The study was terminated early due to discontinuation of development of the investigational program.

The goal of this clinical trial is to learn more about the side effects and best dose of AXN-2510 in adults with advanced solid tumors. The main questions it aims to answer are:

• What are the side effects of AXN-2510?
• Which is the best tolerated dose of AXN-2510?
• How long does AXN-2510 stay in your body?

Participants will receive AXN-2510 every 3 weeks. Participants will visit the clinic for checkups and tests several days during the first and third doses, and once every 3 weeks for other doses.

This is a phase 1 study where all adult participants will receive AXN-2510. There will be 2 increasing doses of AXN-2510 given to participants, the dose given depends on when a participant enters the study. Next will be enrollment of 20 participants at the different doses to obtain more information about side effects, tolerability, and if the drug is helping.

Inclusion Criteria:

• Confirmed diagnosis of an advanced or metastatic solid tumor that is relapsed or refractory following previous therapy, and for which there is no available standard therapy.
• Availability of PD-L1 Tumor Proportion Score (TPS) or Combined Positive Score (CPS); OR willingness to submit tumor tissue, if available, for central testing.
• Eastern Cooperative Oncology Group (ECOG) performance status of 0, 1, or 2.
• Age ≥ 18 years at the time of signing the informed consent.
• Adequate hepatic function.
• Adequate renal function.
• Adequate bone marrow function.
• Adequate blood clotting function

Exclusion Criteria:

• Active, untreated brain metastases or leptomeningeal disease requiring immediate local therapy, with some exceptions.
• Concurrent malignancy that is progressing or requires active treatment, with some exceptions.
• Received prior treatment within 5 half-lives or 4 weeks prior to starting AXN-2510, whichever is shorter (6 weeks for nitrosourea or mitomycin-C). Patients with prostate or breast cancer may continue concurrent hormone therapy.
• Current use of immune-suppressive medication at the time of study enrollment, with some exceptions.
• Uncontrolled hypertension defined as blood pressure of ≥ 160 mmHg systolic and/or ≥ 95 mmHg diastolic.
• Gross hemoptysis within 2 months of enrollment (defined as coughing up ≥ 0.5 teaspoons of fresh blood or small blood clots).
• Concurrent use of therapeutic anticoagulation or anti-platelet agents.
• History of perforation and/or fistula of the gastrointestinal tract, history of gastrointestinal obstruction (including incomplete intestinal obstruction requiring parenteral nutrition), acute gastrointestinal bleeding within 6 months before enrollment, or extensive bowel resection within 6 months prior to enrollment.
• History of stroke, transient ischemic attack, or clinically significant thromboembolic event within 6 months prior to enrollment.
• Tumors with radiographic evidence of blood vessel invasion, central necrosis or intratumor cavitation, encasement of organs (e.g. heart, trachea, esophagus, central bronchi) or major blood vessels (e.g. central pulmonary artery, central pulmonary veins, aorta, brachiocephalic artery, common carotid artery, subclavian artery, superior vena cava).
• Impaired cardiac function or significant diseases.
• History of pulmonary fibrosis or interstitial pneumonia, pneumoconiosis, chemical pneumonia, interstitial lung disease requiring steroids, or other diseases causing severe impairment of lung function.
• Unresolved toxicity higher than Grade 1 CTCAE v5 (or most current version) attributed to any prior therapy or procedure at Screening, with exceptions for alopecia or Grade 2 neuropathy.
• Any prior Grade 4 immune-mediated adverse event (imAE) or Grade 3 imAE requiring steroid treatment while receiving immunotherapy that has been documented within the 12 months prior to the enrollment period.
• Known human immunodeficiency virus (HIV) or acquired immune deficiency syndromes. Note: well-controlled HIV will be allowed.
• Positive hepatitis B surface antigen and/or hepatitis B core antibody (participants with negative polymerase chain reaction assay are permitted with appropriate antiviral therapy). If a hepatitis test was conducted and had a negative result within 30 days of enrollment, an additional test is not required at screening.
• Active hepatitis C infection with positive viral loads. Participants who have been treated for hepatitis C infection can be included if they have documented sustained virologic response of ≥ 12 weeks. If a hepatitis test was conducted and had a negative result within 30 days of enrollment, an additional test is not required at screening.
• Known history of any grade hypersensitivity reactions (despite appropriate premedication) to any known components of AXN-2510 or required premedication.
• Women who are pregnant or lactating.
• Has a history or current evidence of any condition, therapy, or laboratory abnormality that in the opinion of the investigator, might confound the results of the trial.

Testing of samples may occur late in the study, and may not be available during patient treatment.