In the Italian phase II noncomparative PANDA trial reported in the Journal of Clinical Oncology, Lonardi et al found that regimens adding panitumumab to modified FOLFOX (fluorouracil, leucovorin, and oxaliplatin; mFOLFOX) and to fluorouracil/leucovorin were active in the first-line treatment of elderly patients with RAS/BRAF wild-type metastatic colorectal cancer.
Study Details
In the multicenter open-label trial, 183 patients aged ≥ 70 years were randomly assigned between July 2016 and April 2019 to receive panitumumab at 6 mg/kg every 2 weeks with either mFOLFOX (n = 91) or fluorouracil/leucovorin (n = 92) for up to 12 cycles followed by panitumumab maintenance. The primary endpoint was progression-free survival. The null hypothesis was median progression-free survival of 6 months.
Key Findings
At a median follow-up of 50.0 months (interquartile range = 45.6–56.4 months), median progression-free survival was 9.6 months (90% confidence interval [CI] = 8.8–10.9 months) in the panitumumab/mFOLFOX group and 9.0 months (90% CI = 7.7–9.9 months) in the panitumumab/fluorouracil/leucovorin group (both P < .001 vs null hypothesis).
Objective response rates were 69% (95% CI = 59%–78%) in the panitumumab/mFOLFOX group and 52% (95% CI = 42%–63%) in the panitumumab/fluorouracil/leucovorin group, with complete response in 4% and 5%, respectively. Median overall survival was 23.5 months (95% CI = 18.9–28.7 months) and 22.0 months (95% CI = 16.9–29.5 months).
Grade > 2 chemotherapy-related adverse events occurred in 60% of the panitumumab/mFOLFOX group and 37% of the panitumumab/fluorouracil/leucovorin group. The most common grade 3 or 4 adverse events in the panitumumab/mFOLFOX group were rash (25% vs 24% in panitumumab/fluorouracil/leucovorin group), diarrhea (16% vs 1%), stomatitis (10% vs 4%), neutropenia (10% vs 1%), and fatigue (8% vs 4%).
The investigators concluded, “Both mFOLFOX and fluorouracil/leucovorin [plus panitumumab] are reasonable options as initial therapy of elderly patients with RAS/BRAF wild-type metastatic colorectal cancer. Fluorouracil/leucovorin [plus panitumumab] is associated with a better safety profile.”
Sara Lonardi, MD, of the Department of Oncology, Veneto Institute of Oncology IOV-IRCCS, Padova, is the corresponding author for the Journal of Clinical Oncology article.
Disclosure: The study was supported by Amgen. For full disclosures of the study authors, visit ascopubs.org.