Acasunlimab is an investigational medication being tested in this trial. It is designed to help the body’s immune system fight cancer cells. This medication works by targeting specific proteins that help cancer cells hide from the immune system, allowing the body’s natural defenses to recognize and attack the melanoma.

Pembrolizumab is a type of immunotherapy medication that helps the immune system fight cancer. It works by blocking a protein called PD-1, which prevents the immune system from attacking cancer cells. By blocking this protein, pembrolizumab allows the immune system to better recognize and destroy melanoma cells. In this trial, it is being tested in combination with acasunlimab to see if the two medications work better together than acasunlimab alone.

Cutaneous Melanoma – Cutaneous melanoma is a type of skin cancer that develops from melanocytes, which are the cells that produce pigment in the skin. The disease begins when these cells start growing abnormally and uncontrollably. In its early stages, melanoma appears as an unusual mole or dark spot on the skin that may change in size, shape, or color. As the disease progresses, cancer cells can grow deeper into the layers of the skin. Without intervention, the abnormal cells may spread to nearby lymph nodes and other parts of the body through the bloodstream or lymphatic system. Advanced melanoma can affect various organs including the lungs, liver, brain, and bones.

Relapsed or Refractory Melanoma – Relapsed melanoma occurs when the cancer returns after a period of improvement or remission following previous treatment. Refractory melanoma refers to cases where the cancer does not respond to treatment or continues to grow despite therapy. In both situations, the cancer cells have either survived the initial treatment or developed resistance to it. The disease may reappear in the same location as the original tumor, in nearby tissues, or in distant parts of the body. These forms of melanoma can be more challenging to manage as the cancer cells have demonstrated the ability to evade or resist therapeutic approaches.

Locally Advanced Unresectable Melanoma – Locally advanced unresectable melanoma is a stage of skin cancer where the tumor has grown extensively in the area where it started but cannot be completely removed through surgery. The cancer may have spread to nearby skin, tissues, or lymph nodes in a way that makes surgical removal impossible or unsafe. This condition typically includes Stage IIIB, IIIC, or IIID melanoma classifications. The tumor may be too large, located in a difficult area, or involve critical structures that prevent safe surgical removal. Despite being locally advanced, the cancer has not yet spread to distant organs in the body.

Metastatic Melanoma – Metastatic melanoma, also known as Stage IV melanoma, occurs when skin cancer cells have spread from the original tumor to distant parts of the body. The cancer cells travel through the lymphatic system or bloodstream to reach other organs. Common sites where melanoma spreads include the lungs, liver, bones, and brain, though it can affect virtually any organ. At this stage, multiple tumors may be present in different locations throughout the body. The disease represents the most advanced form of melanoma progression.