PDCD1 and neoplasm: Despite demonstrating antitumor activity and synergistic tumor reduction in xenograft and syngeneic murine models when combined with anti-PD-1 therapy [140], the PPARα inhibitor TPST-1120 in combination with nivolumab in a first-in-human phase 1 study across multiple solid tumor types did not yield positive results in three of four patients with HCC experiencing progression of disease [48].