Panitumumab is a fully human antibody developed against the human epidermal growth factor receptor receptor (EGFR/HER-1), which is overexpressed in > or = 75% of patients with colorectal cancer. As a ...fully human antibody, panitumumab can be administered without any premedication and has the promise of decreased infusion reactions. Clinical studies have demonstrated that panitumumab has significant activity as a single agent and improves progression-free survival when compared with best supportive care. It can also be safely combined with standard cytotoxic chemotherapy. Ongoing studies are being performed to determine if the addition of panitumumab to first-line standard treatment for metastatic colorectal cancer will improve the progression-free and overall survival of these patients.
Sunitinib is an oral inhibitor of tyrosine kinase receptors implicated in tumor proliferation, angiogenesis, and metastasis. In this randomized, multicenter, open-label Phase IIb study, sunitinib ...plus mFOLFOX6 (oxaliplatin plus leucovorin plus 5-fluorouracil) was compared with bevacizumab plus mFOLFOX6 as first-line therapy in patients with metastatic colorectal cancer.
Patients were stratified by performance status, baseline lactate dehydrogenase level, and prior adjuvant treatment, and randomized 1:1 to receive sunitinib 37.5 mg/day for 4 weeks on and 2 weeks off plus mFOLFOX6 every 2 weeks or bevacizumab 5 mg/kg every 2 weeks plus mFOLFOX6 every 2 weeks. The primary endpoint was progression-free survival. Secondary endpoints included objective response rate, overall survival, safety, and quality of life.
Enrollment was closed early following accrual of 191 patients, based on an interim analysis showing an inferior trend in the primary progression-free survival efficacy endpoint for sunitinib. Ninety-six patients were randomized to sunitinib plus mFOLFOX6 and 95 to bevacizumab plus mFOLFOX6. Median progression-free survival was 9.3 months and 15.4 months, respectively, but the objective response rate was similar between the study arms. Median overall survival was 23.7 months and 34.1 months, respectively. Dose reductions and interruptions were more common with sunitinib. Hematologic toxicity was more common in the sunitinib arm.
While the results of the sunitinib arm are comparable with those of previously reported FOLFOX combinations, the sunitinib-based combination was associated with more toxicity than that observed with bevacizumab and mFOLFOX6. The bevacizumab arm had an unexpectedly good outcome, and was much better than that seen in the Phase III trials. Combination therapy with sunitinib plus mFOLFOX6 is not recommended for patients with metastatic colorectal cancer.
Abstract Objectives Optimal treatment strategies in frail and/or elderly patients with metastatic colorectal cancer have not been well defined. Using data from a prospective, phase II study of ...elderly patients with metastatic colorectal cancer treated with bevacizumab and capecitabine, we explored the differences in functional measure and quality of life (QoL) between patients with ECOG performance status (PS) 1 and 2. Materials and Methods Geriatric functional measures included patient reported limitations in ADLs and IADLs, ECOG PS, 3-item recall, hearing acuity, and the “Get up and Go” test. QoL was assessed by means of the FACT-C questionnaire and the EQ-5D questionnaire. The prognostic impact of baseline characteristics on survival was studied using univariate Cox regression analysis. Results The majority (62%) of the 45 patients had an ECOG PS of 2. The ECOG PS 2 group had more limitations in IADLs, lower baseline QoL, and a lower patient-rated health score. For all participants, QoL significantly improved from baseline to the start of cycle 2 (FACT-C: 99.9 vs. 105.4, p = 0.01) and did not deteriorate when baseline scores were compared to when participants went off study (FACT-C: 99.9 vs. 98.6, p = 0.59). In the Cox-regression analysis, a positive “Get up and Go” test was prognostic for improved survival (HR = 0.31, p = 0.01). Conclusion There is significant heterogeneity in functional measures and quality of life among elderly patients with metastatic colorectal cancer with ECOG PS 1 and 2. The “Get up and Go” test may be a useful prognostic indicator for survival in this population.
A large number of new drugs have been approved over the past 10 years for the treatment of both common and rare gastrointestinal malignancies. Many other agents, however, have failed at a great cost ...of financial and patient resources. Drug development must identify potentially active compounds and reveal the most effective and least toxic manner and population in which to administer compounds. Pharmaceutical companies must show therapeutic efficacy and achieve regulatory approval as well as success in the marketplace to recoup their investment. It is worth examining successful examples of drug development such as imatinib, delayed but eventually successful agents such as oxaliplatin, as well as failures such as SU-5416, and applying those lessons to current and future drug development.
Abstract Objectives This study aims to determine the efficacy and tolerability of capecitabine (CAP) plus bevacizumab (BEV) as treatment for frontline metastatic colorectal cancer (mCRC) in frail ...and/or elderly patients. Materials and Methods This was an open label, multi-site, single arm, phase II study in frontline mCRC. In this study, patients (pts) who were frail (ECOG 2) or older patients with ECOG 1 performance status (PS) received CAP (1000 mg/m2 bid, 14 days of every 21 days) plus BEV (7.5 mg/kg iv once every 21 days). The primary objective was progression free survival (PFS). Secondary objectives were overall response rate (ORR) and toxicity. Results In terms of patients: 50 were enrolled; 5 withdrew consent prior to treatment; 45 were treated, and 41 were evaluable. The mean age was 75.9 (range 54–93) and 62% had an ECOG 2 PS. The median PFS was 6.87 months (95% CI, 5.1–11.5 months) and median overall survival was 12.7 months (95% CI, 6.9–12.7 months). The most common grades 3–4 toxicities were: diarrhea (17.8%), fatigue (13.3%), hand–foot syndrome (13.3%), dehydration (8.9%), hypertension (6.7%) and vomiting (6.7%). Conclusions The results of this trial support the use of CAP plus BEV as first-line treatment for frail/elderly patients with metastatic CRC. The ORR (40%) is comparable to pooled data in elderly on fluorouracil (5-FU) + BEV. The median PFS (7.2 months) in this study is slightly lower than that seen with 5-FU + BEV but this study had a high percentage of ECOG PS 2 patients. Side effects were manageable with no new safety signals.
Panitumumab in colorectal cancer Wainberg, Zev A; Hecht, J Randolph
Expert review of anticancer therapy
7, Issue:
7
Journal Article
Peer reviewed
The combination of chemotherapy and targeted therapies is rapidly becoming the standard of care in the treatment of metastatic colorectal cancer. Panitumumab (formerly ABX-EGF) is a fully human ...antibody developed to target the human epidermal growth factor receptor (EGFR/HER-1), which is expressed in up to 75% of patients with colorectal cancer. As a fully human antibody, panitumumab can be administered without any premedication and few infusion reactions have been reported. It has recently been approved in the USA for the treatment of colorectal cancer as a single agent in the salvage setting. Ongoing studies are being performed to determine whether the addition of panitumumab to standard treatment for metastatic colorectal cancer will improve the survival of these patients.
The pathobiology of precursor lesions leading to invasive pancreatic adenocarcinoma remains a controversial area, but knowledge of the mechanisms of tumorigenesis may lead to possibly earlier ...detection, prevention, and treatment in the future. We hypothesize that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions and are part of a continuous developmental spectrum evolving into ductal adenocarcinoma of the pancreas. To further define this sequence, we studied the immunohistochemical markers HER-2/
neu, K-
ras, and p53 in 15 adenocarcinomas and 15 nonmalignant specimens of the pancreas. The 15 nonmalignant specimens of the pancreas included both normal pancreas and chronic pancreatitis. Overall, HER-2/
neu was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 30, 11 of 20 (55%), 10 of 15 (67%), and 12 of 15 (80%), respectively, with progressive increase in the intensity of staining; p53 was positive in 1 of 30 (3%), 0 of 20, 3 of 15 (20%), and 13 of 15 (80%), respectively, and K-
ras was positive in 1 of 30 (3%), 6 of 20 (30%), 11 of 15 (73%), and 8 of 15% (53%), respectively. These data support the hypothesis that ductal hyperplasia and dysplasia of the pancreas represent precursor lesions, and, in a fashion similar to that in colorectal tumorigenesis, pancreatic cancer seems to accumulate progressive genetic alterations.
PDF
