Phase III Study Comparing Gemcitabine Phase III Study Comparing Gemcitabine plus Cetuximab versus Gemcitabine in plus Cetuximab versus Gemcitabine in
Patients with Locally Advanced or Patients with Locally Advanced or Metastatic Pancreatic AdenocarcinomaMetastatic Pancreatic Adenocarcinoma
Southwest Oncology Group Protocol S0205Southwest Oncology Group Protocol S0205
PA Philip, J Benedetti, C Fenoglio-Preiser, M Zalupski, H Lenz, E O’Reilly, R Wong,
J Atkins, J Abbruzzese, C Blanke
On behalf of SWOG, CALGB, NCIC, and the CTSU
Systemic Therapy of Systemic Therapy of Pancreas CancerPancreas Cancer
• Gemcitabine-based cytotoxic combination therapies have demonstrated no significant advantage over gemcitabine alone
• Combinations of gemcitabine with targeted agents have demonstrated no benefit over gemcitabine alone
• Gemcitabine plus erlotinib resulted in a marginal survival benefit that was statistically significant1
1Moore et al, J Clin Oncol in press
S0205: BackgroundS0205: Background
• The EGFR pathway is activated in a large proportion of human pancreatic cancers
• Pre-clinical studies have demonstrated anti-tumor activity of cetuximab in human pancreatic cancer animal models
• A pilot phase II trial suggested an improvement of one-year survival with the combination of gemcitabine and cetuximab
1Xiong et al, J Clin Oncol 22:2610, 2004
S0205:S0205: Study Schema Study Schema
Stratify
Locally advanced versus metastatic
Prior pancreatectomyYes versus No
Performance status0/1 versus 2
Gemcitabine +
Cetuximab
Gemcitabine +
Cetuximab
GemcitabineGemcitabine
RANDOMIZE
RANDOMIZE
S0205:S0205: Drug administration Drug administration
• Gemcitabine
– 1000 mg/m2 IV over 30 minutes weekly x 7 of 8, then
– 1000 mg/m2 IV over 30 minutes weekly 3 of 4
• Cetuximab
– 400 mg/m2 IV loading dose, then
– 250 mg/m2 IV weekly
S0205:S0205: Study Objectives Study Objectives
• Primary– Overall survival
• Secondary– Time to treatment failure
– Objective response
– Pain and quality of life (QoL)
– Toxicity
– EGFR expression and its correlation with outcome
S0205:S0205:EligibilityEligibility
• Histologically or cytologically confirmed pancreatic adenocarcinoma
• Incurable locally advanced or metastatic disease• Measurable or evaluable disease• No prior therapy for metastatic disease
– > 6 months from completion of adjuvant therapy
• ECOG PS 0-2• Adequate organ function• Submission of tumor tissue for EGFR assessment• Written informed consent
S0205:S0205:Statistical MethodsStatistical Methods
• Detect a 33% increase in median survival
– 92% power for the entire population– 90% power for the anticipated EGFR positive subset– One-sided 0.0125 significance level
• Designed to accrue 704 patients/ 5 years
S0205:S0205:Statistical MethodsStatistical Methods
• Actual accrual accomplished in three years (766 total; 735 eligible)
• Two interim analyses and a final analysis one year after closure of accrual
• DSMC recommended study continuation based on formal interim analyses
S0205: Patient CharacteristicsS0205: Patient Characteristics
Gem + Cetux
N =366
Gem
N = 369
Median Age (years) 63.7 64.3
Female 49% 46%
Performance Status
0/1 87% 87%
Locally Advanced 21% 22%
Measurable Disease 86.3% 88.3%
Prior Pancreatectomy 10% 11%
Overall Survival by Treatment Arm
0%
20%
40%
60%
80%
100%
0 12 24 36Months After Registration
GemcitabineGemcitabine and Cetuximab
N369366
Events338331
Medianin Months
66
P = 0.14
5.96.4
S0205 Primary Endpoint:S0205 Primary Endpoint:Survival of all PatientsSurvival of all Patients
HR = 1.09 (95% CI: 0.93, 1.27)
Progression-Free Survival by Treatment Arm
0%
20%
40%
60%
80%
100%
0 6 12 18 24 30Months After Registration
GemcitabineGemcitabine and Cetuximab
N369366
Events360351
Medianin Months
34
P = 0.058
3.03.5
S0205: S0205: Progression-Free SurvivalProgression-Free Survival
HR = 1.13 (95% CI: 0.97, 1.31)
Time to Treatment Failure by Treatment Arm
0%
20%
40%
60%
80%
100%
0 6 12 18 24Months After Registration
GemcitabineGemcitabine and Cetuximab
N369366
Events369363
Medianin Months
22
P = 0.0014
1.82.5
S0205: S0205: Time to Treatment FailureTime to Treatment Failure
HR = 1.25 (95% CI: 1.08, 1.45)
S0205: S0205: Objective Tumor ResponseObjective Tumor Response
Response Gem + Cetux (%)
N = 316
Gem (%)
N = 326
CR 0 1
PR 12 13
SD 38 30
CR + PR + SD 50 44
PD 40 47
S0205:S0205: Grade 3 or 4 Adverse Events Grade 3 or 4 Adverse Events
Toxicity
Gem + Cetux (%)
N = 353
Gem (%)
N = 353
Grade 3 Grade 4 Grade 3 Grade 4
Neutropenia 18.4 5.1 19.0 4.8
Fatigue 18.1 2.5 15.9 1.7
Nausea 8.5 0.6 5.9 0
Vomiting 6.5 0.3 2.3 0
Anemia 7.9 1.1 6.2 0
Rash 7.1 0 0 0
Anorexia 6.2 0 7.4 0
ALT 4.5 0 2.5 0
Thrombocytopenia 4.2 2.0 6.2 2.3
Allergic reaction 3.1 0.3 0 0
S0205: S0205: CONCLUSIONSCONCLUSIONS
• The addition of cetuximab to gemcitabine in patients with advanced pancreas cancer was well tolerated
• Cetuximab did not significantly improve the overall survival or time to disease progression
S0205: S0205: CONCLUSIONSCONCLUSIONS
• Ongoing analyses will determine the impact of cetuximab on pain and QoL and the contributions of EGFR expression and skin rash on outcome
• Future studies with targeted agents in pancreas cancer must focus on improving patient selection and/or the adoption of rationally designed multitargeted approaches
AcknowledgementsAcknowledgements
• Patients
• Investigators & clinical trials support personnel
• Patient advocacy & support groups
• SWOG operations, data operations, and statistical center personnel
• NCI• ImClone• Bristol Myers Squibb