Figure 1.
![Patient and patient-derived xenograft data on Larotrectinib in a pediatric B-cell ALL patient. (A) Treatment course and cerebrospinal fluid (CSF) cell count over time. The day of first relapse post-HSCT (day 50 post-HSCT) was set as day 0. (B) Larotrectinib plasma and CSF concentrations. (C) Preclinical efficacy of larotrectinib initiated at 2 time points (day +1 postinjection [“laro early”] and day +8 postinjection [“laro late”]) in an NSG xenograft model (n = 5 mice per group). Images of spleens, spleen volumes, infiltration of bone marrow (BM) and spleens (SP) by flow cytometry, and CNS infiltration by morphology. **P < .0001.](https://ash.silverchair-cdn.com/ash/content_public/journal/bloodadvances/3/22/10.1182_bloodadvances.2019000700/1/advancesadv2019000700f1.png?Expires=1736044386&Signature=BebfLnv9ynMSvxdCISlrY0T8Z-akez9KAAmvyyhobqDupxGcyDwh8lLfNZC6bdiE7OiRvmCnSE6KAIpaxWEfV6xcxpcBlwYo7pbSiW4tdqzc15dHiXrXn8aju8ShFtX0MzcQzsmpLxdBf3YN4Fvs7NHmwLXaaaq-RfAih4W35PHyMDCHp1rvfivilIFm5nC~a7d68FPPSxWbe1kh8cVa6RjVLqHB0hxZFOzVt2J15QBYQPW2fs0PetF7t2Wfzy8yGQDkDrfyxO2AK53vCuVDGL-IAVaLStkV~p1AyngPcSaABg2B2WkRSdgAM9O07BO9E3WqBade-eyxbyopnvBEOQ__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Patient and patient-derived xenograft data on Larotrectinib in a pediatric B-cell ALL patient. (A) Treatment course and cerebrospinal fluid (CSF) cell count over time. The day of first relapse post-HSCT (day 50 post-HSCT) was set as day 0. (B) Larotrectinib plasma and CSF concentrations. (C) Preclinical efficacy of larotrectinib initiated at 2 time points (day +1 postinjection [“laro early”] and day +8 postinjection [“laro late”]) in an NSG xenograft model (n = 5 mice per group). Images of spleens, spleen volumes, infiltration of bone marrow (BM) and spleens (SP) by flow cytometry, and CNS infiltration by morphology. **P < .0001.