TPS10124 Background: Nab-paclitaxel/gemcitabine ( nab-P/gem) is an effective 1st line regimen for metastatic pancreatic ductal adenocarcinoma (mPDAC). Elderly mPDAC patients (pts) may as well benefit from nab-P/gem. Geriatric assessments to evaluate the functional reserve of these pts may allow individualization of treatment. Therefore, the aim of this study is to determine whether comprehensive geriatric assessments (CGAs) can predict the benefit from combined nab-P/gem therapy for elderly mPDAC pts in 1st line. A stratified treatment approach shall result in patient groups with a stable or improving CGA performance during the 1st cycle of treatment. Methods: GrantPax (NCT02812992) is a multicenter, open label phase 4 interventional trial with stratified parallel treatment groups (n = 45 per arm). The hypothesis is that individualized assessment directed treatment algorithms identify elderly pts (≥70 yrs), who benefit from combined nab-P/gem therapy. The study uses a CGA to stratify pts as GOGO, SLOWGO or FRAIL. Depending on test outcome, pts receive chemotherapy (GOGO: nab-P/gem; SLOWGO: gem mono) or best supportive care (FRAIL). After 1st cycle of chemotherapy (4 wks) a CGA and safety assessment will be performed to assign pts to their definite treatment arm. The primary objective is that CGA-stratified pts do not decline in their CGA performance in response to chemotherapy, measured as a loss of 5 points or less in Barthels activities of daily living (ADL1 vs. ADL2 during CGA core assessment). The expected proportion of pts with ADL decline in each treatment group is 6%. Under this assumption it shall be shown with 80% power at one-sided significance level alpha of 0.05 that the proportion of pts with functional decline is less than 20% (n = 43 per group; ADL decline: n = 2 per group). Secondary endpoints are CGA scores during the course of therapy (CGA1-4), response rates, safety, survival rates, duration of treatment, cumulative dose, quality of life and discrepancy between CGA strata estimation by the investigator and true CGA assessment. GrantPax is the first trial realizing a CGA-driven treatment to individualize cancer therapy for elderly pts. Clinical trial information: NCT02812992.