Study of NGM120 in Subjects With Advanced Solid Tumors, Pancreatic Cancer, and Prostate Cancer Using Combination Therapy

Inclusion Criteria (Part 1 and 2): 1. Have histologically confirmed metastatic pancreatic adenocarcinoma. Recurrent unresectable pancreatic cancer is acceptable as long as the treatment is first-line. 2. Have not received any approved chemotherapy, except in the adjuvant setting. 3. Life expectancy of at least 12 weeks 4. Male subjects must agree to use contraception as per protocol during the treatment period and for at least 90 days after the last study treatment administration and refrain from donating sperm during this period. 5. Provision of an archival tumor sample (within 5 years). If an archival sample is unavailable, a fresh biopsy can be obtained during Screening. If archival tissue or biopsy sample is unavailable, the subject is ineligible. Inclusion Criteria (Part 3 Prostate Cancer): 1. Metastatic, castrate resistance, histologically confirmed prostate cancer; continuous medical castration for ≥8 weeks prior to screening. 2. Effective castration with serum testosterone levels \<0.5 ng/mL (50 ng/dL; 1.7 nmol/L). 3. Have serum GDF15 levels ≥1300 pg/mL. 4. Have experienced PSA progression under 1 or more lines of ADT in the absence or presence of radiographic and/or clinical progression, who decline or are not eligible to receive chemotherapy. 5. Have had PSA doubling time of \>3 months. Exclusion Criteria (All parts): 1. Subject was using immunosuppressive medications within 14 days before Screening with the exception of topical (intranasal, inhaled, and local injection), systemic (prednisone equivalent 10 mg/day or less), or as needed for hypersensitivity reactions such as computed tomography (CT) scan premedication. 2. Subject has active infections or other serious underlying significant medical illness, abnormal and clinically significant laboratory findings or psychiatric illness/social situation. 3. Subject is using a pacemaker, implantable cardiac defibrillator, neurostimulator, cochlear implants, cochlear implants, or other electronic medical equipment. 4. Subject has documented immunodeficiency or organ transplant. 5. Subject has an untreated central nervous system disease, leptomeningeal disease or cord compression. 6. Subject has a history, or presence, of significant cardiovascular diseases; including uncontrolled hypertension, clinically relevant cardiac arrhythmia, unstable angina or myocardial infarction within 6 months before randomization, congestive heart failure \> New York Heart Association Class II, severe peripheral vascular disease, corrected QT (QTc) prolongation \>470 msec, clinically significant pericardial effusion. 7. Subject has a history or presence of documented inflammatory bowel disease. 8. Subject is known to be positive for human immunodeficiency virus (HIV) infection.