A Study of MX006 in Patients With Advanced and/or Metastatic Tumors Known to Express B7-H3

Inclusion Criteria: * Male and female patients aged 18 years-or older at the time of signature of the informed consent form. * Patients with advanced/metastatic cancer, with measurable disease as determined by RECIST v1.1 or the Prostate Cancer Clinical Trials Working Group 3 (for mCRPC only) as per Investigator discretion. Note: Patients with mCRPC can be enrolled without measurable disease but must have a minimum of 2 bone lesions and increased PSA. * Histologically or cytologically confirmed unresectable locally advanced or metastatic solid tumors in patients with relapsed or refractory solid tumors known to express B7-H3 who have failed available standard therapy or who are not candidates for standard therapy. * Has adequate bone marrow and organ function within 7 days before the start of study * Has an adequate treatment washout period prior to start of study treatment, defined as: * Major surgery: ≥4 weeks (or 2 weeks for low-invasive cases \[e.g., colostomy\]). Note: major surgery is defined for example as a surgical procedure that is complex, invasive (e.g., enters a body cavity), is associated with higher risk of complications, and may require general anesthesia and hospitalization. * Radiation therapy: ≥4 weeks (if palliative single site stereotactic radiation therapy, ≥2 weeks.) Exclusion Criteria: * Prior treatment with an NMT inhibitor or any antibody-drug conjugate (ADC) that delivers an NMTi payload. * Has other invasive malignancy within 2 years; prior or concurrent non-invasive malignancies (with the exception of the following: in situ carcinomas of the cervix, non-melanoma skin cancers) and/or patients with localized malignancies that were treated with curative intent (e.g., localized breast cancer) who remain disease-free and are considered low likelihood for recurrence who may be enrolled on a case-by-case basis after discussion with the Medical Monitor). * Have clinically significant cardiac disease, known congestive heart failure (New York Heart Association classes II-IV) or a serious cardiac arrhythmia requiring treatment, and/ or a known decreased cardiac ejection fraction of \< 45%. A baseline QT interval as corrected by Fridericia's formula (QTcF) \> 470 msec, a complete left bundle branch block (defined as a QRS interval ≥ 120 msec in left bundle branch block form) or an incomplete left bundle branch block based on the average of triplicate 12-lead electrocardiogram (ECG) per local read. * Received any of the following within the specified time frame prior to administration of study treatment: Any systemic agent from a previous treatment regimen or clinical study including anti-cancer chemotherapy or small molecule ≤14 days or 5 half-lives (whichever is shorter); any biologic or hormonal agent ≤28 days or 5 half-lives (whichever is shorter). * Received any of the following within the specified time frame prior to administration of study treatment: Platelet transfusion, red blood cell transfusion and/or granulocyte colony-stimulating factor administration \< 1 week prior to screening assessments. Other protocol defined Inclusion/Exclusion criteria may apply.