OBJECTIVES

Larotrectinib is an oral tropomyosin receptor kinase (TRK) inhibitor indicated for cancers where the tumor expresses neurotrophic tyrosine receptor kinase (NTRK) gene fusions. We assessed potential budget impact of the introduction of larotrectinib. In accordance with the expected pan-tumor indication, we assessed the financial implications of covering larotrectinib across 8 tumors: colorectal, non-small cell lung, melanoma, thyroid, gastrointestinal stromal tumor, infantile fibrosarcoma, soft tissue sarcoma, and salivary gland cancer.

METHODS

: We created a budget impact model with a flexible time horizon. The model framework centralizes parameter control while separately modeling the available treatments, dosing, and market share for each of the 8 tumor types. The base case assumed a commercial U.S. health plan of 1,000,000 enrollees. The treated population for each tumor type was estimated from SEER, TRK fusion testing rate assumptions, fusion mutation prevalence, and treatment uptake assumptions. The budget impact was calculated as total and per member per month (PMPM) cost. Scenario analyses were performed in order to approximate the uncertainty in the base case results and identify likely financial determinants.

RESULTS

We estimated that less than one patient would be treated with larotrectinib across the eight tumor types in the first year after accounting for the frequency of NTRK gene fusion in each tumor type. The total costs in year 1 without larotrectinib were $41,300 compared to $68,000 with the first year of larotrectinib uptake, an increase of $26,700 (less than $0.001 PMPM). Over three years, we estimated 1 patient was treated with larotrectinib, a PMPM increase of $0.01. The increase in costs was due proportionally to increased costs of genetic testing and increased drug costs. These results were most sensitive to the parameters that define the treated population.

CONCLUSIONS

Adding larotrectinib is likely to have minimal additional costs when added to a health plan formulary.