Personalized Neo-Antigen Peptide Vaccine for the Treatment of Stage IIIC-IV Melanoma, Hormone Receptor Positive HER2 Negative Metastatic Refractory Breast Cancer or Stage III-IV Non-Small Cell Lung Cancer

This study is testing a personalized cancer vaccine made from your own tumor's unique mutations (called neoantigens), designed to teach your immune system to recognize and attack cancer cells. **You may be eligible if...** - You are 18 years or older - You have a solid tumor (any type) with at least one lesion large enough to biopsy - You have measurable disease that can be tracked on scans - You are in adequate general health (ECOG performance status 0–2) - You are able to provide tumor tissue for analysis to create your custom vaccine **You may NOT be eligible if...** - You have active brain metastases causing symptoms - You have serious autoimmune disease requiring ongoing treatment - You have active uncontrolled infections - Your organ function (liver, kidneys, blood counts) does not meet minimum requirements - You are pregnant or breastfeeding Talk to your doctor to see if this trial is right for you.