Relationship between corneal exam findings, best-corrected visual acuity (BCVA), and ocular symptoms in patients with relapsed or refractory multiple myeloma (RRMM) receiving belantamab mafodotin (GSK2857916; belamaf; BLENREP)

Context Belamaf is a B-cell maturation antigen-targeting antibody-drug conjugate approved in the US and EU for the treatment of RRMM. Ocular events (OEs) during the DREAMM-2 trial (NCT03525678) included corneal exam findings (punctate keratopathy and microcyst-like epithelial changes), BCVA changes, and ocular symptoms. Dose reductions or delays based on corneal exam findings and BCVA were used to manage OEs. Objective To study relationships between exam findings, BCVA changes, and patient-reported ocular symptoms in a post hoc analysis to explore if BCVA changes and symptoms alone could guide dosing. Methods Patients receiving single-agent belamaf (2.5 mg/kg) had eye evaluations (including a corneal exam and BCVA assessment of Snellen visual acuity) performed by ophthalmologists at baseline and prior to each dose. Changes in the corneal epithelium (Ker) and BCVA were assessed per protocol-defined criteria and assessment of grade was based on the worse eye. BCVA grading was relative to baseline. Patient-reported ocular symptoms were reported per the Common Terminology Criteria for Adverse Events. Results In 12.5% of eye evaluations Grade 3–4 Ker was associated with minimal or no (Grade ≤1) BCVA changes. When patient-reported ocular symptoms were also considered, only 7.5% of evaluations found Grade 3–4 Ker with Grade ≤1 BCVA changes or ocular symptoms. Mild or no (Grade ≤2) Ker was associated with Grade ≤1 BCVA changes in 59.5% of evaluations, or in 38.8% of evaluations with no ocular symptoms reported. Overall, Grade 3–4 Ker were found in 24.9% of evaluations; by contrast, patients had Grade 2–4 BCVA changes or ocular symptoms in 53.7% of evaluations. Conclusions BCVA changes and ocular symptoms should be further investigated to determine if they can be used as alternatives (e.g., frequency of eye examinations based on symptoms) for the management of belamaf dosing to potentially reduce the burden on patients and healthcare professionals. Funding GlaxoSmithKline (205678; NCT03525678). Drug linker technology licensed from Seagen Inc.; mAb produced using POTELLIGENT Technology licensed from BioWa. © 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.