COST-EFFICIENCY AND EXPANDED-ACCESS OF KIRSTY/MERILOG VS NOVOLOG IN DIABETES MELLITUS
Author(s)
Roselyn S. Amamoo, MD, MPH, MS1, Rosemond S. Amamoo, MD, MPH, MS1, Ivo Abraham, PhD1, Karen MacDonald, PhD2;
1R. Ken Coit College of Pharmacy, University of Arizona, Center for Health Outcomes and Pharmacoeconomic Research, Tucson, AZ, USA, 2Matrix45, LLC, Tucson, AZ, USA
1R. Ken Coit College of Pharmacy, University of Arizona, Center for Health Outcomes and Pharmacoeconomic Research, Tucson, AZ, USA, 2Matrix45, LLC, Tucson, AZ, USA
OBJECTIVES: In 2025, Kirsty and Merilog were approved by the FDA as biosimilars to Novolog (insulin aspart) in adult and pediatric diabetic patients. This study assessed the cost-efficiency and expanded-access of conversion to these biosimilars from the reference from the US payer perspective.
METHODS: A cost-efficiency and expanded-access model was applied over one year in a hypothetical panel of 100,000 diabetic patients, across daily dose increments of 10 units (10-70 U/day). Using wholesale acquisition costs (WACs), the model estimated per-patient costs and cost-savings from converting Novolog multi-dose vials and FlexPen to biosimilar formulations. It also estimated the number of patients needed to convert to generate sufficient savings to purchase one additional day, month, or year of biosimilar at the same dose and the number of additional patients who could be treated on a budget-neutral basis using conversion-generated savings.
RESULTS: Annual per-patient costs (2025 USD) for reference Novolog ranged from $264 to $1,848 for multi-dose vials and from $340 to $2,380 for FlexPen. Corresponding costs for Kirsty/Merilog, which have identical WACs, ranged from $254 to $1,778 and from $327 to $2,288. Conversion to biosimilar insulin aspart resulted in annual per-patient savings of $10-$71 for vials and up to $91 for prefilled pens, with savings increasing at higher doses. In a 100,000-patient panel, savings ranged from $101,105 at 10% conversion (10 U/day) to $7,077,350 million at 100% conversion (70 U/day) for vials, and from $130,427 to $9,129,858 million for pens, respectively. Converting approximately 26 patients for one year generated sufficient savings to fund one additional year of biosimilar treatment for another patient. At 100% conversion, savings could support treatment for nearly 4,000 additional patients annually.
CONCLUSIONS: Kirsty/Merilog multi-dose vials and prefilled pens represent cost-efficient alternatives to Novolog. Conversion can generate substantial savings that may be reinvested to expand patient access on a budget-neutral basis.
METHODS: A cost-efficiency and expanded-access model was applied over one year in a hypothetical panel of 100,000 diabetic patients, across daily dose increments of 10 units (10-70 U/day). Using wholesale acquisition costs (WACs), the model estimated per-patient costs and cost-savings from converting Novolog multi-dose vials and FlexPen to biosimilar formulations. It also estimated the number of patients needed to convert to generate sufficient savings to purchase one additional day, month, or year of biosimilar at the same dose and the number of additional patients who could be treated on a budget-neutral basis using conversion-generated savings.
RESULTS: Annual per-patient costs (2025 USD) for reference Novolog ranged from $264 to $1,848 for multi-dose vials and from $340 to $2,380 for FlexPen. Corresponding costs for Kirsty/Merilog, which have identical WACs, ranged from $254 to $1,778 and from $327 to $2,288. Conversion to biosimilar insulin aspart resulted in annual per-patient savings of $10-$71 for vials and up to $91 for prefilled pens, with savings increasing at higher doses. In a 100,000-patient panel, savings ranged from $101,105 at 10% conversion (10 U/day) to $7,077,350 million at 100% conversion (70 U/day) for vials, and from $130,427 to $9,129,858 million for pens, respectively. Converting approximately 26 patients for one year generated sufficient savings to fund one additional year of biosimilar treatment for another patient. At 100% conversion, savings could support treatment for nearly 4,000 additional patients annually.
CONCLUSIONS: Kirsty/Merilog multi-dose vials and prefilled pens represent cost-efficient alternatives to Novolog. Conversion can generate substantial savings that may be reinvested to expand patient access on a budget-neutral basis.
Conference/Value in Health Info
2026-05, ISPOR 2026, Philadelphia, PA, USA
Value in Health, Volume 29, Issue S6
Code
EE14
Topic
Economic Evaluation
Disease
SDC: Diabetes/Endocrine/Metabolic Disorders (including obesity), STA: Biologics & Biosimilars