The primary purpose of this study is to compare pembrolizumab/vibostolimab to pembrolizumab
with respect to recurrence-free survival (RFS). The primary hypothesis is that
pembrolizumab/vibostolimab is superior to pembrolizumab with respect to RFS as assessed by
the investigator in participants with high-risk resected Stage IIB, IIC, III and IV melanoma.

Severe Aplastic Anemia (SAA) is a rare condition in which the body stops producing enough new
blood cells. SAA can be cured with immune suppressive therapy or a bone marrow transplant.
Regular treatment for patients with aplastic anemia who have a matched sibling (brother or
sister), or family donor is a bone marrow transplant. Patients without a matched family donor
normally are treated with immune suppressive therapy (IST). Match unrelated donor (URD) bone
marrow transplant (BMT) is used as a secondary treatment in patients who did not get better
with IST, had their disease come back, or a new worse disease replaced it (like leukemia).

This trial will compare time from randomization to failure of treatment or death from any
cause of IST versus URD BMT when used as initial therapy to treat SAA.

The trial will also assess whether health-related quality of life and early markers of
fertility differ between those randomized to URD BMT or IST, as well as assess the presence
of marrow failure-related genes and presence of gene mutations associated with MDS or
leukemia and the change in gene signatures after treatment in both study arms.

This study treatment does not include any investigational drugs. The medicines and procedures
in this study are standard for treatment of SAA.

Difluoromethylornithine (DFMO) will be used in an open label, single agent, multicenter,
study for patients with neuroblastoma in remission. In this study subjects will receive 730
Days of oral difluoromethylornithine (DFMO) at a dose of 750 mg/m2 250 mg/m2 BID (strata 1,
2, 3, and 4) OR 2500 mg/m2 BID (stratum 1B) on each day of study. This study will focus on
the use of DFMO in high risk neuroblastoma patients that are in remission as a strategy to
prevent recurrence.