A Study of TSC-100 and TSC-101 in AML, ALL and MDS in Patients Undergoing Allogeneic Peripheral Blood Stem Transplantation

Inclusion Criteria: * Male or female aged ≥ 18 years at the time of signing the informed consent. * Eastern Cooperative Oncology Group (ECOG)-PS ≤ 2 at the time of the screening visit. * Contraceptive use by male and female participants must be consistent with local regulations regarding the methods of contraception for those participating in clinical studies. * Male Participants: * A male participant must agree to use a highly effective contraceptive as detailed in Appendix 4 of this protocol during the intervention period and for at least 12 months after the last dose of study intervention and refrain from donating sperm during this period. * Female Participants: * A female participant is eligible to participate if she is not pregnant, not breastfeeding, and at least one of the following conditions applies: * Not a woman of childbearing potential (WOCBP) OR * A WOCBP who agrees to follow the contraceptive guidance during the intervention period and for at least 12 months after the last dose of study intervention. * Preparing to undergo allogeneic HCT for either of the following: * AML * MDS * ALL * Participants in the treatment arms must express HLA-A\*0201. Participants in the control arm may express any HLA type. * Having the HA1+/- or HA-1+/+ (HA-1 positive) genotype to be eligible for TSC-100 treatment. * Having the HA2+/- HA-2+/+ (HA-2 positive) genotype to be eligible for TSC-101 treatment. * Having a haploidentical donor, MMUD, or MUD for HCT who is adequately HLA-m…