⁃ I 1. Male or female who is 12 years of age or older at the time of signed informed consent.

⁃ I 2. Patients with histologically or cytologically confirmed unresectable or metastatic Stage IIIb through IV/M1a through M1d cutaneous melanoma, as per AJCC staging system, 8th edition).

⁃ I 3. Confirmed disease progression (PD) on an anti-PD-1 antibody treatment and an anti-CTLA-4 antibody treatment, administered as either a combination regimen (eg, nivolumab + ipilimumab) or in sequence.

• Treatment with prior anti-PD-1 therapy must have continued for a minimum of 8 weeks (note: treatment with prior pembrolizumab therapy when administered every 6 weeks must have continued for a minimum of 12 weeks \[ie, 2 treatment cycles\]). Any number of doses of prior anti-CTLA-4 therapy may have been administered in combination with an anti-PD-1. The anti-PD-1-containing therapy must be the immediate prior line of treatment before randomization (for patients with BRAF mutation, see I 4).

• Patients who in the physician's judgement are not candidates for treatment with an anti-CTLA-4 antibody (eg, due to documented clinically significant comorbidities or history of immune-related adverse events) are eligible for the study if they have confirmed PD on an anti-PD-1 antibody (including unresectable disease relapse during adjuvant therapy or \< 6 months from completion of adjuvant therapy).

• Disease progression must have been confirmed and documented using clinical or radiological assessment by 2 assessments at least 4 weeks apart while being treated with an anti-PD-1 antibody and an anti-CTLA-4 antibody. Radiological confirmation of PD can occur during the Screening period for this study. Treatment with prior anti-PD-1 therapy must have continued from the time of initial tumor progression until confirmation of PD (ie, such that no doses of anti-PD-1 therapy were missed).

⁃ Note: If radiographic progression at the initial scan where PD was documented is accompanied by clear clinical progression, defined as a decline in performance status directly attributed to disease or increased disease-related symptoms, anti-PD-1 therapy does not need to continue. For patients with documented PD while on adjuvant therapy with an anti-PD-1 therapy, a confirmatory biopsy can be used in place of a confirmatory scan.

⁃ I 4. Has documented BRAF V600 mutation status or must consent to BRAF V600 mutation testing per local institutional standards during the Screening period. Patients with BRAF mutation should have received prior BRAF-directed therapy (with or without a MEK inhibitor) prior to randomization, unless deemed not clinically indicated at Investigator's discretion due to concurrent medical condition or prior toxicity.

⁃ Note: Prior exposure to BRAF-directed therapy (with or without a MEK inhibitor) includes treatment in the adjuvant setting. One line of BRAF-directed therapy (with or without a MEK inhibitor) can be the most recent systemic treatment administered before randomization.

⁃ I 5. Has least 1 measurable tumor of ≥ 1 cm in longest diameter (or shortest diameter for lymph nodes) and injectable lesion(s) of at least 1 cm in longest diameter.

⁃ I 6. Has adequate hematologic function, including:

• White blood cell (WBC) count ≥ 2.0 × 109/L

• Absolute neutrophil count (ANC) ≥ 1.5 × 109/L

• Platelet count ≥ 75 × 109/L

• Hemoglobin ≥ 8 g/dL (without packed red blood cell \[RBC\] transfusion within 2 weeks of dosing)

⁃ I 7. Has adequate hepatic function, including:

• Total bilirubin ≤ 1.5 × upper limit of normal (ULN; \< 2.0 × ULN for patients with known Gilbert syndrome or liver metastases)

• Aspartate aminotransferase (AST) and alanine aminotransferase (ALT) ≤3.0 × ULN (or ≤ 5.0 × ULN, if liver metastases are present)

• Alkaline phosphatase (ALP) ≤ 2.5 × ULN (or ≤ 5.0 × ULN, if liver or bone metastases are present) I 8. Has adequate renal function, defined as serum creatinine ≤ 1.5 × ULN or creatinine clearance ≥ 3 0 mL/minute/1.73 m2 (measured using Chronic Kidney Disease Epidemiology Collaboration \[CKD-EPI\] formula).

⁃ I 9. Prothrombin time (PT) ≤ 1.5 × ULN (or international normalization ratio \[INR\] ≤ 1.3) and partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT) ≤ 1.5 × ULN. Note: Patients who are on chronic anticoagulant therapy may be randomized if the target INR is ≤ 2.5. For patients requiring deep injection of VO, the INR must be \<1.5 at the time of injection.

⁃ I 10. ECOG performance status (PS) 0 to 1 for patients 18 and older or a Lansky PS ≥ 80 for patients 12 to 17 years of age.

⁃ I 11. Life expectancy of at least 3 months. I 12. Female and male patients of reproductive potential must agree to avoid becoming pregnant or impregnating a partner and adhere to highly effective contraception requirements during the treatment period and for at least 6 months after the last dose of any study treatment.

⁃ I 13. Women of childbearing potential must have a negative serum beta-human chorionic gonadotropin (β-hCG) test with a minimum sensitivity of 25 IU/L or equivalent units or β hCG within 7 days before the first dose of study treatment.

⁃ I 14. Capable of giving signed informed consent which includes willingness to comply with the requirements and restrictions listed in the informed consent form (ICF)