to establish definitively that they are better than other drugs."

The PARP inhibitors are a transition in the field of cancer drug development. "This is a different way of looking at cancer therapeutics," Domchek says. "In oncology, this is really one of the first times that we've seen drugs being developed on the basis of inherited susceptibility - and that may open up a whole new avenue of drug development."

SOURCE University of Pennsylvania School of Medicine