A phase I clinical trial has just begun for an experimental vaccine that shrinks melanomas in mice. The vaccine combines tumor proteins with an immune system booster. These active components are bound together with the material used to make dissolvable stitches, forming an aspirin-sized disk that is implanted under the skin. In a pre-clinical study, these dissolving vaccine implants completely eradicated melanomas in half of the mice treated. The new trial to test this treatment in people is currently accepting participants.