• PRE-SCREENING: Written informed consent prior to any Pre-Screening activities, study-specific procedures or interventions

• PRE-SCREENING: At least 18 years of age at time of informed consent. Persons of all gender identities, biological sexes, races, and ethnicities will be included

• PRE-SCREENING: A diagnosis of advanced sarcoma or advanced prostate, breast, ovarian, or pancreatic cancer. Change in an individual's cancer can be tracked objectively according to the Prostate Cancer Working Group 3 (PCWG3) criteria for prostate cancer, and Response Evaluation Criteria in Solid Tumors (RECIST) version (v) 1.1 criteria for sarcomas and breast, ovarian, and pancreatic cancers

• PRE-SCREENING: Biospecimen collection, as per institutional standards, must be consented to and collection must be feasible, with the following exceptions for tissue collections:

‣ Individuals with a prior tumor tissue sample with successful SMMART-Clinical Analytics Platform (CAP) assays, collected within the last 90 days, may be eligible, so long as ≤ 1 treatment has been received within ≤ 90 days of that biopsy

• PRE-SCREENING: Eastern Cooperative Oncology Group (ECOG) performance status of ≤ 2

• PRE-SCREENING: Physician-assessed life expectancy of ≥ 6 months

• PRE-SCREENING: Additional eligibility criteria specific to their disease must also be met

• PRIMARY TREATMENT: Documented progression after at least 1 line of prior therapy for advanced disease. If recurrence occurred within 6 months of the last dose of an adjuvant/neoadjuvant therapy, that adjuvant/neoadjuvant therapy will count as 1 line of therapy

• PRIMARY TREATMENT: SMMART-ACT tumor board recommendation of at least one SMMART-ACT therapy regimen defined within this protocol, based on the board's review of SMMART-CAP results on a pre-screening biopsy

• PRIMARY TREATMENT: Absolute neutrophil count (ANC) ≥ 1,500/uL (1.5 K/cu mm) (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Platelets ≥ 100,000/uL (100 K/cu mm) (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Hemoglobin ≥ 9 g/dL (or ≥ 5.6 mmol/L) (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Creatinine OR measured or calculated creatinine clearance (glomerular filtration rate \[GFR\] can also be used in place of creatinine or creatinine clearance \[CrCl\]) ≤ 1.5 x institutional upper limit of normal (ULN) (institutional upper limit of normal \[IULN\]) OR ≥ 50 mL/min/1.73 m\^2 (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

‣ Creatinine clearance should be calculated per institutional standard. For participants with a baseline calculated creatinine clearance below normal institutional laboratory values, a measured baseline creatinine clearance should be determined. Individuals with higher values felt to be consistent with inborn errors of metabolism will be considered on a case-by-case basis.

⁃ Creatinine clearance of \> 30 mL/min may be considered given that renal toxicity is not at increased risk and excretion is not major route of clearance for any chosen SMMART-ACT therapeutic

• PRIMARY TREATMENT: Total bilirubin ≤ 1.5 x IULN OR direct bilirubin ≤ IULN for individuals with total bilirubin levels \> 1.5 x IULN (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Aspartate aminotransferase (AST)(serum glutamic oxaloacetic transaminase \[SGOT\])/ Alanine aminotransferase (ALT) (serum glutamic pyruvic transaminase \[SGPT\]) ≤ 3 x IULN (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: International normalized ratio (INR) or prothrombin time (PT) ≤ 1.5 x ULN, unless individual is receiving anticoagulant therapy, as long as PT or partial thromboplastin time (PTT) is within intended therapeutic range of intended anticoagulant therapy (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Activated partial thromboplastin time (aPTT) or PTT ≤ 1.5 x ULN, unless participant is receiving anticoagulant therapy, as long as PT or PTT is within therapeutic range of intended anticoagulant therapy (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

• PRIMARY TREATMENT: Body mass index (BMI) \> 16.0 and \< 35.0 kg/m\^2 (assessed at primary \[post pre-screening\] screening, or by the time that study intervention commences)

‣ Participants with a BMI of ≥ 30.0 will use ideal body weight indices in calculating the delivery of agents that are dosed based upon body surface area (i.e., mg agent/meter squared) or weight (i.e., mg agent/kg body weight)

• PRIMARY TREATMENT: Toxicities due to prior therapies should be resolved to baseline or grade 1 (per Common Terminology Criteria for Adverse Events \[CTCAE\] version \[v\] 5.0) before administration of study intervention. The following exceptions are permitted:

‣ Alopecia, fatigue, and lymphopenia due to prior therapies.

⁃ Toxicities attributed to prior anti-cancer therapy that are not expected to resolve and to result in long lasting sequelae (e.g., neuropathy after platinum-based therapy), may be permitted

• PRIMARY TREATMENT: Palliative radiation therapy completed ≥ two weeks prior to start of SMMART-ACT treatment to a measurable disease lesion(s)

• PRIMARY TREATMENT: Study intervention-specific eligibility criteria for the intended, recommended therapy must also be met

• CANCER-SPECIFIC CRITERIA (BREAST CANCER): Lesion(s) remain measurable after systemic therapies, as follows:

‣ At least one prior line of pharmacological therapy for hormone receptor (HR) positive, human epidermal growth factor receptor 2 (HER2)-negative disease.

⁃ At least one prior line of targeted therapy for HER2-positive disease

⁃ At least one prior line of combination therapy for triple negative disease lacking a BRCA1/2 mutation.

⁃ At least one prior line of therapy with a PARP inhibitor for triple negative disease with a BRCA1/2 mutation