Effect of baseline geriatric and quality of life assessments on treatment outcomes in ECOG-ACRIN EA2186 (GIANT): A randomized phase II study of gemcitabine and nab-paclitaxel compared with 5-fluorouracil, leucovorin, and liposomal irinotecan in older

676 Background: Data is lacking to guide the care of vulnerable older adults (OA) with newly diagnosed metastatic pancreatic adenocarcinoma (mPDAC). EA2186 trial demonstrated poor outcomes among vulnerable OA with mPDAC treated with dose-reduced chemotherapy. To understand the factors driving treatment outcomes in this patient population, we analyzed the correlation between baseline geriatric and quality of life (QOL) assessments and treatment outcomes. Methods: Vulnerable OA ≥70 yo with mPDAC, ECOG PS 0-2 were enrolled. Vulnerability was defined by screening geriatric assessment (GA) demonstrating mild abnormalities in function, comorbidities, cognition, or age≥80y. Pts were randomized to Arm A: Gemcitabine (1000mg/m2) + Nab-Paclitaxel (125mg/m2) q14 days or Arm B: 5-Fluorouracil (2400mg/m2 46hr) + Leucovorin (400mg/m2) + Liposomal Irinotecan (50mg/m2) q14 days. GA and QOL evaluations were completed at baseline and 3 time points. Secondary endpoints of the study included evaluating the correlation between baseline GA, QOL and treatment outcomes. Regression models were used to evaluate the associations between baseline GA and QOL factors, survival and grade 3 or higher toxicity, with 80% power to detect doubling in grade 3 toxicity for GA/QOL measures. Results: 176 pts (88 per arm) enrolled with median age 77 (range 70-90), 24% ECOG-0, 64% ECOG-1 and 12% ECOG-2. Pts were deemed vulnerable by cognition (46%), age (36%) or comorbidities (31.4%), with 35% meeting vulnerability criteria in ≥2 domains. No significant difference was seen in median OS (4.7 vs. 4.4 months; p=0.72) or ≥grade 3 toxicity rate (45.6% vs. 58.7%; p=0.10) between arms A and B, respectively. Strong correlation was found between OS and baseline instrumental activities of daily living score (HR 0.84; p=0.02), nutritional scores (HR 0.82; p<0.0001), depression scores (HR 1.07; p=0.02), and scores of all QOL measures (HR 0.98; p<0.0001). No correlation was found between OS and comorbidity, cognition, and Activities of Daily Living scores. After adjustment for age and PS, only baseline WBC level (OR=0.35; p=0.0054), and depression scores (OR=1.20 per score unit; p=0.021) and to a lesser extent FACT-G score (OR=0.98 per score unit; p=0.061) were found to correlate with rates of ≥grade 3 toxicity. Conclusions: Baseline GA and QOL factors among vulnerable older adults with mPDAC correlate strongly with survival and treatment tolerance. Supportive care to address these factors may favorably affect outcomes in this patient population. Clinical trial information: NCT04233866 .