New drugs could transform cancer treatment

PARP inhibitors appear to destroy disease, small but stunning study shows

From the website: http://today.msnbc.msn.com/id/31512315/ns/health-womens_health/#storyContinued

Commentary

By Robert Bazell

Chief science and health correspondent

NBC News

updated 3:13 p.m. CT, Wed., June 24, 2009

Robert Bazell Chief science and health correspondent • Profile • E-mail

Just-released research about a new class of drugs called “PARP inhibitors” is the most exciting development in cancer research in a decade or more. In just a few years it could save thousands of lives.

In the longer term, the drugs could represent a transformational approach to understanding and treating several forms of the disease.

All this enthusiasm is based on a small report published today in the New England Journal of Medicine. It focuses on one clinical trial in its earliest stage in 60 patients with breast, ovarian and prostate cancer. Some — but not all — of the patients whose cancers seemed hopeless saw them shrink drastically or disappear. Many avoided the typical side effects — nausea, hair loss — associated with cancer treatment.

Of course, as with any good science, it is not just that one report that generates such excitement. The new research builds on many years of solid basic science and on other clinical trials that are either completed or in progress, which appear to show similarly dramatic reduction of certain breast, ovarian and prostate cancers.

The story of PARP inhibitors began in the early 1990s, when some scientists realized that breast cancer ran in certain families, and that some of the women in those families had an extraordinarily high — as much as a 90 percent lifetime risk — of getting the disease. There was a frantic and well-publicized hunt for the “breast cancer gene.” The hope was that finding the gene could provide crucial information about the cause of breast cancer and how to treat it.

BRCA1, BRCA2 raise risk for breast cancer
In September 1994, scientists from a company called Myriad Genetics and government researchers simultaneously won the race. It turned out there were two genes called BRCA1 and BRCA2. As they studied the genes, the researchers learned that they account for between 5 and 10 percent of all breast cancers, as well as a similar percentage of ovarian cancers and prostate cancers in men who are born with the mutated gene.

The immediate result of the gene discovery was that families and individuals at high risk could find out when they were affected. That continues to this day. But for those at risk, the treatment options are limited: surgical removal or close monitoring of the organs that might become cancerous.