IMA901 Multipeptide Vaccine Randomized International Phase III Trial (IMPRINT): A randomized, controlled study investigating IMA901 multipeptide cancer vaccine in patients receiving sunitinib as first-line therapy for advanced/metastatic RCC.

TPS183 Background: IMA901 is a therapeutic vaccine composed of multiple naturally presented tumor-associated peptides (TUMAPs). Previous data have indicated that vaccination with IMA901 results in a relevant clinical benefit, ie. advanced RCC patients with detectable T cell responses against TUMAPs had a better disease control and overall survival as compared to patients without such responses. Furthermore, pre-treatment with a single dose of cyclophosphamide (CY; 300mg/m2) was able to reduce regulatory T cells (Treg) and improve survival compared to patients vaccinated without prior CY, resulting in considerably longer median survival than expected (>24 months in second-line cytokine pre-treated mRCC patients). Treatment with IMA901 was overall well tolerated with most AE being local side effects. Suntinib is a standard treatment for mRCC and was approved based on the improvement of PFS. It has been speculated that sunitinib may also favorably alter immune regulation via reduction of Treg and myeloid-der...