Background: Biosimilars have contributed to the reduction in the cost of prophylaxis of CIN/FN in recent years. Savings generated from conversion to biosimilars could be reallocated on a budget-neutral basis to provide expanded access to additional prophylaxis or to anti-neoplastic treatment. To demonstrate this, we simulated: 1) the savings that could be realized from CIN/FN prophylaxis with biosimilar pegfilgrastim-cbqv (BIOSIM-PEG) over reference pegfilgrastim with or without on-body injector (PEG/PEG-OBI), 2) a model of expanded access to BIOSIM-PEG from cost-savings achieved from conversion from PEG/PEG-OBI, 3) a model of expanded access to chemotherapy with oxaliplatin, leucovorin, irinotecan, and fluorouracil (FOLFIRINOX) for metastatic pancreatic cancer (mPC), 4) the number-needed-to-convert (NNC) to BIOSIM-PEG to purchase one additional treatment of BIOSIM-PEG, and 5) the NNC to purchase one cycle of FOLFIRINOX. Methods: This simulation modeling from the US payer perspective utilized: 1) a blended rate of average selling price (ASP; derived from CMS Q4 2020 reimbursement) and wholesale acquisition cost (WAC; Redbook) for PEG/PEG-OBI, BIOSIM-PEG, and all FOLFIRINOX agents proportionate to the estimated 2020 incident pancreatic cancer age distribution per Surveillance, Epidemiology, and End Results Program (67.6% Medicare-insured patients ≥65 years of age; 32.4% commercially insured patients <65 years); 2) between one and twelve cycles of prophylaxis in a panel of 2,500 mPC patients treated with FOLFIRINOX; and 3) conversion rates from PEG/PEG-OBI to BIOSIM-PEG ranging from 10%—100%. Results: Using a current blended ASP/WAC rate, cost-savings of BIOSIM-PEG over PEG/PEG-OBI in a panel of 2,500 mPC patients range from $188,780 (for 1 cycle of prophylaxis at 10% conversion) to $22,653,609 (12 cycles at 100%). In a single cycle of chemotherapy, these savings translate into expanded access to additional BIOSIM-PEG prophylaxis ranging from 53 cycles at 10% conversion from PEG/PEG-OBI to 528 cycles at 100% or to between 321 to 3,214 cycles of FOLFIRINOX, respectively. The savings over twelve cycles could provide up to 6,330 additional cycles of BIOSIM-PEG or 38,571 cycles of FOLFIRINOX (at 100% conversion). The NNC from PEG/PEG-OBI to purchase one additional cycle of BIOSIM-PEG is 4.74; the NNC to purchase once cycle of FOLFIRINOX is 0.78. Conclusions: These simulated models demonstrate the magnitude of the cost savings for CIN/FN prophylaxis that can be generated by conversion to biosimilar pegfilgrastim-cbqv. Further, these savings could be reallocated to provide access to anti-neoplastic treatment on a budget-neutral basis, thus enhancing the value of cancer care to both payers and patients.