By Bill Berkrot
(Reuters) - An experimental Roche Holding AG drug, added to standard therapy, led to a far higher rate of remission and helped patients with an advanced, aggressive blood cancer live significantly longer than the standard treatment alone, according to data from a mid-stage trial released at a medical meeting on Sunday.
In the trial of 80 patients with diffuse large B-cell lymphoma (DLBCL) whose disease had progressed despite several treatment regimens, the addition of Roche's polatuzumab vedotin raised the complete response rate to 40 percent. That compared with 15 percent who achieved a complete response with just the standard drugs - Roche's Rituxan and Teva's Treanda chemotherapy. Complete response indicates no detectable signs of cancer.
There was a 65-percent reduction of risk of death with polatuzumab, researchers reported at the American Society of Hematology meeting in Atlanta. Median overall survival was 11.8 months for the polatuzumab combination versus 4.7 months for patients who received standard therapy.
"These results exceeded our expectations both for the complete response rate, because this is a heavily pre-treated population, and also that we were able to detect an overall survival benefit of this magnitude," said Sandra Horning, Roche's chief medical officer and head of product development.
Roche needs new cancer drugs as it begins to face competition from cheaper biosimilar versions of its longtime blockbuster oncology medicines Avastin and Herceptin.
Polatuzumab is a newer type of medicine called antibody drug conjugates designed to link therapeutic antibodies to cancer cell-killing agents while minimizing the effect on normal cells.
Polatuzumab, which targets a specific protein expressed in the majority of B-cell lymphomas, has received breakthrough therapy designation from the U.S. Food and Drug Administration the priority medicines tag from European regulators, indicating that it is widely viewed as a potentially important advance.
It is also being tested in combination with other newer Roche medicines.
Average duration of response improved from 3.7 months with the standard therapy to 8.8 months with the three-drug combination in the Phase II study.
No unexpected safety signals were observed with the addition of polatuzumab, the company said.
DLBCL is a fast growing and the most common form of non-Hodgkin’s lymphoma.
(Reporting by Bill Berkrot; Editing by Nick Zieminski)