2012 Gastrointestinal Cancers Symposium
SAN FRANCISCO — The investigational drug regorafenib extended survival in patients with treatment-refractory metastatic colorectal cancer by 1.4 months, according to data presented at the 2012 ASCO Gastrointestinal Cancers Symposium.
“When standard therapies for patients with metastatic colorectal cancer stop working, and the cancer continues to worsen, most patients only survive a few months,” researcher Axel Grothey, MD, professor of oncology at the Mayo Clinic in Rochester, Minn., said in a press release. “So it’s exciting that this is the first time an agent has shown a statistically significant OS benefit, in some cases adding many more months of life, in these patients in a randomized phase 3 study.”
Researchers enrolled 760 patients from 105 treatment centers who exhibited metastatic colorectal cancer and progression during or less than 3 months after their last standard treatment. In the trial, patients were randomly assigned regorafenib (Bayer HealthCare Pharmaceuticals) or a placebo, in conjunction with best supportive care — including antibiotics, analgesics, radiation therapy for pain from bone metastases and corticosteroids. Patients continued in their randomized treatments until progression, death or unacceptable toxicity was demonstrated.
Preliminary analysis of the study results revealed an estimated HR for OS was 0.773 (95% CI, 0.635-0.941). The researchers found that the median OS was 6.4 months (95% CI, 5.9-7.3) for regorafenib and 5 months (95% CI, 4.4-5.8) for placebo, indicating a 29% increase in OS. The estimated HR for PFS was 0.493 (95% CI, 0.418-0.581), with regorafenib exhibiting a median PFS of 1.9 months (95% CI, 1.88-2.17) and the placebo showing a median PFS of 1.7 months (95% CI, 1.68-1.74).
The researchers said regorafenib appears more effective in stabilizing disease and delaying tumor growth, rather than in shrinking tumors, particularly in patients who have failed all approved standard therapies. Adverse effects observed in the regorafenib arm of the study included hand-foot skin reaction, fatigue, diarrhea, hyperbilirubinemia and hypertension.
“It is important to reiterate that the positive findings [of this study] were noted in a population who had already progressed or failed conventional therapies,” said Morton S. Kahlenberg, MD, a member of the 2012 Gastrointestinal Cancers Symposium News Planning Team. “This lays the groundwork for further study to look at an agent to possibly become a component of standard therapies for colon and rectal cancer in the future.”
For more information:
- Grothey A. Abstract # LBA385. Presented at: ASCO Gastrointestinal Cancers Symposium; Jan. 19-21, 2012; San Francisco.
Disclosure: Researchers report consulting and advisory financial support from Amgen, AstraZeneca, Bayer, Celgene, Chugai Pharma, Merck, Merck Serono, Roche, Sanofi-Aventis and Yakult.