Participants in BVd arm must have received this drug in combination with belantamab mafodotin in first or second relapse. Doses, dose reductions, increased spacing between doses and number of total infusions will be recorded.

All participants evaluated in this study must have received this drug as salvage therapy in first or second relapse. Doses, dose reductions, increased spacing between doses and number of total infusions will be recorded.

Participants in BPd arm must have received this drug in combination with belantamab mafodotin in first or second relapse. Doses, dose reductions, increased spacing between doses and number of total infusions will be recorded.

The ECOG Performance Status Scale describes a patient's level of functioning in terms of their ability to care for themself, daily activity, and physical ability (walking, working, etc.).

Grades:

0: Fully active, able to carry on all pre-disease performance without restriction

1. Restricted in physically strenuous activity but ambulatory and able to carry out work of a light or sedentary nature, e.g., light house work, office work
2. Ambulatory and capable of all selfcare but unable to carry out any work activities; up and about more than 50% of waking hours
3. Capable of only limited selfcare; confined to bed or chair more than 50% of waking hours
4. Completely disabled; cannot carry on any selfcare; totally confined to bed or chair
5. Dead

Extramedullary disease is defined as an aggressive form of multiple myeloma characterized by the presence of soft-tissue plasmacytomas that result from hematogenous spread

Plasma cell leukemia is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells; diagnosis is based upon the percentage (≥20%) and absolute number (≥2 × 109/L) of plasma cells in peripheral blood. This outcome aims to annotate if the particpiant has a canonical MM (between 10% and 19% of clonal plasma cells in bone marrow) or the rare leukemized variant of MM, which is also known as plasma cell leukemia (≥20% clonal plasma cells).

This outcome aims to annotate if the participant has high-risk MM.

High-risk MM can be measured by a) beta 2-microglobulin (Sβ2M) levels, or by b) tumour genetic alterations:

1. High-risk is considered when Sβ2M>=5.5mg/L (if creatinin <1.2mg/dL).

2. High-genetic risk in MM (Avet-Loiseau H J Clin Oncol 2025) is defined as the presence of any of the following:

   • Deletion of 17p in >20% of sorted plasma cells
   • TP53 mutation
   • Biallelic deletion of 1p32
   • 2 alterations of the following: t(4;14), t(14;16) or t(14,20); or Gain/amplification of 1q; or monoallelic del 1p32

This outcome aims to annotate if the participant shows kideny disfunction or impairment at any time during treatment. Kidney or renal impairment is defined as creatinine clearance below 40 mL/min due to myeloma.

This outcome aims to annotate if the participant shows kideny disfunction or impairment at any time during treatment. Kidney or renal impairment can also be evaluated by serum creatinine and this happens when serum creatinine is above 2 mg/dL due to myeloma.

This outcome aims to annotate if the participant shows kidney failure at disease progression. Kidney failure is defined as an estimated glomerular filtration rate (eGFR) below 15 mL/min.

Tumoral load refers to the amount of disease detected at any time. It will be measured by the number of circulating tumour cells in peripheral blood (cells/L).

Tumoral load refers to the amount of disease detected at any time. It will be measured by serum beta-2-microglobulin levels (mg/L)

This outcome aims to annotate if the participant shows bone lytic lesions at any time during treatment. Lytic lesions are lesions that replace normal bone or with a vast proportion showing a lower density or attenuation than the normal bone. These lesions are characterized either by the replacement of bone matrix by other types of tissue including soft tissue, fluid or fat. These lytic lesions are caused by MM cells and are detected and accounted by radiography.

Annotation of the treatments received by each patient before the treatment with belantamab combinations analyzed in this study.

Annotation of the number of treatments received by each patient before the treatment with belantamab combinations analyzed in this study, and what patients' duration of response was (defined in months).

First line treatment refers to the treatment the patient received at diagnosis (in de novo MM status)

Measured in date (dd/mm/yyyy)

Measured in date (dd/mm/yyyy)

Measured in date (dd/mm/yyyy)

This outcome will annotate the patients' medical history before administering any belantamab combination including:

• Lung disease
• Heart disease
• Diabetes
• Other

Measured in dd/mm/yyyy for each drug of the belantamab combinations

The dose of each drug of the belantamab combinations will be annotated

Dose reductions for each drug of the belantamab combinations will be annotated

The reason for dose reductions for each drug of the belantamab combinations will be annotated

The time frame (in days) of any drug delay between drug doses for each drug of the belantamab combinations will be annotated

The new time frame (in days) between doses of any drug for each drug of the belantamab combinations will be annotated

Defined as the percentage of patients with confirmed partial response or better (i.e., partial response, very good partial response, complte remission, and strict complete response), according to International Myeloma Working Group 2016 or later criteria, if possible, and clinician's notes otherwise.

Defined as defined as the time in months from the first belantamab mafodotin infusion to the date of the first documented disease progression or death, whichever occurs first.

Defined as defined as the time from the first infusion of belantamab mafodotin (start date) until the date of death from any cause.

Defined as time from the first infusion of belantamab mafodotin to the date of disease progression (second relapse) or death (whichever occurs first), documented after initiation of new anti-myeloma therapy.