(NSO-04) Patient Perspectives of Receiving Out-patient Step-up Dosing with Bispecific Antibodies (BsAb) for Relapsed Multiple Myeloma (MM)

Delivering bispecific antibodies (BsAb) in outpatients (OP) vs an inpatient setting is often preferred by multiple myeloma (MM) patients and improves inpatient bed capacity. However, these therapies require close monitoring for side effects particularly cytokine release syndrome (CRS) and immune effector cell associated neurotoxicity syndrome (ICANS) which many patients may not be familiar with. This may pose potential barriers to OP dosing and we therefore sought to evaluate the experience of MM patients who received OP step-up dosing to identify how best to support patients.

Methods:

Patients were treated in ambulatory care (AC) and stayed in designated accommodation located 170 metres from the treating centre with a caregiver. All patients were educated regarding toxicities including CRS and ICANS.  Patients were prospectively interviewed later in treatment using semi-structured interviews. Interview transcripts were analysed using the Framework Method, a systematic and flexible approach for analysing qualitative data.

Results:

Six patients (age range 51 to 74; two males) received step-up dosing in AC. This was a heavily pre-treated cohort (median prior lines: 5, range: 4-11). Four patients felt they had been given adequate information and education by clinicians and pharmacists about logistics of treatment in AC, toxicities and when to seek medical attention. All patients preferred receiving BsAb in AC due to increased freedom and privacy compared to being an inpatient. Two expressed feeling anxious and more alone in AC, but all patients felt they were adequately supported by nursing teams whilst being treated in AC.

Four of the six patients required transfer to hospital due to G1 CRS (fever) within 2 days of treatment (range:2 hours-3 days) and 2 further developed G2 CRS requiring tocilizumab and dexamethasone. No patients developed ICANS or G3 CRS. All patients interviewed were anxious about toxicity, particularly CRS but most (n=4) felt their side effects were mild/moderate. Four patients were admitted via Emergency Department (ED) with long waits, causing anxiety and frustration. Median inpatient stay was 10 days (range:5-13) and all patients completed step-up dosing as an inpatient thereafter.

Notably, 3 caregivers voiced pressure from the responsibility of caring for and undertaking monitoring for their relative whilst in AC compared to inpatient care. Overall, all patients interviewed felt that delivery of BsAb in AC was well managed and 3 would be happy to have treatment again in AC, whilst the others were happy to receive treatment in either setting.

Conclusions:

Patient feedback from this study suggests that step-up dosing of BsAb in AC is acceptable and provides advantages eg. greater freedom and privacy. Further work is needed to improve patient experience by streamlining admission pathways, particularly via ED and improving support and education to caregivers.