indoximod + pembrolizumab

**Indoximod + pembrolizumab** is an investigational combination therapy for advanced melanoma and potentially other solid tumors. **Indoximod** is a small-molecule inhibitor of the indoleamine 2,3-dioxygenase (IDO) pathway, which cancer cells use to suppress immune responses by breaking down tryptophan, leading to local immunosuppression. By mimicking tryptophan, indoximod helps restore the "tryptophan sufficiency" signal, reversing immune suppression and enhancing the ability of immune cells to attack tumors. **Pembrolizumab** is a monoclonal antibody checkpoint inhibitor targeting the programmed cell death protein 1 (**PD-1**) receptor on T cells, blocking inhibitory signals to promote immune-mediated tumor cell killing. The combination has shown higher overall response rates compared to pembrolizumab alone in Phase II studies on unresectable or metastatic melanoma patients, with a generally well-tolerated safety profile and no significant increase in severe toxicity[1][2][3][5][6][7][8].