Rapid Readouts: Larotrectinib Prior Therapy and Performance Status Outcomes in Patients With Non-CNS TRK Fusion Cancer

OncLive® Rapid Readout from European Society for Medical Oncology 2021: Results for Larotrectinib in Non-CNS TRK Fusion Cancer Patients: Outcomes by Prior Therapy and Performance Status

Segment Description:

Alexander Drilon, MD, discusses data from the following presentation: “Larotrectinib in Non-CNS TRK Fusion Cancer Patients: Outcomes by Prior Therapy and Performance Status.” (ESMO Drilon Abstract 534P)

Segment Body Content:

• Larotrectinib is a first-in-class, highly selective, central nervous system (CNS)-active tropomyosin receptor kinase (TRK) inhibitor approved in over 40 countries, and by the European Medicines Agency, for the treatment of adult and paediatric patients with TRK fusion cancer. Here, we report updated data on larotrectinib outcomes stratified by prior lines of systemic therapy and baseline performance status.
• Methods
  • Data were pooled from 3 clinical trials of patients with non-CNS TRK fusion cancer treated with larotrectinib (NCT02122913, NCT02576431, and NCT02637687).
  • Patients were stratified based on the number of lines of prior systemic therapy (0, 1, 2 or ≥ 3) or baseline Eastern Cooperative Oncology Group performance status (ECOG PS) (0, 1, 2 or 3), or the equivalent Lansky/Karnofsky performance status for children.
  • A post-hoc analysis of objective response rate (ORR; as assessed by investigators using Response Evaluation Criteria in Solid Tumors v1.1), duration of response (DoR), progression-free survival (PFS) and overall survival (OS) was performed.
• Results
  • 218 patients were enrolled.
  • ORR: 75% (95% confidence interval [CI] 68–81).
  • Median DoR (mDoR): 49.3 months (95% CI 27.3–not estimable [NE]).
  • Median PFS (mPFS) was 35.4 months (95% CI 23.4–55.7).
  • 36-month OS rate: 77% (95% CI 69–84).
  • The incidence of treatment-related Grade 3–4 adverse events for patients with 0, 1, 2 or ≥ 3 prior lines of systemic therapy was 19%, 24%, 14% and 14%, respectively.
• Conclusions
  • Although the response rates were highest in patients who were treatment-naïve or with an ECOG PS of 0, larotrectinib benefitted patients across varying degrees of pre-treatment and baseline ECOG PS.