The purpose of this study is to determine disease response of GEMOX-Panitumumab (GEMOX-P) in KRAS/ BRAF wild-type, Stage IV, biliary tract and gallbladder cancer patients who have previously not received chemotherapy. This study will also examine the potential toxicities, progression-free and overall survival in this population.

Inclusion Criteria:

• Histologically confirmed metastatic or unresectable Kras and Braf wild-type biliary tract adenocarcinoma (bile ducts, hepatic duct, cystic duct, common bile duct, ampulla of Vater or gallbladder adenocarcinoma).
• Screening for tumor Kras and Braf mutations requires formalin fixed paraffin embedded tumor blocks from core needle excisional biopsy.
• Participants must have measurable disease.
• No prior chemotherapy for biliary tract or gallbladder cancer. Prior chemoembolization or radiation to the liver allowed as long as measurable disease outside chemoembolization or radiation area and other baseline characteristics met and at least 4 weeks has lapsed since therapy. No prior gemcitabine or oxaliplatin or anti-EGFR therapies including panitumumab therapy allowed.
• Age minimum 18 years old.
• Life expectancy of greater than 3 months.
• ECOG performance status < 1
• Participants must have normal organ and marrow function as defined below:
• Leukocytes > 3,000/mcL Absolute neutrophil count > 1,500/mcL Platelets > 100,000/mcL hemoglobin > 9mg/dL Mg > 1.2 mEq/L total bilirubin < 2.5 mg/dL AST (SGOT)/ALT (SGPT) < 2.5 X institutional upper limit of normal (unless liver is involved with tumor, in which case the transaminases must be 5 x upper limits of normal), creatinine within normal institutional limits or creatinine clearance > 60 mL/min/1.73 m2 for subjects with creatinine levels about institutional normal
• Patients with concurrent malignancy may be included if disease is characterized by one of the following definitions: 1. Malignancy treated with curative intent and with no known active disease present for 3 years prior to randomization and felt to be at low risk for recurrence by the treating physician. 2. Adequately treated non-melanomatous skin cancer or lentigo maligna without evidence of disease. 3. Adequately treated cervical carcinoma in situ without evidence of disease. 4. Prostatic intraepithelial neoplasia without evidence of prostate cancer. 5. DCIS without evidence of breast cancer.
• Ability to understand and the willingness to sign a written informed consent document.
• Patients may have prior placement of stents or shunts to relieve biliary obstruction.

Exclusion Criteria:

• Participants who have had chemotherapy or radiotherapy within 4 weeks prior to entering the study or those who have not recovered from adverse events due to agents administered more than 4 weeks earlier.
• Participants may not be receiving any other study agents.
• Participants with known brain metastases.
• History of allergic reactions attributed to compounds of similar chemical or biologic composition to gemcitabine, oxaliplatin or panitumumab.
• Patients with preexisting peripheral neuropathy of grade 2 or greater severity according to the Common Terminology Criteria of the NCI (version 3.0) are ineligible.
• Patients with biliary obstruction with inadequate drainage and total bilirubin > 2.5 mg/dL are ineligible.
• Uncontrolled intercurrent illness including, but not limited to ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements,
• History of interstitial lung disease e.g. pneumonitis or pulmonary fibrosis or evidence of interstitial lung disease on baseline chest CT scan.
• Known positive test(s) for HIV, hepatitis C virus, acute or chronic active hepatitis B infection.
• Pregnant women are excluded.

Adverse events were collected for the duration of treatment.