Final results from PRIME: randomized phase III study of panitumumab with FOLFOX4 for first-line treatment of metastatic colorectal cancer

BACKGROUND

The Panitumumab Randomized trial In combination with chemotherapy for Metastatic colorectal cancer to determine Efficacy (PRIME) demonstrated that panitumumab-FOLFOX4 significantly improved progression-free survival (PFS) versus FOLFOX4 as first-line treatment of wild-type (WT) KRAS metastatic colorectal cancer (mCRC), the primary end point of the study.

PATIENTS AND METHODS

Patients were randomized 1:1 to panitumumab 6.0 mg/kg every 2 weeks + FOLFOX4 (arm 1) or FOLFOX4 (arm 2). This prespecified final descriptive analysis of efficacy and safety was planned for 30 months after the last patient was enrolled.

RESULTS

A total of 1183 patients were randomized. Median PFS for WT KRAS mCRC was 10.0 months [95% confidence interval (CI) 9.3-11.4 months] for arm 1 and 8.6 months (95% CI 7.5-9.5 months) for arm 2; hazard ratio (HR) = 0.80; 95% CI 0.67-0.95; P = 0.01. Median overall survival (OS) for WT KRAS mCRC was 23.9 months (95% CI 20.3-27.7 months) for arm 1 and 19.7 months (95% CI 17.6-22.7 months) for arm 2; HR = 0.88; 95% CI 0.73-1.06; P = 0.17 (68% OS events). An exploratory analysis of updated survival (>80% OS events) was carried out which demonstrated improvement in OS; HR = 0.83; 95% CI 0.70-0.98; P = 0.03 for WT KRAS mCRC. The adverse event profile was consistent with the primary analysis.

CONCLUSIONS

In WT KRAS mCRC, PFS was improved, objective response was higher, and there was a trend toward improved OS with panitumumab-FOLFOX4, with significant improvement in OS observed in an updated analysis of survival in patients with WT KRAS mCRC treated with panitumumab + FOLFOX4 versus FOLFOX4 alone (P = 0.03). These data support a positive benefit-risk profile for panitumumab-FOLFOX4 for patients with previously untreated WT KRAS mCRC. KRAS testing is critical to select appropriate patients for treatment with panitumumab.

Combined intensive chemoradiotherapy for organ preservation in patients with resectable and non-resectable oesophageal cancer

From January 1990 to April 1993, 60 oesophageal cancer patients were enrolled in a protocol of non-surgical treatment that consisted of induction chemotherapy followed by concurrent chemoradiotherapy. Induction chemotherapy consisted of cisplatin 40 mg/m2 intravenous bolus days 1, 2, 14, 15; 24 h continuous infusion of 5-fluorouracil (5-FU) 1000 mg/m2 days 1 and 14; leucovorin 20 mg/m2 days 1 and 14 given before and with 5-FU; bleomycin 30 UI days 1 and 14; mitomycin C 10 mg/m2 day 14. Concurrent chemoradiotherapy consisted of 60 Gy (6 weeks) from day 21 and cisplatin 70 mg/m2 days 28, 42 and 56; leucovorin 20 mg/m2 followed by 5-FU 425 mg/m2 days 28, 35, 42, 49 and 56. Complete response occurred in 44 of 55 evaluable patients (80%). The median survival is 32 months; the actuarial survival at 40 months is 35% (CI 18-53). These results appear improved over those reported with surgery or radiation alone, and suggest that organ preservation as a secondary treatment goal should be vigorously investigated.

Treatment of pain and other symptoms in cancer patients: patterns in a North American and a South American hospital

The charts of 200 consecutive patients with cancer pain admitted to a major teaching hospital in Edmonton, Canada (n = 100) and in Buenos Aires, Argentina (n = 100) were reviewed to assess the differences between North American (NA) and South American (SA) facilities in patterns of treatment of pain and other symptoms. Criteria for eligibility and methods were identical in both hospitals. Characteristics of patients (age, sex, primary tumor, reason for admission) and attending staff were similar between both hospitals. Mean daily equivalent doses of parenteral morphine (mg) were 44 +/- 26 and 9 +/- 10 in NA and SA, respectively (p less than 0.001). Patients in NA, received narcotics every 4 hr and on a regular basis more frequently than in SA. The types of narcotics and the use of adjuvant drugs were significantly different between NA and SA. Nonpharmacologic treatments, antiemetics, and laxatives were more frequently used in NA. These results suggest that there are significant differences in symptomatic management of advanced cancer between institutions in NA and SA.

Vinca alkaloid-induced cardiovascular autonomic neuropathy

To determine the incidence of vinca alkaloid (VA)-induced cardiovascular autonomic neuropathy (CAN), neoplastic patients were studied. Thirty-three of them were receiving chemotherapy regimens including VAs, and 30 were receiving chemotherapy without VA and were considered controls. Abnormal variation in blood pressure on standing, heart rate during deep breathing, and heart rate on standing was found in 27 (82%), 16 (48%), and 16 (48%) patients receiving VA versus nine (30%; P less than 0.01), three (10%; P less than 0.05), and one (P less than 0.001) controls, respectively. Of 198 tests performed, 100 were abnormal in patients receiving VA (51%) versus 33 of 180 tests in the controls (18%; P less than 0.001). Although abnormal clinical or electrocardiographic tests for CAN appeared significantly more frequently in patients who received high doses of VA (P less than 0.01), their incidence was not significantly different in patients greater than or equal to 60 years of age, in those who received doxorubicin, or in those who showed abnormal deep tendon reflexes. The consequences of VA-induced CAN might be especially important for potentially curable cancer patients.