Inclusion Criteria:
* Must provide written informed consent before any study-specific procedures or interventions are performed
* Must be ≥ 18 years old at the time of informed consent
* Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
* Clinically-confirmed diagnosis of locally-advanced or metastatic adenocarcinoma of the pancreas
* Participants may be treatment naïve or have received prior therapy for the treatment of their PDAC. A minimum washout period of 14-days after completing the most recent line of therapy is required before a participant can initiate treatment with study agent(s)
* Based on available imaging, participant must have at least one disease lesion that can be biopsied in accordance with institutional standards
* Patient agrees to undergo a minimum of 2 biopsies (pre- and post-treatment). Note: at principal investigator (PI) discretion, archival sample may be obtained in lieu of pre-treatment biopsy
* Hemoglobin ≥ 7.5 g/dL
* Absolute neutrophil count (ANC) ≥ 1.0 x 10\^9/L (\> 1500 per mm\^3)
* Platelet count ≥ 75 x 10\^9/L (\> 100,000 per mm\^3)
* Calculated creatinine clearance \> 50 mL/min/1.73m\^2 (per Cockcroft-Gault equation)
* Aspartate aminotransferase (AST)/alanine aminotransferase (ALT): ≤ 3 x upper limit of normal (ULN), or ≤ 5 x ULN in presence of liver metastases
* Participants of childbearing potential (POCBP) must agree to abstain from sexual intercourse or use effective methods of contraception starting with the first dose of study therapy through 6 months from the last dose of study intervention
* POCBP may participate provided they have a negative serum pregnancy test at screening and a negative serum OR urine pregnancy test within 7 days of starting treatment
* Sperm-producing participants must agree to abstain from sexual intercourse or use effective contraception starting with the first dose through 6 months after last dose of study intervention
Exclusion Criteria:
* Concomitant use of other anti-cancer therapy otherwise not permitted in this protocol, including: chemotherapy, immunotherapy, hormonal therapy (hormone replacement therapy is acceptable), radiotherapy (except for palliative), biological therapy, or other novel agent
* Prior anti-cancer therapy within 2 weeks prior to study enrollment
* Prior treatment with a MYC inhibitor
* Known severe hypersensitivity to OMO-103 or to any excipient of these medicinal products, or history of allergic reactions attributed to compounds of similar chemical or biologic composition
* Major surgery within 6 weeks prior to enrollment
* Uncontrolled intercurrent illness including symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, and myocardial infarction within 3 months of initiating study intervention
* History of psychiatric illness likely to interfere with ability to comply with protocol requirements or give informed consent
* Participant is pregnant or breastfeeding, or expecting to conceive or father children within the projected duration of the trial, starting with the screening visit through 6 months after the last dose of trial treatment
* Judgment by the investigator that the patient should not participate in the study if the patient is unlikely to comply with study procedures, restrictions and requirements