A Pilot Study of OncoSil™ Given to Patients With Pancreatic Cancer Treated With FOLFIRINOX or Gemcitabine+Abraxane

Inclusion Criteria: 1. Histologically or cytologically proven adenocarcinoma of the pancreas. 2. Unresectable locally advanced pancreatic carcinoma. Patients with technically resectable tumours (T1-T3) will also be eligible, if they are deemed unresectable due to medical comorbidities or refusal of surgery. 3. Pancreatic target tumour diameter of ≥ 2.0 cm (shortest axis) to ≤ 6.0 cm (longest axis), as qualified by the central reading centre. 4. An ECOG Performance Status of 0 to 1 and Karnofsky Performance Status of 80 - 100. 5. Study participants ≥ 18 years of age at screening. 6. To commence first-line standard FOLFIRINOX or gemcitabine+nab-paclitaxel chemotherapy (per standard of care according to the approved prescribing schedule), within 14 days post enrolment, with OncoSil™ implantation to occur during the fourth (4th) week of the first chemotherapy cycle. 7. Provide signed Informed Consent. 8. Willing and able to complete study procedures within the study timelines. 9. Adequate renal function: serum creatinine less than 1.5 x upper limit of normal (ULN). 10. Adequate liver function: serum liver transaminases ≤ 3 × ULN and serum bilirubin ≤ 1.5 × ULN\*. \*For study participants with recent biliary obstruction treated by drainage (e.g. stent), serum bilirubin of \> 1.5 x ULN will be accepted for study entry provided that serial levels demonstrate clear improvement. In addition, chemotherapy should not be commenced until serum bilirubin is ≤ 1.5 × ULN. 11. Adequate bone marrow function: white blood cells (WBCs) ≥ 3,000/mm3, absolute neutrophil count (ANC) ≥ 1,500/mm3, haemoglobin ≥ 9 g/dL, and platelets ≥ 100,000/mm3. 12. Life expectancy of at least 3 months at the time of screening as judged by the investigator. 13. Treated with or eligible to commence prophylactic treatment with a proton-pump inhibitor prior to implantation, and to continue to receive treatment for at least 6 months post implantation. 14. Not pregnant, and if of childbearing potential, agrees to use adequate birth control (hormonal or barrier method of birth control or abstinence) prior to study entry and during the study and agrees not to donate sperm or ova, for the duration of the study and 12 months post implantation of the investigational device. Exclusion Criteria 1. Evidence of distant metastases, based on review of baseline CT scan, as determined by the central reading centre. 2. More than one primary lesion. 3. Any prior radiotherapy or chemotherapy for pancreatic cancer. 4. Use of other investigational agent at the time of screening, or within 30 days or five half-lives of Screening Visit 1, whichever is longer. 5. Pregnant or lactating. 6. In the opinion of the investigator, EUS directed implantation posing undue study participant risk. This includes: * where previous EUS-FNA was considered technically too difficult to perform; * imaging demonstrates multiple collateral vessels surrounding or adjacent to the target tumour within the pancreas; * presence (or significant risk) of varices near to the target tumour. Note: The feasibility of implantation of the target tumour and assessment of risk can be conducted at any time between Screening Visit 1 and the implantation date. A study participant should be considered for withdrawal prior to and including at the time of OncoSil™ treatment, if any of the above risk features become apparent following subject screening and/or enrolment. 7. History of malignancy, treated or untreated, within the past five years whether or not there is evidence of local recurrence or metastases, with the exception of basal cell carcinoma of the skin and cervical carcinoma in situ. 8. Evidence of radiographic invasion into stomach, duodenum or peritoneum (if not certain confirmation must be obtained prior to enrolment). 9. A known allergy or history of hypersensitivity to silicon, phosphorous or any of the OncoSil™ components. 10. Any other health condition that would preclude participation in the study in the judgment of the investigator. Note: T1-T3 is determined as per The American Joint Committee on Cancer (AJCC) tumor/node/metastasis (TNM) classification and staging system for pancreatic cancer