RT Journal Article SR Electronic T1 36 Prognostic value and association with veliparib benefit of modeled CA-125 elimination kinetics (KELIM) in patients with newly diagnosed ovarian cancer: analysis from the VELIA/GOG-3005 study JF International Journal of Gynecologic Cancer JO Int J Gynecol Cancer FD BMJ Publishing Group Ltd SP A24 OP A25 DO 10.1136/ijgc-2020-IGCS.36 VO 30 IS Suppl 3 A1 B You A1 G Fleming A1 M Bookman A1 KN Moore A1 KD Steffensen A1 RL Coleman YR 2020 UL http://ijgc.bmj.com/content/30/Suppl_3/A24.abstract AB Introduction In VELIA (Phase 3), veliparib with carboplatin/paclitaxel (CP), followed by veliparib maintenance (veliparib-throughout) led to improved progression-free survival (PFS) vs CP alone (control). This exploratory analysis assessed the prognostic and predictive value of the modeled CA-125 elimination rate constant, KELIM.Methods KELIM was estimated from treatment-related pharmacodynamic modeling of CA-125 values. Median KELIM was used to define favourable (≥median)/unfavourable (<median) KELIM groups. Patients were analyzed by surgery type: primary (PDS) or interval (IDS) debulking surgery.Results In the IDS population (N=154), patients with favourable KELIM had a higher frequency of complete surgery vs unfavourable KELIM (51.9% vs 32.4%), confirming KELIM as a chemosensitivity marker. In both PDS (N=700) and IDS populations, median PFS was longer with favourable KELIM vs unfavourable KELIM, demonstrating a prognostic value. In the PDS population, median PFS was longer in the veliparib-throughout arm relative to control irrespective of KELIM (29.6 vs. 20.9 and 18.2 vs 15.4 months in favourable and unfavourable KELIM groups, respectively; figure 1). In the IDS population, median PFS was longer with veliparib-throughout vs control for patients with favourable KELIM only (29.3 vs 20.8 months; figure 2).Abstract 36 Figure 1 Progression-free survival in the veliparib throughout arm and the control arm for KELIM subgroups in the PDS populationAbstract 36 Figure 2 Progression-free survival in the veliparib throughout arm and the control arm for KELIM subgroups in the IDS populationConclusion In VELIA, KELIM was prognostic for PFS and IDS outcomes. Current data suggest KELIM may be associated with veliparib benefit. Ongoing analyses will explore how baseline characteristics contribute to KELIM predictive/prognostic value.