Pharmacoeconomic Impact of Thiotepa-Containing Conditioning Regimens in a Pediatric Hematopoetic Stem Cell Transplant Center

Thiotepa-containing conditioning regimens remain standard of care for certain malignancies in several pediatric hematopoetic stem cell transplant centers.  Most commonly, thiotepa containing regimens are utilized in autologous preparative regimens for central nervous system tumors; however, it has also been utilized in regimens for neuroblastoma.  These two diagnoses are among the most common diagnoses for autologous stem cell transplantation in our institution.  Currently there is only one manufacturer of thiotepa, which has resulted in marked price increases over the past several years.  Typical drug cost for thiotepa can exceed $100,000 for the conditioning regimen of one adolescent.  Thiotepa costs have exceeded $285,000 for 5 patients over the course of the past 24 months at our single institution.    

The rise in thiotepa costs has resulted in a need to further evaluate alternative conditioning regimens.  Pediatric data exists to support the use of conditioning regimens such as busulfan/melphalan and carboplatin/etoposide/melphalan in other pediatric oncologic disease states.  There remains a need for more robust clinical trial data comparing the efficacy and safety between these alternative conditioning regimens to further determine if there is true benefit of a thiotepa-containing conditioning regimen.

As data remains lacking on the superiority of a certain preparative regimen for such pediatric oncologic disease states such as central nervous system tumors, it is imperative to assess the potential pharmacoeconomic impact of utilizing non-thiotepa containing regimens.  When comparing conditioning regimens, drug cost would be $109,378 for a thiotepa/cyclophosphamide regimen in a patient with a body surface area of 2 m².  Comparatively, a conditioning regimen of cyclophosphamide/etoposide/melphalan would cost $9,825 in a patient with a BSA of 2 m².  A thiotepa/cyclophosphamide regimen roughly costs ten times the cost of cyclophosphamide/etoposide/melphalan and three times the cost of a busulfan/melphalan containing regimen. The opportunity to be more economically responsible in a small group of patients will have a large impact on drug expenditures.   As the price of thiotepa continues to rise and alternative regimens are utilized more frequently, there remains a responsibility for the practitioner to report and determine the most effective, safe, and economically responsible pediatric hematopoietic stem cell transplant conditioning regimen.