Cedars Senai It seems that genetic weakness of particular forms of cancer can help scientists to estimate targeted therapy and effective treatment. An international consortium of scientists claims that an investigational drug, Olaparib, can shrink the size of tumors in women with advanced hereditary ovarian cancer having BRCA gene mutations. It has been revealed that PARP inhibitors are likely to be the new option for patients suffering from this ailment.

Throughout the Phase II ovarian cancer study and another Phase II trial, investigators analyzed the drug’s effectiveness in the treatment of hereditary breast cancer. Both trials seemingly revealed similar levels of response to the genetically-targeted drug in breast and ovarian cancers with BRCA mutations. Usually what happens is that, women with advanced BRCA-mutated ovarian cancer go through various chemotherapy regimens. This makes it very difficult to suggest a precise treatment. Olaparib which is claimed to be a Poly ADP ribose polymerase (PARP) inhibitor represents a ‘targeted therapy’ approach to cancer treatment.

William Audeh, M.D., an oncologist specializing in cancer genetics at Cedars-Sinai’s Samuel Oschin Comprehensive Cancer Institute and first author on the ovarian cancer study said, “These are significant new studies. Olaparib is the first single-agent, non-chemotherapy treatment to show benefit to patients with cancers that result from BRCA1 or BRCA2 gene mutations. Until now, treatments for cancer have been selected based upon where in the body the cancer originated. These two studies suggest that it is the underlying genetic weakness of a cancer, not the organ of origin that is the key to selecting effective therapy.”

Scientists believe these anticancer drugs to intrude with certain pathways included in either cancer growth or survival. The PARP enzyme is apparently considered as a hallmark in DNA repair, including the repair of DNA damage from chemotherapy. Medications preventing this enzyme may aid in cancer cell death and elevate their sensitivity to chemotherapy. The study which was triggered on 57 patients, registered 33 percent of participants with extreme decline in the size of their tumors. In fact in some cases the tumors seemed to have completely disappeared.

Audeh commented, “These PARP inhibitor studies represent a major change in the approach to treating cancer that will be reflected in future clinical trials. While we studied Olaparib’s clinical benefit in patients known to have specific genetic weaknesses in their cancer cells, it is hoped that this drug – and others like it – will be an effective tool to treat the underlying genetic defects found in all types of cancers.”

Comparatively very mild toxicities like nausea, fatigue and anemia were supposedly noted from the medication. Scientists suggest that almost 10 percent of these cases have an inherited mutation in the BRCA 1 or 2 genes that are the type of cases treated in the course of the trial. It was mentioned that at present it is very difficult to ascertain the disease in the early stages itself.

The study is published in a recent issue of Lancet.