Study of the Pharmacokinetics, Pharmacodynamics, Safety and Tolerability of Fosaprepitant for the Prevention of Chemotherapy-Induced Nausea and Vomiting (CINV) in Children (MK-0517-029)

As a result of Protocol Amendment 04, only one dose equivalent of open-label fosaprepitant
(5 mg/kg for participants <12 years to <=4 months of age, 2.5 mg/kg for participants <4
months to 1 month of age and 1.25 mg/kg for participants <1 month to 0 months of age) will
be evaluated in children aged birth to <12 years to allow for further pharmacokinetic,
pharmacodynamic, safety and tolerability assessments of fosaprepitant in participants from
birth to <12 years of age.

Inclusion Criteria:

- Is 0 months (at least 37 weeks gestation) to <18 years of age (Amendment 04: Changed
age eligibility criterion to: birth to <12 years of age)

- Scheduled to receive chemotherapeutic agent(s) associated with moderate, high, or
very high risk of emetogenicity for no more than 5 consecutive days for a documented
malignancy, or a chemotherapy regimen not previously tolerated due to vomiting

- Expected to receive ondansetron as part of antiemetic regimen (Cycle 1); Expected to
receive a 5-HT3 antagonist as part of antiemetic regimen (Cycles 2-6)

- If female and has begun menstruating, must have a negative pregnancy test prior to
study participation and agree to remain abstinent or use a barrier form of
contraception

- Predicted life expectancy of >=3 months

- Pre-existing functioning central venous catheter

- Weight >=3rd percentile for age and gender (and >=3.0 kg)

Exclusion Criteria:

- Vomited in the 24 hours prior study drug administration (Cycle 1)

- Current user of any illicit drugs (including marijuana) or current evidence of
alcohol abuse

- Scheduled to receive stem cell rescue therapy in conjunction with study related
course(s) of emetogenic chemotherapy

- Received or will receive radiation therapy to the abdomen or pelvis in the week prior
to study drug administration and/or during the course of the study

- Pregnant or breast feeding

- Allergic to fosaprepitant, aprepitant, ondansetron, or any other 5-HT3 antagonist

- Has a symptomatic central nervous system (CNS) tumor causing nausea and/or vomiting

- Has an active infection, congestive heart failure, slow heart rate, or other
uncontrolled disease other than cancer

- Mentally incapacitated or has a significant emotional or psychiatric disorder

- Known history of QT prolongation or is taking any medication known to lead to QT
prolongation

- Taking other excluded medications

- Participated in any previous study of aprepitant or fosaprepitant, or taken an
investigational drug within 4 weeks prior to study participation