A Study to Assess the Safety, Tolerability, and Efficacy of NDI-219216 in Patients With Advanced Solid Tumors.

Part A Primary Objective: Incidence of dose limiting toxicities (DLTs)

Assessments will include electrocardiograms (ECGs), echocardiogram, cardiac biomarker troponin I, physical examination, vital signs (including blood pressure, pulse), and evaluation of laboratory parameters (clinical chemistry, hematology, and coagulation)

Time frame: The first 21 days of Cycle 1 (Cycle 1 is 28 days).

Part A Primary Outcome: • Incidence and severity of Adverse Events (AEs) and Serious Adverse Events (SAEs), according to NCI CTCAE v5.0

Assessments will include standard electrocardiograms (ECGs), echocardiogram, cardiac biomarker troponin I, physical examination, vital signs (including blood pressure, pulse), and evaluation of laboratory parameters (clinical chemistry, hematology, and coagulation.

Time frame: From first dose of study drug until 30 days after last dose of study drug; up to approximately 11-12 months. Each Cycle is 28 days.

Part A Primary Outcome: Incidence and severity of Treatment Emergent Adverse Events (TEAEs) and Treatment Related Adverse Events (TRAEs) as assessed by the Investigator

Assessments will include standard electrocardiograms (ECGs), echocardiogram, cardiac biomarker troponin I, physical examination, vital signs (including blood pressure, pulse), and evaluation of laboratory parameters (clinical chemistry, hematology, and coagulation).

Time frame: From first dose of study drug until 30 days after last dose of study drug; up to approximately 11-12 months. Each Cycle is 28 days.

Part B Primary Objective: Overall Response Rate (ORR) per RECIST v1.1.

Time frame: From start of study treatment until end of follow-up, up to approximately 18 months. Each Cycle is 28 days.

Part B Primary Outcome: Duration of Response (DOR) per RECIST v1.1

Time frame: From the time of first occurrence of a documented response until the time of documented disease progression or death from any cause, whichever occurs first; up to approximately 18 months. Each Cycle is 28 days.

Part B Primary Outcome: Incidence and severity of AEs according to NCI CTCAE v5.0.

Assessments will include standard electrocardiograms (ECGs), echocardiogram, cardiac biomarker troponin I, physical examination, vital signs (including blood pressure, pulse), and evaluation of laboratory parameters (clinical chemistry, hematology, and coagulation).

Time frame: From first dose of study drug until 30 days after last dose of study drug; up to approximately 18 months. Each Cycle is 28 days.

Part C Primary Objective: Overall Response Rate (ORR) per RECIST v1.1.

Time frame: From start of study treatment until end of follow-up, up to approximately 17 months. Each Cycle is 28 days.

Part C Primary Outcome: Duration of Response (DOR) per RECIST v1.1.

Time frame: From the time of first occurrence of a documented response until the time of documented disease progression or death from any cause, whichever occurs first, up to approximately 17 months. Each Cycle is 28 days.