GRWD5769

GRWD5769 is a first-in-class, orally bioavailable small molecule inhibitor of endoplasmic reticulum aminopeptidase 1 (ERAP1), developed by Grey Wolf Therapeutics for the treatment of advanced solid tumors. By inhibiting ERAP1, GRWD5769 modulates the peptide repertoire presented on MHC class I molecules on tumor cells, leading to the generation and presentation of novel or upregulated neoantigens. This mechanism drives de novo T cell responses against tumor cells and overcomes immune resistance mechanisms such as T cell exhaustion. Preclinical studies have demonstrated that ERAP1 inhibition with GRWD5769 diversifies the T cell receptor repertoire, upregulates immune gene markers associated with activated (non-exhausted) T cells, and enhances infiltration of T cells into tumors. Early clinical data from ongoing Phase 1/2 trials show dose-dependent target engagement, a favorable safety profile, and initial evidence of stable disease in some patients. The drug is also being evaluated in combination with PD-1 inhibitors like cemiplimab (Libtayo) to further enhance antitumor immunity[1][3][5][6][7].