A Study to Evaluate Safety, Tolerability and Preliminary Activity of AGX101 in Participants With Advanced Solid Tumors

Inclusion Criteria: * Histologically confirmed unresectable, locally advanced, or metastatic solid tumors. * Refractory to or relapsed after all standard therapies known to provide proven clinical benefit, unless the patient is not a candidate for standard treatment, there is no standard treatment, or the patient refuses standard treatment after expressing an understanding of all available therapies with proven clinical benefit * Willing to authorize use of existing archival tissue, unless otherwise discussed with Sponsor * Time since the last dose of prior therapy to treat underlying malignancy (including other investigational therapy): Systemic cytotoxic chemotherapy: ≥ the duration of the most recent cycle of the previous regimen (with a minimum of 2 weeks for all, except 6 weeks for systemic nitrosourea or systemic mitomycin-C); Biologic therapy (eg, antibodies): ≥ 3 weeks; Small molecule therapies: ≥ 5 × half-life * Have an ECOG performance status of 0 to 1 * Have adequate organ function * LVEF ≥ 50%, as determined on cardiac ECHO or cardiac multiple-gated acquisition (MUGA) scan * Highly effective contraception for both male and female patients throughout the study Exclusion Criteria: * Colorectal cancer patients with an unresected primary colorectal tumor and non-small-cell lung cancer with predominant squamous histology (ie, squamous cell carcinoma of the lung) are excluded unless otherwise discussed and approved by Sponsor * Clinically unstable central nervous system (CNS) tumors or brain metastasis (stable and/or asymptomatic CNS metastases allowed) * Have not recovered to ≤ Grade 1 or baseline from all AEs due to previous therapies (patients with ≤ Grade 2 neuropathy, endocrine-related irAEs, or other AEs may be eligible after discussion with the Sponsor) * Has an active vasculitis that has required systemic treatment in the past 2 years prior to starting study treatment * Significant (ie, ≥ Grade 2) ocular disturbances * Variceal bleeding within 6 months prior to treatment, currently untreated or incompletely treated varices with bleeding, or who otherwise are at a high risk of bleeding * Any other concurrent antineoplastic treatment except for allowed local radiation of lesions for palliation (to be considered non-target lesions after treatment) and hormone ablation * Uncontrolled or life-threatening symptomatic concomitant disease, including known symptomatic HIV positive with an AIDS defining opportunistic infection within the last year, known symptomatic active hepatitis B or C, or known active tuberculosis * Has undergone a major surgery within 3 weeks prior to starting study treatment or has inadequate healing or recovery from complications of surgery prior to starting study treatment * Has received prior radiotherapy within 2 weeks prior to starting study treatment * Has or had a potentially life-threatening second malignancy requiring systemic treatment within the last 3 years, or which would impede evaluation of treatment response * Clinically significant cardiovascular disease * Patients on a potent CYP3A inhibitor or CPY3A inducer who cannot be changed to another medication * Has an active infection requiring concurrent systemic antibiotic therapy * A woman of child-bearing potential (WOCBP) who has a positive pregnancy test prior to treatment * Is breastfeeding or expecting to conceive or father children within the projected duration of the study