The triple-therapy regimen will now be tested nationally in a phase II trial as first-line therapy for advanced non-small cell lung cancer. Angela Davies, assistant professor of hematology/oncology and principal investigator of the phase I trial, will lead the phase II trial as well.
The regimen consists of bortezomib, gemcitabine and carboplatin. Gemcitabine and carboplatin represent an accepted first-line treatment combination for advanced non-small cell lung cancer.
In the small phase I trial, the three drugs were administered on a similar schedule. Out of 12 patients, four had a partial response and seven had stable disease.
In the larger phase II trial, which will enroll 99 patients, the drugs will be given sequentially, with bortezomib following the chemotherapy drugs. Preclinical research at UC Davis Cancer Center suggests that giving bortezomib last may be more effective than giving it first or at the same time.
Bortezomib is a proteasome inhibitor that blocks the signals cancer cells rely on to degrade cellular proteins. The result is a buildup of proteins that hastens cell death.
Bortezomib has been approved by the Food and Drug Administration for the treatment of multiple myeloma, but had not been tested before in non-small cell lung cancer.
"Bortezomib is an exciting therapeutic, and we're encouraged that we've been able to take this promising three-drug combination immediately from phase I to phase II," Davies said.
Of the estimated 175,000 new cases of lung cancer diagnosed in the United States each year, nearly 80 percent are non-small cell lung cancers. New treatments are desperately needed; the overall five-year survival rate for lung cancer remains just 13 percent.
UC Davis Cancer Center ranks first among the 283 institutions comprising the Southwest Oncology Group, one of the world's largest adult clinical trials cooperative groups, in the number of patients enrolled in clinical trials. It is ranked by U.S. News & World Report as one of the nation's top 50 cancer treatment centers.
Claudia Morain can be reached at 530-219-5053 through June 6, 2004 and 916-734-9023 beginning June 7, 2004