Sorafenib viable option in treating drug-resistant GIST
2011 Gastrointestinal Cancers Symposium
SAN FRANCISCO — Sorafenib appears to be a viable treatment option for patients with gastrointestinal stromal tumors who are resistant to imatinib and sunitinib.
Results from a phase 2 trial of 38 patients with gastrointestinal stromal tumors (GIST) assigned to the targeted tyrosine kinase inhibitor sorafenib (Nexavar, Bayer) showed that tumors decreased in 13% of patients and were stable in 55% of patients.
“These data demonstrate that sorafenib has definite activity in imatinib- and sunitinib-resistant GIST,” said Nicholas P. Campbell, MD, an oncology fellow at the University of Chicago. “Prolonged disease control is possible in these refractory patients, even in those with primary sunitinib resistance.”
Campbell presented the results during a press conference in advance of the 2011 Gastrointestinal Cancers Symposium.
Six patients in the study were resistant to imatinib (Gleevec, Novartis) and 32 were resistant to both imatinib and sunitinib (Sutent, CPPI CV). Patients — all of whom were diagnosed with unresectable, KIT-expressing GIST — were assigned to 400 mg twice-daily oral sorafenib for 28 days. Patients underwent a median of four cycles of therapy (one-40 cycles), and 61% had at least one dose reduction.
After a median follow-up of 31 months, disease control rate was 68%, median PFS was 5.2 months and median OS was 11.6 months.
Patients in the group that was resistant to imatinib alone were more likely to undergo dose reduction (83% vs. 59%), but the small size of that group likely played a role in the difference.
Campbell said the most common grade-3 adverse events were hand-foot syndrome (45%) and hypertension (21%).
“After failure on imatinib and sunitinib, there are limited therapeutic options,” Campbell said. “There is an urgent need for additional agents to treat patients with imatinib- and sunitinib-refractory GIST, since there are no FDA–approved options for these patients other than resumption of imatinib.” – by Jason Harris
For more information:
- Campbell NP. #4. Presented at: the 2011 Gastrointestinal Cancers Symposium; Jan. 20-22, 2011; San Francisco.
Disclosure: Dr. Campbell has no relevant financial disclosures.
Our patients with metastatic GIST do very well — they live on average at least 4 years after diagnosis. Unfortunately, many patients have limited options at some point during their illness. By understanding the molecular mechanisms behind GIST, we have been able to make great strides in our care of these patients. Over the past 10 years, two medications have been approved for treatment of advanced GIST. This presentation demonstrates that additional treatments may be on the horizon because of our investment into clinical research.
– Jennifer C. Obel, MD,
Assistant Clinical Professor of Medicine, University of Chicago
Disclosure: Dr. Obel has no relevant financial disclosures.
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