Association of losartan use with outcomes in metastatic pancreatic cancer patients treated with chemotherapy.

Abstract

e16738 Background: A phase II trial has shown improved efficacy of neoadjuvant therapy when combined with losartan (by remodeling desmoplasia) in locally advanced pancreatic ductal adenocarcinoma (PDA). However, role of losartan is unknown in metastatic PDA. We examined the relationship between the use of the angiotensin II receptor antagonist, losartan, at time of diagnosis with clinical outcomes in metastatic PDA pts that received chemo. Methods: We retrospectively evaluated 114 metastatic PDA pts treated at our center between Jan 2000 and Nov 2019. We compared OS, PFS, objective response rate (ORR), and disease control rate (DCR) between pts using losartan at time of cancer diagnosis and a control group of pts not on losartan. A subanalysis was performed based on losartan dose: 100mg dose versus control pts. and based on chemo: FOLFIRINOX or gemcitabine+abraxane. Results: Table shows baseline demographics. No significant difference was found in OS [p = 0.455] or PFS [p = 0.919] in pts on losartan (median 274d, 83d) vs control (median 279d, 111d) [p = 0.466]. No significant difference was found in ORR [p = 0.621] or in DCR [p = 0.497]. No significant difference was found in OS [p = 0.771] or PFS [p = 0.064] in losartan pts (median 347d, 350d) vs control (median 333d, 101d) treated with FOLFIRINOX. No significant difference was found in OS [p = 0.916] or PFS [p = 0.341] in losartan (median 312d, 69d) vs control (median 221d, 136d) [p = 0.916] treated with gemcitabine+abraxane. No significant difference was found in OS [p = 0.727] or PFS [p = 0.790] in 100mg losartan pts (median 261d, 84d) vs control (median 279d, 111d). Conclusions: Pts on losartan at time of diagnosis had no significant difference in OS, PFS, ORR, DCR than control pts. However, a subanalysis of pts treated with FOLFIRINOX revealed a longer PFS with losartan than control but did not meet statistical significance, likely due to small sample size. To confirm if the benefit of losartan + FOLFIRINOX seen in neoadjuvant setting for locally advanced cancer also applies to metastatic cancer, our findings need to be validated in a larger cohort. [Table: see text]