Erlotinib and Gemcitabine With or Without Panitumumab in Treating Patients With Metastatic Pancreatic Cancer

OBJECTIVES:

Primary

- To assess whether the addition of panitumumab (a dual-epidermal growth factor receptor
inhibitor) to standard chemotherapy comprising gemcitabine hydrochloride and erlotinib
hydrochloride results in an improvement in overall survival of patients with previously
untreated, metastatic adenocarcinoma of the pancreas.

Secondary

- To compare objective response rates, progression-free survival, time to treatment
failure, quality of life, and adverse event rates in patients treated with these
regimens.

- To evaluate the downstream marker, KRAS, in stool specimens.

OUTLINE: This is a multicenter study. Patients are stratified according to ECOG performance
status (0 vs 1) and prior adjuvant chemotherapy (yes vs no). The first 6 patients are
assigned to arm II. Subsequent patients are randomized to 1 of 2 treatment arms.

- Arm I: Patients receive gemcitabine hydrochloride IV over 30 minutes on days 1, 8, and
15 and oral erlotinib hydrochloride once daily on days 1-28. Treatment repeats every 28
days for 2 courses. Patients achieving a complete response (CR) after 2 courses receive
2 additional courses of treatment; patients achieving a partial response (PR) receive
retreatment as above in the absence of disease progression or unacceptable toxicity.
Patients achieving a CR after 4 courses of treatment receive maintenance therapy
comprising erlotinib hydrochloride daily until the first disease progression. After the
first progression, patients are retreated with gemcitabine hydrochloride and erlotinib
hydrochloride until second progression (using the first progression tumor measurements
as the new baseline reference).

- Arm II: Patients receive gemcitabine hydrochloride and erlotinib hydrochloride as in
arm I and panitumumab IV over 1 hour on days 1 and 15. Treatment repeats every 28 days
for 2 courses. Patients achieving a CR after 2 courses receive 2 additional courses of
treatment; patients achieving a PR receive retreatment as above in the absence of
disease progression or unacceptable toxicity. Patients achieving a CR after 4 courses
of treatment receive maintenance therapy comprising erlotinib hydrochloride daily and
panitumumab every 2 weeks until the first disease progression. After the first
progression, patients are retreated with gemcitabine hydrochloride, erlotinib
hydrochloride, and panitumumab until second progression (using the first progression
tumor measurements as the new baseline reference).

Stool samples are collected at baseline and analyzed for KRAS mutations via protein
analyses.

Quality of life will be assessed at baseline, every 2 courses during treatment, and at the
end of treatment.

After the second progression, patients are followed every 3-6 months for 2 years.

DISEASE CHARACTERISTICS:

- Histologically or cytologically confirmed adenocarcinoma of the pancreas (ductal or
undifferentiated)

- Metastatic disease

- No islet cell, acinar cell, or cystadenocarcinomas

- No locally advanced disease

- No history or known presence of CNS metastases

PATIENT CHARACTERISTICS:

- ECOG performance status 0-1

- Life expectancy ≥ 3 months

- ANC ≥ 1,500/mm^3

- Platelet count ≥ 100,000/mm^3

- Total bilirubin ≤ 2 times upper limit of normal (ULN) (patients may be stented)

- AST ≤ 2.5 times ULN

- Creatinine ≤ 2.0 times ULN

- Magnesium ≥ lower limit of normal

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- Willing to provide a stool specimen

- No malignancy diagnosed within the past 3 years except basal cell or squamous cell
skin cancer, prostate cancer (Gleason < 7), or carcinoma in situ of the cervix

- No uncontrolled intercurrent illness including, but not limited to, ongoing or active
infection, or psychiatric illness/social situations that would limit compliance with
study requirements

- No clinically significant cardiovascular disease (i.e., myocardial infarction,
unstable angina, symptomatic congestive heart failure, or serious uncontrolled
cardiac arrhythmia) within the past year

- No known positive test(s) for HIV infection, hepatitis C virus, or acute or chronic
active hepatitis B infection

- No liver dysfunction from cirrhosis or viral hepatitis

- No enteral hyperalimentation

- No grapefruit or grapefruit juice during the study

PRIOR CONCURRENT THERAPY:

- Recovered from prior therapy

- More than 4 months since prior radiotherapy, immunotherapy, or biologic therapy

- More than 4 weeks since prior and no elective or planned major surgery

- More than 2 weeks since prior minor and no elective or planned surgery

- No prior cytotoxic chemotherapy for metastatic disease

- Adjuvant chemotherapy for completely resected disease or chemoradiotherapy for
locally advanced disease is allowed, provided it was administered > 6 months
prior to study entry

- Adjuvant chemotherapy must not have contained an EGFR inhibitor

- Gemcitabine hydrochloride used as either a radiosensitizer or as maintenance
therapy is allowed, provided more than 6 months have elapsed since the last day
of treatment

- No prior anti-EGFR antibody therapy (e.g., cetuximab) or treatment with small
molecule EGFR inhibitors (e.g., gefitinib hydrochloride, erlotinib hydrochloride, or
lapatinib)

- No concurrent immunotherapy or radiotherapy

- No other concurrent chemotherapy

- No concurrent colony-stimulating factors during the first course of study therapy