FDA Approves New Colon Cancer Drug
Vectibix Follows Chemotherapy for Colorectal Cancer That Has Spread
Drug's Trials continued...
Overall survival was similar for both groups during the 48-week study.
"Almost everyone had progressed by 48 weeks," J. Randolph Hecht, MD, tells WebMD. By "progressed," he means their tumors had worsened.
"But at eight weeks, the first look, 70% of the people had progressed on best supportive care, while only 51% had progressed [with] Vectibix," Hecht says. "That 20% or so difference persisted for awhile. By the time you get to 32 weeks it was not a big difference."
Hecht has conducted U.S. studies of Vectibix, but he wasn't involved in the European trial. He directs the gastrointestinal oncology program at the University of California, Los Angeles.
In addition, tumors shrank in 8% of the patients taking Vectibix. In some cases, those tumors shrank to less than half of their pretreatment size.
"At every time point that you looked at, if you were in the Vectibix arm you were much less likely to have your tumor progress than if you were on the best supportive care arm," Hecht says.
"That's another way of looking at that," says Hecht.
The most serious adverse events in the Vectibix studies included pulmonary fibrosis (the formation of fibrous tissue in the lungs), severe skin rashcomplicated by infections, infusion reactions, abdominal pain, nausea, vomiting, and constipation.
The most common adverse events associated with the drug included skin rash, fatigue, abdominal pain, nausea, and diarrhea.
Vectibix is made by Amgen, Inc. The drug company has committed to conduct a postmarketing trial to show whether Vectibix improves patients' survival in patients with fewer prior chemotherapies.