P-219: Relationship between corneal exam findings, best-corrected visual acuity, and ocular symptoms in patients with relapsed or refractory multiple myeloma receiving belantamab mafodotin

Abstract

Background Belantamab mafodotin (belamaf; GSK2857916) is a B-cell maturation antigen (BCMA)-targeting antibody–drug conjugate approved in the United States and European Union as a monotherapy for heavily pretreated adult patients with relapsed or refractory multiple myeloma (RRMM). Ocular events (OEs) during the pivotal DREAMM-2 trial (NCT03525678) included corneal exam findings (superficial punctate keratopathy and/or microcyst-like epithelial changes), decline in best-corrected visual acuity (BCVA), and ocular symptoms. Dose reductions or delays based on corneal exam findings and BCVA were used to manage OEs. Here we performed a post hoc investigation of relationships between corneal exam findings, BCVA changes, and patient-reported ocular symptoms to explore if BCVA decline and symptoms could guide dosing, rather than corneal exams. Methods Eye evaluations (including a corneal exam and BCVA assessment of Snellen visual acuity) were performed on all patients receiving single-agent belamaf (2.5 mg/kg) by ophthalmologists at baseline and prior to each belamaf dose. Changes in the corneal epithelium (keratopathy) and BCVA were both assessed as per protocol-defined criteria and assessment of grade (GR) was based on the worse eye. BCVA grading was relative to baseline. Patient-reported ocular symptoms were reported as per the Common Terminology Criteria for Adverse Events. Results In 12.5% of eye evaluations, GR 3–4 keratopathy was associated with minimal or no (GR ≤1) BCVA changes. When patient-reported ocular symptoms were also considered, GR 3–4 keratopathy with GR ≤1 BCVA changes and no ocular symptoms was observed in only 7.5% of evaluations. Mild or no (GR ≤2) keratopathy was associated with GR ≤1 BCVA changes in 59.5% of evaluations, or in 38.8% of evaluations with no ocular symptoms reported. Overall, GR 3–4 keratopathy was found in 24.9% of evaluations; by contrast, patients had GR 2–4 BCVA changes or ocular symptoms in 53.6% of evaluations. Conclusions These findings suggest that BCVA changes and ocular symptoms should be further investigated to determine if they can be used as potential surrogate markers (eg, frequency of eye examinations based on symptoms) for the management of belamaf dosing to potentially reduce the burden on patients and healthcare professionals. Funding Source GSK (205678; NCT03525678). Drug linker technology licensed from Seagen Inc.; mAb produced using POTELLIGENT Technology licensed from BioWa. Encore Statement ©2021 American Society of Clinical Oncology, Inc. Reused with permission. This abstract was accepted and previously presented at the 2021 ASCO Annual Meeting. All rights reserved. Belantamab mafodotin (belamaf; GSK2857916) is a B-cell maturation antigen (BCMA)-targeting antibody–drug conjugate approved in the United States and European Union as a monotherapy for heavily pretreated adult patients with relapsed or refractory multiple myeloma (RRMM). Ocular events (OEs) during the pivotal DREAMM-2 trial (NCT03525678) included corneal exam findings (superficial punctate keratopathy and/or microcyst-like epithelial changes), decline in best-corrected visual acuity (BCVA), and ocular symptoms. Dose reductions or delays based on corneal exam findings and BCVA were used to manage OEs. Here we performed a post hoc investigation of relationships between corneal exam findings, BCVA changes, and patient-reported ocular symptoms to explore if BCVA decline and symptoms could guide dosing, rather than corneal exams. Eye evaluations (including a corneal exam and BCVA assessment of Snellen visual acuity) were performed on all patients receiving single-agent belamaf (2.5 mg/kg) by ophthalmologists at baseline and prior to each belamaf dose. Changes in the corneal epithelium (keratopathy) and BCVA were both assessed as per protocol-defined criteria and assessment of grade (GR) was based on the worse eye. BCVA grading was relative to baseline. Patient-reported ocular symptoms were reported as per the Common Terminology Criteria for Adverse Events. In 12.5% of eye evaluations, GR 3–4 keratopathy was associated with minimal or no (GR ≤1) BCVA changes. When patient-reported ocular symptoms were also considered, GR 3–4 keratopathy with GR ≤1 BCVA changes and no ocular symptoms was observed in only 7.5% of evaluations. Mild or no (GR ≤2) keratopathy was associated with GR ≤1 BCVA changes in 59.5% of evaluations, or in 38.8% of evaluations with no ocular symptoms reported. Overall, GR 3–4 keratopathy was found in 24.9% of evaluations; by contrast, patients had GR 2–4 BCVA changes or ocular symptoms in 53.6% of evaluations. These findings suggest that BCVA changes and ocular symptoms should be further investigated to determine if they can be used as potential surrogate markers (eg, frequency of eye examinations based on symptoms) for the management of belamaf dosing to potentially reduce the burden on patients and healthcare professionals.