Inclusion Criteria:

1. Ability to swallow capsules

2. Body surface area (BSA): Subjects must have a body surface area 0.45 m2 at the time
of the study enrollment

3. Disease status: Subjects must have measurable or evaluable disease, by RECIST v1.1
Curie Scale Criteria

4. Tumor type:

Part A: Relapsed or refractory extracranial solid tumors Part B: Relapsed or
refractory primary CNS tumors Part C: Relapsed or refractory neuroblastoma Part D:
Relapsed or refractory non-neuroblastoma, extracranial solid tumors with NTRK1/2/3,
ROS1, or ALK gene rearrangements documented by a CLIA-approved lab prior to
enrollment

5. Histologic/molecular diagnosis of malignancy at diagnosis or the time of relapse

6. Archival tumor tissue from diagnosis or, preferably, at relapse

7. Age: Male or female age 2 years and < 22 years

8. Performance status: Lansky or Karnofsky score 60%

9. Patient's cancer must have relapsed after or failed to respond to frontline curative
therapy or there must not be other potentially curative treatment options available

10. Adequate organ and neurologic function

11. Females of child bearing potential must have a negative serum pregnancy test within
14 days prior to entrectinib dosing

Exclusion Criteria:

1. Receiving other experimental therapy

2. Known congenital long QT syndrome

3. Known active infections

4. Receiving Enzyme Inducing Antiepileptic Drugs (EIAEDs) within 14 days of first dose.

5. Incomplete recovery from acute effects of any surgery prior to treatment.

6. Active gastrointestinal disease or other malabsorption syndromes that would impact
drug absorption.

7. Other severe acute or chronic medical or psychiatric condition or lab abnormality
that may increase the risk associated with study participation, drug administration
or may interfere with the interpretation of study results.

Minimum Eligible Age: 2 Years

Maximum Eligible Age: 22 Years

Eligible Gender: Both