Background: REACH (NCT01140347) and REACH-2 (NCT02435433) studied ramucirumab (RAM) in pts with advanced hepatocellular carcinoma (HCC) following sorafenib; REACH-2 enrolled pts with baseline alpha-fetoprotein (AFP) ≥400 ng/mL, and met its primary endpoint of overall survival (OS) for RAM vs placebo. This post-hoc analysis examined radiological progression patterns (RPP) incidence every 6 weeks per RECIST v1.1, and if RPP were related to OS and post-progression survival (PPS). Methods: Pts with advanced HCC, Child-Pugh A, and ECOG PS 0-1 with prior sorafenib were randomized (REACH 1:1; REACH-2 2:1) to receive RAM 8 mg/kg or placebo Q2W. Among pts with ≥1 RPP (new extrahepatic lesion [NEH], new intrahepatic lesion [NIH], extrahepatic growth [EHG], or intrahepatic growth [IHG]), results were analyzed by trial and for pooled individual patient data of REACH-2 and REACH (AFP ≥400 ng/mL). Cox models evaluated treatment effect of RPP on OS, and prognostic implications of RPP on OS (adjusting baseline ECOG PS, AFP, macrovascular invasion, arm) and on PPS (adjusting ECOG PS, AFP at progression). Results: RPP incidence in the pooled population was: NEH 39%; NIH 24%; EHG 39%; IHG 37%. When examining NEH vs other RPP, PPS was worse among those with NEH in REACH (HR 2.33, 95% CI 1.51, 3.60), REACH-2 (HR 1.49, 95% CI 0.72, 3.08), and the pooled data (HR 1.75, 95% CI 1.12, 2.74). Use of post-discontinuation therapy may have influenced results. OS was also significantly reduced in those with NEH across studies (Table). RAM provided OS benefit in the pooled population, including pts with NEH (HR 0.56, 95% CI 0.39, 0.80). Conclusions: Acknowledging limitations of post-randomization RPP analysis, the emergence of NEH on RAM or placebo may be an independent poor prognostic factor for PPS. The impact of RAM on OS was consistent across all RPP subgroups. Clinical trial information: NCT01140347 and NCT02435433