Pharmakoökonomie: Open Access

The Economic Impact of Changing Levothyroxine Formulations in Difficult-to-Treat Hypothyroid Patients: An Evidence-Based Model

Abstract

Riad Elmor, Walter Sandulli and Charles A. Carter

Objective: To determine the budget impact of incorporating levothyroxine gel caps in the treatment plan of patients diagnosed with hypothyroidism who experience multiple levothyroxine dose or formulation changes annually due to inadequate efficacy or tolerability.

Methods: Cost estimates of levothyroxine formulations were obtained. Estimated utilization patterns and costs of physician services, laboratory tests, ancillary healthcare services, and lost productivity were quantified based on published literature and government/public sources. The patient population was based on epidemiology reports and estimates from the American Association of Clinical Endocrinology and the American Thyroid Association. All calculations of economic outcomes were determined using a budget impact model constructed in a MS Excel platform.

Results: The economic model demonstrated for a population of 500,000 persons, there are 23,000 (4.6%) people with hypothyroidism, of which 18,400 (80.0%) receive pharmacologic treatment, including 17,480 (95.0%) that receive levothyroxine. The proportion of patients requiring ≥ 1 dosage changes annually is 31.4%, producing 5,489 “hard-to-treat” patients. Similarly, the proportion of patients requiring ≥ 2 dosage changes annually is 8.0% or 1,398 “harder-to-treat” patients. Using evidence-based data of the tolerability and absorption characteristics of levothyroxine gel caps, changing 20.0% of the target cohort to the gel cap formulation produced annual net cost savings of $542,901 in direct medical costs and $564,650 in lost productivity for “hard-to-treat” patients and savings of $409,107 in direct medical costs and $441,926 in lost productivity for “harder-to-treat” patients.

Conclusions: Consideration of switching levothyroxine product from a tablet to a gel cap formulation is justified on an economic and therapeutic basis for hypothyroid patients at risk of sub adequate drug efficacy or tolerability as measured by the need for one or more annual levothyroxine dosage or formulation adjustments.