DREAMM12

Belantamab mafodotin (GSK2857916) is an antibody-drug conjugate (ADC) containing humanized anti- B-cell maturation antigen (BCMA) monoclonal antibody (mAb). Renal impairment is a major complication of multiple myeloma (MM) and majority of MM participants are either at risk or already have renal dysfunction at initial diagnosis. The purpose of this study is to assess the pharmacokinetics (PK), safety, and tolerability of belantamab mafodotin monotherapy in participants with RRMM, who have had at least 3 lines of prior treatment and have either normal or impaired renal functions. The study will consist of two parts: part 1 will include participants with normal/mildly impaired renal function and severe renal impairment and part 2 will include participants with end-stage renal disease (ESRD), where participants are either not undergoing or require hemodialysis. Participants will be administered GSK2857916 at a dose of 2.5 milligram per kilogram (mg/kg) intravenously once in three weeks (Q3W) dosing in Part 1. Based on the Part 1 Safety/Pharmacokinetic (PK) data, Part 2 participants will be administered the dose of either 2.5 mg/kg or 1.9 mg/kg (or other adjusted dose). Participants will be treated with GSK2857916 monotherapy until confirmed disease progression, death, unacceptable toxicity, withdrawal of consent, or end of study, whichever occurs first. This study will include a screening phase, treatment phase, and follow- up phase. The total duration of the study is approximately up to 48 months.