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Journal of Clinical Oncology, Vol 24, No 24 (August 20), 2006: pp. 3946-3952 © 2006 American Society of Clinical Oncology. DOI: 10.1200/JCO.2005.05.1490 Randomized Phase III Trial of Gemcitabine Plus Cisplatin Compared With Gemcitabine Alone in Advanced Pancreatic Cancer
From the Medizinische Klinik und Poliklinik III, Klinikum Grosshadern; Krankenhaus Bogenhausen; Klinikum Neuperlach München; Krankenhaus München-Harlaching; Klinik für Strahlentherapie, Klinikum Grosshadern, Munich; Klinikum Chemnitz; Universitätsklinik Kiel, Kiel; Evangelisches Krankenhaus Dinslaken, Dinslaken; Klinikum Nürnberg Nord, Nürnberg; Klinikum Darmstadt, Darmstadt; Evangelisches Krankenhaus Düsseldorf, Düsseldorf; Medizinische Fakultät der TU Dresden, Dresden; Mutterhaus der Borromäerinnen Trier, Trier; Onkologische Praxis Augsburg, Augsburg; Onkologische Praxis Landshut; Klinikum Landshut, Landshut; Medizinische Universität zu Lübeck, Lübeck; Medizinische Klinik II, Universität Würzburg, Würzberg; Wissenchaftlicher Service Pharma (WiSP), Langenfeld, Germany Address reprint requests to Volker Heinemann, MD, PhD, Medical Clinic III, Klinikum Grosshadern, Marchioninistrasse 15, 81377 Munich, Germany; e-mail: Volker.Heinemann{at}med.uni-muenchen.de
PURPOSE: To compare the effectiveness and tolerability of gemcitabine plus cisplatin with single-agent gemcitabine as first-line chemotherapy for locally advanced or metastatic pancreatic cancer. PATIENTS AND METHODS: Patients with advanced adenocarcinoma of the pancreas were randomly assigned to receive either gemcitabine 1,000 mg/m2 and cisplatin 50 mg/m2 given on days 1 and 15 of a 4-week cycle (GemCis arm) or gemcitabine alone at a dose of 1,000 mg/m2 on days 1, 8, and 15 of a 4-week regimen (Gem arm). The primary end point was overall survival; secondary end points were progression-free survival, response rate, safety, and quality of life. RESULTS: One hundred ninety-five patients were enrolled and showed baseline characteristics well balanced between treatment arms. Combination treatment in the GemCis arm was associated with a prolonged median progression-free survival (5.3 months v 3.1 months; hazard ratio [HR] = 0.75; P = .053). Also, median overall survival was superior for patients treated in the GemCis arm as compared with the Gem arm (7.5 v 6.0 months), an advantage which did not, however, reach statistical significance (HR = 0.80; P = .15). Tumor response rates were comparable between treatment arms (10.2% v 8.2%). The rate of stable disease was, however, greater in the combination arm (60.2% v 40.2%; P < .001). Grade 3 to 4 hematologic toxicity did not exceed 15% in both treatment arms. CONCLUSION: These results support the efficacy and safety of an every-2-weeks treatment with gemcitabine plus cisplatin. Median overall survival and progression-free survival were more favorable in the combination arm as compared with gemcitabine alone, although the difference did not attain statistical significance.
Cancer of the exocrine pancreas remains a fatal disease for most patients. Because of its predominantly late diagnosis, most patients present with advanced disease.1,2 Without effective treatment, these patients have a median survival of 3 to 4 months. Systemic chemotherapy with single-agent gemcitabine has evolved as a moderately active standard of care for treatment of locally advanced and metastatic pancreatic cancer.3,4 Its wide acceptance is based not only on good tolerability but also on its potential to improve clinical benefit response.5,6 In patients receiving gemcitabine, Karnofsky performance status (KPS) and stage of disease have been identified as important prognostic factors for treatment outcome.7 In an effort to improve therapeutic efficacy, numerous clinical studies have investigated gemcitabine (Gem) -based combination regimens. Some trials showed an improvement of overall response rates (ORR) and progression-free survival (PFS). However, a significant prolongation of overall survival (OS) has not been demonstrated when Gem was combined with platinum analogs,8,9 antimetabolites,10-13 or topoisomerase inhibitors.14,15 This may be explained by the notably low chemosensitivity of pancreatic cancer, but it may also relate to the fact that knowledge on adequate patient selection for different treatment strategies is limited so far. The rationale for a combined use of Gem and cisplatin (Cis) is based on the preclinical evidence that Gem not only increases Cis-induced DNA cross links, but also effectively inhibits their repair. Synergistic cytotoxicity observed in vitro clearly relates to this drug interaction.16-19 In pancreatic cancer, several clinical studies suggest that the combination of Gem and Cis is active and may improve ORR, PFS, and OS.8,20-22 The present trial compares a biweekly application of Gem and Cis to a regimen where single-agent Gem was administered weekly for 3 weeks in a 4-week regimen.
Patient Population This trial included patients with pathologically confirmed, locally advanced or metastatic pancreatic cancer (adenocarcinoma or poorly differentiated) not amenable to surgical resection. Tumor lesions had to be bidimensionally measurable with a minimum size of 1 cm x 1 cm. Prior chemotherapy was not allowed. Prior radiotherapy was permitted only when the irradiated lesion was not the target lesion. Other eligibility criteria included age at least 18 years, life expectancy at least 12 weeks, and KPS at least 70%. Patients must have had adequate bone marrow and organ function tests.
Patient Assignment
Treatment
Efficacy Evaluation
Safety Evaluation
Quality-of-Life Evaluation
Statistical Methods
Patient Characteristics Between December 1997 and January 2002, a total of 195 patients (intent-to-treat population) were enrolled onto the study from 34 different centers (see Online Only Appendix). Five patients (three in the GemCis arm and two in the Gem arm) did not receive treatment per protocol and further follow-up was omitted. According to the protocol, 190 patients (95 in the GemCis arm and 95 in the Gem arm) were assessable and were included into the population of analyzable patients. Median follow-up for patients treated in the GemCis arm was 7.4 months (range, 0.2 to 48.6 months), whereas it was 6.0 months (range, 0.3 to 48.5 months) for those in the Gem arm. At the time of final analysis, 92.3% of patients had died. Patient characteristics are shown in Table 1.
Treatment Administration Median duration of treatment was longer in the GemCis arm compared with the Gem arm (4.1 v 3.3 months). Accordingly, patients in the combination arm received a median of 4 cycles (range, 0 to 20) of chemotherapy as compared to a median of 3 cycles documented for the single-agent arm (range, 0 to 15). Adherence to the treatment protocol was comparable in both treatment arms. In the GemCis arm, 1,013 cycles were analyzed; dose reductions were performed in 5.3%, dose delays in 2.7%, and omissions of doses in 1.5% of cycles. In the Gem arm, a total of 772 cycles were applied; dose reductions, delays, and omissions were reported in 7.5%, 4.6%, and 2.3%, respectively. The analysis of relative dose-intensity during a range of 1 to 10 treatment cycles indicated that more than 90% of chemotherapy doses were applied as scheduled with no significant difference between treatment arms. The median relative dose-intensity was 93% to 99% for Gem and 92% to 99% for Cis in the GemCis arm, whereas it was 92% to 97% in the Gem arm.
Second-Line Therapy
Safety Results
Efficacy Results A detailed analysis of treatment efficacy is shown in Tables 3 and 4.
Response rate. Response to treatment was evaluated by intent-to-treat for the whole population of randomly assigned patients. The rate of partial responses was comparable between treatment arms amounting to 10.2% (95% CI, 4.2 to 16.2) in the GemCis arm and 8.2% (95% CI, 2.8 to 13.7) in the Gem arm. A significant improvement was, however, observed in the stable disease rate when patients received GemCis (60.2%; 95% CI, 50.5% to 69.9%) as compared with Gem (40.2%; 95% CI, 30.5% to 50%). Median duration of response for GemCis and Gem was 7.3 months (range, 2.0 to 10.8 months) versus 7.8 months (range, 2.1 to 11.4 months), and median duration of stable disease was 6.0 months (range, 1.1 to 28 months) versus 4.4 months (range, 1.2 to 37.4 months), respectively. Disease control rate (DCR) summarizes partial response and stable disease, thereby accounting for the overall benefit from treatment. DCR was significantly (P < .001) greater in the GemCis arm (70.4%, 95% CI, 61.4% to 79.5%) as compared with the Gem arm (DCR = 48.5%, 95% CI, 38.5% to 58.4%). The relevance of this observation is underlined by nonoverlapping CIs and is reflected by a 2.4-fold lower rate of progressive disease (PD) in the GemCis arm. PFS. GemCis caused a superior PFS (5.3 v 3.1 months; P = .053) compared with Gem (Fig 1). In a post hoc subset analysis, the superiority of GemCis was even more pronounced in locally advanced disease (8.6 v 3.2 months; P = .0053), whereas only a moderate advantage was detected in patients with metastatic disease (4.2 v 3.1 months; P = .31). A further subset analysis revealed that GemCis was superior to Gem in patients with a KPS of 90% to 100% (7.7 v 2.8 months; P = .013), whereas no advantage was observed in patients with a KPS of 70% to 80%.
Overall Survival Although GemCis was superior to Gem, inducing a 25% increase of median survival (7.5 v 6.0 months), the study was not sufficiently powered to reach statistical significance (hazard ratio [HR] = 0.80, P = .15; Fig 2). In patients with metastatic disease only, median survival was markedly prolonged (7.2 v 4.7 months). This was not the case in locally advanced pancreatic cancer (10.3 v 10.4 months). In patients with KPS 90% to 100%, GemCis induced an increase of median survival time from 6.9 to 10.7 months (P = .051), but no improvement of survival (4.9 v 4.8 months) was noted in patients with KPS 70% to 80%.
Uni- and Multivariate Analysis of Prognostic Factors In the univariate analysis, stage of disease (HR = 1.55, P = .0048) and KPS (HR = 0.52, P = .0006) had a significant prognostic impact on survival, whereas treatment arm, age, sex, and tumor grading did not. A subsequently performed multivariate analysis (Table 5) confirmed stage of disease (HR = 1.65; P = .022) and KPS (HR = 0.59; P = .0051) as independent determinants of overall survival.
QOL Results QOL was assessed at treatment start and was followed for up to six cycles of therapy (Table 6). The analysis of the five-item QOL index23 suggests a trend for an improvement during the first two cycles of chemotherapy. Thereafter, the QOL index remained stable and, at no time point, showed a significant difference between treatment arms. Pain intensity as rated by a visual analog scale decreased during the first two cycles of chemotherapy, where a plateau was reached. No significant difference was apparent between the treatment arms.
The optimal regimen for the combined use of gemcitabine and cisplatin has not been defined. In several clinical studies, cisplatin has been applied once every 3 to 4 weeks, biweekly, or even weekly. In a previous phase II trial performed in the first-line treatment of advanced pancreatic cancer, Gem (1,000 mg/m2) was administered on days 1, 8, and 15 of a 4-week schedule, whereas cisplatin (50 mg/m2) was administered on days 1 and 15.21 Median survival in this trial was 8.2 months. Although tolerability of this regimen was deemed acceptable, hematotoxicity with grade 3 to 4 neutropenia (29% of patients) and thrombocytopenia (13% of patients) were the main reasons for dose reductions or omissions documented in more than 30% of cycles. To improve on feasibility and to ensure the application of cisplatin and gemcitabine on day 15, the treatment schedule was modified, and the application of gemcitabine on day 8 was generally omitted. In the present trial, the experimental arm consisted of Gem and cisplatin both administered on days 1 and 15 of a 4-week regimen, whereas in the comparator regimen, patients received single-agent Gem on days 1, 8, and 15 every 4 weeks. The more intensive treatment in the combination arm was therefore in part balanced by a more frequent drug application in the control arm. According to the protocol, the relative dose-intensity of Gem for the Gem versus the GemCis arm was 1.5. In the randomized trial, tolerability was acceptable in both treatment arms, which is reflected by a high relative dose-intensity (> 90%). In view of the low number of reduced, delayed, or omitted doses (< 10%, respectively) the presently used biweekly regimen of Gem and cisplatin showed a better tolerability than the previously used schedule (Gem administered on days 1, 8, 15 plus cisplatin administered on days 1 and 15 every 4 weeks).21 Compared with the GemOx regimen (fixeddose rate Gem plus oxaliplatin) previously reported by Louvet et al,9 toxicity associated with GemCis was comparable with the exception of nausea and vomiting observed at a higher rate in the cisplatin-based regimen and peripheral sensory neuropathy occurring more frequently with oxaliplatin-based therapy. QOL has gained acceptance as a surrogate end point of treatment efficacy due to the trials reported by Burris and Rothenberg.5,6 Their work on clinical benefit response as a composite parameter of pain, performance status, and weight not only demonstrated that Gem was superior over bolus fluorouracil, but also showed that this end point related to a significantly improved survival. Using the five-item QOL index described by Spitzer al,23 it could be shown in this trial that treatment with GemCis, despite a higher overall incidence of adverse effects, did not impair QOL when compared with treatment with Gem alone. A trend toward an improved QOL score was equally observed in both treatment arms during the initial two cycles of therapy. It is a general notion that response evaluation by imaging is difficult in pancreatic cancer and may be limited by desmoplastic and inflammatory reactions of the tumor. For this reason, DCR may give a more reliable reflection of drug efficacy than ORR alone. Previous reports had indicated that Gem induced a DCR of 42% to 44%,5,8 whereas the combination of Gem and Cis consistently increased DCR to a range of 55% to 68%.8,20-22 These data are essentially confirmed by the present randomized trial where in the intent-to-treat analysis a DCR of 70.4% was reached in the GemCis arm, whereas DCR in the Gem arm was 48.5%. From the viewpoint of preventing initial PD, GemCis was 2.4-fold more effective than Gem (PD = 18.4% v 43.3%; P < .001). Patients treated in the GemCis arm showed a marked (71%) prolongation of PFS compared with Gem alone (5.3 v 3.1 months). Although this improvement suggests a distinctly greater efficacy of the GemCis combination, it failed to reach the level of significance when all patients were evaluated. A significantly superior effect of the GemCis regimen was, however, demonstrated in a post hoc analysis of patients with locally advanced pancreatic cancer (8.6 v 3.2 months; P = .0053). So far, there is no good explanation as to why the PFS advantage observed in locally advanced disease did not translate into a corresponding survival benefit (10.3 v 10.4 months). Comparable results have also been reported by Louvet et al9; their GemOx regimen improved PFS but had no effect on survival compared with standard-dose Gem. A further hypothesis-generating subset analysis suggests that patients with a good KPS (90% to 100%) may be those who benefit most from a relevant prolongation of PFS in the GemCis as compared with the Gem arm (7.7 v 2.8 months; HR = 0.54; P = .013). The primary end point of this trial was OS. The 25% (7.5 v 6.0 months) increase of OS induced by GemCis compares with a 50% (7.5 v 5.0 months) increase observed by the Italian group8 and also relates to the 27% (9.0 v 7.1 month) increase reported for the GemOx regimen by the French/Italian group.9 Although it appears that platinum-based regimens consistently prolonged survival, none of the trials so far showed a statistically significant superiority of the combination. Most likely, this is a result of the underpowered design of the trials. In view of the consistency of results, the question of whether the outcome of the aforementioned trials should rightfully be considered a negative one needs to be asked. Not only a meta-analysis of the available studies, but also the upcoming data from an Eastern Cooperative Oncology Group (ECOG) trial comparing GemOx with fixed-dose rate and standard-dose Gem may help to clarify this topic. The interpretation of trial results may also depend on subgroups of patients with different prognosis. A multivariate analysis performed in this trial suggests that not only stage of disease, but also performance status are independent prognostic factors for survival. Moreover, evidence from a post hoc analysis leads to the hypothesis that specifically patients with a good KPS (90% to 100%) will draw the greatest benefit from combination therapy with Gem and Cis, whereas those patients with a worse performance status should receive single-agent therapy with Gem. Also, second-line therapy evolves as an important confounder of survival analysis. So far, second-line therapy has not been established in pancreatic cancer. Although in this trial, centers were encouraged to allow cross-over when treatment failed in one arm, only 16% of patients actually received second-line therapy, which did not have an impact on outcome. By comparison, already 55% of patients received further treatment in the French/Italian trial.9 In conclusion, the combination of Gem with Cis has significantly improved disease control rate and induced an improved, but not statistically significant, prolongation of PFS and OS. The perspective for further development in pancreatic cancer therapy is set by the development of targeted agents. First results indicate the superiority of gemcitabine in combination with erlotinib.24 Future trials must define those subgroups of patients who will benefit most from targeted therapy alone or in conjunction with single-agent or combination chemotherapy.
We thank all the following investigators for their contribution to this randomized multicenter trial: Prof Aul (Würzburg), Dr Berchem (Freiburg), D. Bosse (München), Prof Clemens (Trier), Dr Fleckenstein (Munich), Dr Frick (Regensburg), Dr Gesierich (München), Prof Gieseler (Kiel), Dr Gonnermann (Dinslaken), Dr Haag (Dresden), Dr Harich (Bad Trissl), Dr Heinrich (Augsburg), Dr Hinke (Langenfeld), Dr Hoffmann (Norderstedt), Prof Holstege (Landshut), Dr Hurtz (Halle), Dr Jechart (Augsburg), Dr Junhold (Hof), Dr Krödel (Fulda), Prof Neuhaus (Düsseldorf), PD Dr Quietzsch (Chemnitz), Dr Rost (Darmstadt), Prof Schalhorn (München), Prof Schepp (Munich), Dr Schlotzauer (Hagen), Dr Schmohl (Munich), Dr Schönekäs (Nürnberg), Dr Schulz (Garmisch-Partenkirchen), M. Szymala (Munich), Dr Uthgenannt (Lübeck), Dr Vehling-Kaiser (Landshut), Dr Wilkowski (Munich), and M. Wolff (Munich).
Although all authors completed the disclosure declaration, the following authors or their immediate family members indicated a financial interest. No conflict exists for drugs or devices used in a study if they are not being evaluated as part of the investigation. For a detailed description of the disclosure categories, or for more information about ASCOs conflict of interest policy, please refer to the Author Disclosure Declaration and the Disclosures of Potential Conflicts of Interest section in Information for Contributors.
Dollar Amount Codes (A) < $10,000 (B) $10,000-99,999 (C)
Authors' disclosures of potential conflicts of interest and author contributions are found at the end of this article.
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Riess A, Helm M, Niedergethmann, et al : A randomised, prospective, multicenter, phase III trial of gemcitabine, 5-fluorouracil, folinic acid versus gemcitabine alone in patients with advanced pancreatic cancer. J Clin Oncol 24: 310s, 2005 (suppl; abstr LBA4009) 12. Herrmann R, Bodoky G, Ruhstaller T, et al: Gemcitabine plus capecitabine versus gemcitabine alone in locally advanced or metastatic pancreatic cancer: A randomized phase III study of the Swiss Group for Clinical Cancer Res (SAKK) and the Central European Cooperative Group (CECOG). J Clin Oncol 24: 310s, 2005 (suppl; abstr LBA4010) 13. Richards DA, Kindler HL, Oettle H, et al: A randomized phase III study comparing gemcitabine + pemetrexed versus gemcitabine in patients with locally advanced and metastatic pancreas cancer. J Clin Oncol 23: 315s, 2004 (suppl; abstr 4007) 14. 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Philip PA, Zalupski MM, Vaitkevicius VK, et al: Phase II study of gemcitabine and cisplatin in the treatment of patients with advanced pancreatic carcinoma. Cancer 92: 569-577, 2001[CrossRef][Medline] 23. Spitzer WO, Dobson AJ, Hall J, et al: Measuring the quality of life of cancer patients: A concise QL-index for use by physicians. J Chron Dis 34: 585-597, 1981[CrossRef][Medline] 24. Moore MJ, Goldstein D, Hamm J, et al: Erlotinib plus gemcitabine compared to gemcitabine alone in patients with advanced pancreatic cancer: A phase III trial of the National Cancer Institute of Canada Clinical Trials Group [NCIC-CTG]. J Clin Oncol 23: 1s, 2005 (suppl; abstr 1)[CrossRef][Medline] Submitted January 18, 2006; accepted June 20, 2006. Related Correspondence
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