Summary

Multiple myeloma (MM) is an incurable malignancy and accounts for 1 percentage (%) of all
cancers and for 10% of all hematologic malignancies. Participants with relapsed/refractory
multiple myeloma (RRMM) will be included in this study, to evaluate the efficacy and safety
of belantamab mafodotin (GSK2857916) monotherapy. Participants will be treated with
belantamab mafodotin monotherapy until disease progression (PD) or unacceptable toxicity and
will be followed for Progression Free Survival and Overall survival. The participants will be
randomized to receive either frozen belantamab mafodotin at the dose of 2.5 milligram per
kilogram (mg/kg) or 3.4 mg/kg administered Intravenously (IV). There will be an independent
cohort of participants who will receive a lyophilized configuration of belantamab mafodotin.
For participants who discontinued from the study other than Progressive disease (PD), disease
evaluation will continue to be performed at 3-week intervals until confirmed PD, death, start
of a new anticancer treatment, withdrawal of consent, or end of the study whichever occurs
first.