A Phase II, Open-Label Study of an Accelerated Infusion Rate of Daratumumab in Patients With Relapsed and Refractory Multiple Myeloma.

INTRODUCTION/BACKGROUND: Daratumumab is an anti-CD38 monoclonal antibody initially approved as a single agent for the treatment of relapsed and refractory multiple myeloma. The infusion-related reactions (IRRs) commonly seen with intravenous daratumumab have been managed by prolonging the first infusion, temporarily stopping/slowing the rate if reactions occur and using adequate pre- and post-infusion medications. Several retrospective studies have evaluated shorter infusions after ≥ 2 prior doses administered at the standard rates. Although the shorter infusions were well-tolerated, patients in these reports were given heterogeneous daratumumab regimens and had often already received multiple doses at the longer standard rates. PATIENTS AND METHODS: CMRG-009 is a prospective study designed to demonstrate the safety of accelerated daratumumab infusions commencing with the second dose. After an initial dose on Cycle 1 Day consisting of 8 mg/kg over 4 hours, all subsequent doses were given over 90 minutes. RESULTS: No grade 3 IRRs were observed with the 90-minutes infusions. Both the safety profile and anti-myeloma effects were otherwise similar to those observed with other single agent daratumumab studies using longer infusion times. CONCLUSION: This is the first formal prospective trial using infusion times shorter than the standard schedule directly after an initial 4-hours dose. This rapid infusion protocol has resulted in more efficient resource utilization and has become the standard protocol for the use in all intravenous daratumumab regimens in Canada. This approach has been particularly helpful in shortening chair time during the COVID-19 pandemic and providing a useful alternative in jurisdictions without access to subcutaneous daratumumab.

A Clinical and Correlative Study of Elotuzumab, Carfilzomib, Lenalidomide, and Dexamethasone (Elo-KRd) for Lenalidomide Refractory Multiple Myeloma in First Relapse.

INTRODUCTION: Treatment of patients with multiple myeloma (MM) in first relapse remains a challenge. This phase II study combined elotuzumab (Elo) with carfilzomib, lenalidomide, and dexamethasone (KRd) for treatment of MM in first relapse with the aim of improving efficacy. METHODS: Enrolled patients received Elo-KRd induction for 4 cycles, and Elo-lenalidomide maintenance until progression. The primary endpoint was VGPR or better (≥VGPR) postinduction. Secondary endpoints were MRD by flow cytometry, OS, PFS, and safety. Correlatives included characterization of the impact of Elo-KRd on NK and T cell subsets via flow cytometry. Target accrual of 40 patients was not met due to COVID-19 pandemic. RESULTS: Of 15 patients enrolled, 10 (67%) had high-risk features (del17p, t[4;14], t[14;16], 1q gain/amplification, plasma cell leukemia, extramedullary MM, or functional high risk), 12 (80%) were lenalidomide-refractory, and 5 (33.3%) bortezomib-refractory. Postinduction ≥VGPR was 7/15 (46.7%) and MRD-negative (10-5) rate 20%. Overall response during study was 80%, including ≥VGPR as best response of 53.3%. At median follow-up of 28.2 (range, 3.8 to 44.2) months, the median PFS was 11.5 months (95% CI 1.9, 18), and median OS not reached (95% CI 10.1, NA). No new safety concerns were reported. Elo-KRd treatment did not augment NK cell distribution or activity in blood or bone marrow. Effector CD4+ and CD8+ T cells significantly decreased postinduction, with concomitant acquisition of T central memory phenotype, particularly at a high rate in ≥VGPR group. CONCLUSION: A short course of Elo-KRd induction followed by Elo-lenalidomide maintenance demonstrated activity in predominantly lenalidomide-refractory and / or high-risk MM. The results with this well-tolerated combination are comparable to other contemporary approved triplet combinations.

Response to COVID-19 Vaccination Post-CAR T Therapy in Patients With Non-Hodgkin Lymphoma and Multiple Myeloma.

COVID-19 adversely affects individuals with cancer. Several studies have found that seroconversion rates among patients with hematologic malignancies are suboptimal when compared to patients without cancer. Patients with non-Hodgkin lymphoma (NHL) and multiple myeloma (MM) are immunocompromised due to impaired humoral and cellular immunity in addition to prescribed immunosuppressive therapy. Chimeric antigen receptor T-cell (CAR T) therapy is now widely used for NHL and MM, but little is known about seroconversion rates after COVID-19 vaccination among these populations. We evaluated SARS-CoV-2 spike-binding IgG antibody levels following COVID-19 vaccination among NHL and MM CAR T therapy recipients. Out of 104 CAR T infusions, 19 patients developed known COVID-19 infection post-CAR T. We tested 17 patients that received CAR T for antibody spike titers post COVID-19 vaccination, only 29 % (n = 5) were able to mount a clinically relevant antibody response (>250 IU/mL).

Use of Oral Antivirals Ritonavir-Nirmatrelvir and Molnupiravir in Patients with Multiple Myeloma Is Associated with Low Rates of Severe COVID-19: A Single-Center, Prospective Study.

In patients with multiple myeloma (MM), SARS-CoV-2 infection has been associated with a severe clinical course and high mortality rates due to the concomitant disease- and treatment-related immunosuppression. Specific antiviral treatment involves viral replication control with monoclonal antibodies and antivirals, including molnupiravir and the ritonavir-boosted nirmatrelvir. This prospective study investigated the effect of these two agents on SARS-CoV-2 infection severity and mortality in patients with MM. Patients received either ritonavir-nirmatrelvir or molnupiravir. Baseline demographic and clinical characteristics, as well as levels of neutralizing antibodies (NAbs), were compared. A total of 139 patients was treated with ritonavir-nirmatrelvir while the remaining 30 patients were treated with molnupiravir. In total, 149 patients (88.2%) had a mild infection, 15 (8.9%) had a moderate infection, and five (3%) had severe COVID-19. No differences in the severity of COVID-19-related outcomes were observed between the two antivirals. Patients with severe disease had lower neutralizing antibody levels before the COVID-19 infection compared to patients with mild disease (p = 0.04). Regarding treatment, it was observed that patients receiving belantamab mafodotin had a higher risk of severe COVID-19 (p < 0.001) in the univariate analysis. In conclusion, ritonavir-nirmatrelvir and molnupiravirmay prevent severe disease in MM patients with SARS-CoV-2 infection. This prospective study indicated the comparable effects of the two treatment options, providing an insight for further research in preventing severe COVID-19 in patients with hematologic malignancies.

Risk of infections associated with the use of bispecific antibodies in multiple myeloma: a pooled analysis.

The use of bispecific antibodies (BsAbs) in the treatment of relapsed/refractory multiple myeloma (MM) is showing early promising overall response rates in heavily pretreated patients. Infectious complications related to the use of BsAbs are not well described. We conducted a pooled analysis that included all single-agent BsAbs used in MM with no prior use of different BsAbs. A total of 1185 patients with MM were treated with a BsAb in the studied period (71.6% of the patients treated with an agent targeting B-cell maturation antigen (BCMA). Pooled median follow-up was short at 6.1 months (7.5 vs 5.2 months for BCMA vs non-BCMA BsAbs, respectively). Adverse events of interest included all grade neutropenia in 38.6%, all grade infections in 50% (n = 542/1083), all grade cytokine release syndrome in 59.6% (n = 706/1185), grade III/IV neutropenia in 34.8% (n = 372/1068), grade III/IV infections in 24.5% (n = 272/1110), grade III/IV pneumonia in 10% (n = 52.4/506), and grade III/IV coronavirus disease 2019 in 11.4% (n = 45.4/395) of the patients. Non-BCMA-targeted BsAbs were associated with lower grade III/IV neutropenia (25.3% vs 39.2%) and lower grade III/IV infections (11.9% vs 30%) when compared with BCMA-targeted BsAbs. Hypogammaglobulinemia was reported in 4 studies, with a prevalence of 75.3% (n = 256/340) of the patients, with IV immunoglobulin used in 48% (n = 123/256) of them. Death was reported in 110 patients, of which 28 (25.5%) were reported to be secondary to infections. Certain precautions should be used when using BsAbs to mitigate the risk and/or identify and treat infections promptly.

Ruxolitinib and methylprednisolone for treatment of patients with relapsed/refractory multiple myeloma.

Although Janus kinase (JAK) inhibitors have demonstrated efficacy for treating autoimmune disorders and myeloproliferative neoplasms, their efficacy in treating other types of cancer has not been clearly demonstrated. We evaluated oral ruxolitinib (15 mg twice daily) with oral methylprednisolone (40 mg every other day) for multiple myeloma (MM) patients with progressive disease who had received a proteasome inhibitor, lenalidomide, glucocorticosteroids and three or more prior regimens. All of the planned 29 patients had been enrolled with follow-up until 28 April 2022. Median lines of prior therapy were 6 (range 3-12). Cytogenetics and fluorescent in situ hybridization were evaluable in 28 patients; 9 (32%) and 17 (70%) patients showed high-risk cytogenetics and/or 1q+, respectively. The overall response rate was 31%. The median duration of response was 13.1 (range 2.8-22.0) months. Median progression-free survival rate was 3.4 (range 0.5-24.6) months, Overall, the treatment was well tolerated. The combination of ruxolitinib and methylprednisolone demonstrated significant clinical activity among previously heavily-treated MM patients, and responses were achieved among patients who had high-risk cytogenetics. This is the first clinical study to show activity of JAK inhibitors in combination with steroids for MM patients and expands the potential use of these drugs to those with cancers other than myeloproliferative neoplasms.

Selinexor in Patients from Argentina with Multiple Myeloma Treated with Multiple Prior Therapies: A Case Series.

BACKGROUND Numerous treatment options are available for patients with multiple myeloma (MM). Because of the course of the disease, most patients will experience serial relapse or the MM will become refractory to most of these treatments, leaving patients with few or no treatment options over time. Selinexor, a treatment with a novel mechanism of action, is an oral selective inhibitor of nuclear export (SINE) compound that blocks exportin 1, the major nuclear exporter of tumor suppressor proteins. CASE REPORT In this case series, we report on treatment with the weekly oral administration of selinexor combined with bortezomib and dexamethasone (XVd) in 3 patients from Argentina who were heavily treated (5-7 prior therapies) for MM that relapsed or was refractory to each previous treatment. Two patients had the high-risk cytogenetic abnormality del(17p). All 3 patients experienced efficacy with XVd reaching a best response of partial response or very good partial response. These responses were consistent with those of patients from the BOSTON study who were treated with XVd but were less heavily pretreated (1-3 prior therapies) and had a shorter median time since diagnosis of MM (7 years vs 3.7 years). The 3 patients experienced adverse events (AEs) that included nausea, thrombocytopenia, asthenia, and fatigue, which were similar to the most commonly reported AEs associated with selinexor treatment. CONCLUSIONS With its oral administration, novel mechanism of action, and responses in heavily pretreated patients, selinexor may help to address an important clinical need in the treatment of patients with relapsed/refractory MM.

Pomalidomide Treatment in Relapsed/Refractory Multiple Myeloma Patients-Real-World Data From Hungary.

Pomalidomide is a third generation immunomodulatory drug in the treatment of refractory and relapsed multiple myeloma patients. Our aim was to investigate the efficacy and safety of pomalidomide therapy in a real world setting. Eighty-six Hungarian patients were included, 45 of whom received pomalidomide ± an alkylating agent, while in 38 of them pomalidomide was combined with a proteasome inhibitor. 56 patients (65%) showed any response to the treatment with 18 complete or very good partial remissions and 38 partial remissions. At a median duration of follow-up of 18.6 months, the median progression-free survival (PFS) was 9.03 months, while the median overall survival (OS) was 16.53 months in the whole cohort. Patients with early stage disease (R-ISS 1 and 2) had better survival results than those with stage 3 myeloma (p = 0.002). Neither the number of prior treatment lines, nor lenalidomide refractoriness had a significant impact on PFS. PFS was found similar between the cohort of patients with impaired renal function and the cohort without kidney involvement. During the study, eight mortal infections and two fatal bleeding complications occurred, however, mild hematologic and gastrointestinal toxicities were identified as the most frequent adverse events. The results of our investigations confirm that pomalidomide is an effective treatment option for relapsed/refractory MM, besides, the safety profile is satisfactory in subjects with both normal and impaired renal function.

GPRC5D CAR T cells (OriCAR-017) in patients with relapsed or refractory multiple myeloma (POLARIS): a first-in-human, single-centre, single-arm, phase 1 trial.

BACKGROUND: Chimeric antigen receptor (CAR) T-cell therapy targeting B-cell maturation antigen (BCMA) has shown activity in treating relapsed or refractory multiple myeloma; however, relapse is still common, and new targets are needed. We aimed to assess the activity and safety profile of G protein-coupled receptor class C group 5 member D (GPRC5D)-targeted CAR T cells (OriCAR-017) in patients with relapsed or refractory multiple myeloma. METHODS: POLARIS was a first-in-human, single-centre, single-arm, phase 1 trial of GPRC5D-targeted CAR T cells (OriCAR-017) done at the First Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China. Eligible patients were adults aged 18-75 years with a diagnosis of relapsed or refractory multiple myeloma and an ECOG performance status of 0-2, had GPRC5D expression in bone marrow plasma cells greater than 20% or were positive for GPRC5D by immunohistochemistry, and had received at least three previous lines of treatment including proteasome inhibitors, immunomodulatory drugs, and chemotherapy. Patients were consecutively assigned to receive a single dose of intravenous OriCAR-017 at 1 × 106 CAR T cells per kg, 3 × 106 CAR T cells per kg, or 6 × 106 CAR T cells per kg in the dose-escalation phase. In the expansion phase, patients received the recommended phase 2 dose. Recruitment to the expansion phase terminated early due to the COVID-19 pandemic on May 1, 2022. The primary endpoints were safety, the maximum tolerated dose and the recommended phase 2 dose. Safety and activity analyses included all patients who received OriCAR-017. This trial is registered with ClinicalTrials.gov, NCT05016778. This trial has been completed and is entering long-term follow-up. FINDINGS: Between June 9, 2021, and Feb 28, 2022, we recruited 13 patients for inclusion into the study. One patient was excluded because of GPRC5D negativity and two patients discontinued after apheresis because of rapid progression. Nine patients were assigned to the dose escalation phase (three received 1 × 106 CAR T cells per kg, three received 3 × 106 CAR T cells per kg, and three received 6 × 106 CAR T cells per kg). The maximum tolerated dose was not identified, because no dose-limiting toxic effects were observed. On the basis of safety and preliminary activity, the recommended phase 2 dose was set at 3 × 106 CAR T cells per kg, which was received by one additional patient in the dose expansion phase. Five patients (50%) were female, five (50%) were male, and all were Chinese. Five patients (50%) were previously treated with BCMA-targeted CAR T-cell therapy. Median follow-up was 238 days (IQR 182-307). There were no serious adverse events and no treatment-related deaths. The most common grade 3 or worse adverse events were haematological, including neutropenia (ten [100%] of ten patients), thrombocytopenia (nine [90%]), leukopenia (nine [90%]), and anaemia (seven [70%]). All patients had cytokine release syndrome (nine [90%] grade 1 and one [10%] grade 2). No neurological toxic effects were reported. Ten (100%) of ten patients had an overall response, of whom six (60%) had a stringent complete response and four (40%) had very good partial response. Two patients discontinued due to disease progression (one GPRC5D-positive patient in the middle-dose group and one GPRC5D-negative patient in the low-dose group). INTERPRETATION: The results of this study suggest that GPRC5D is an active target for immunotherapy in multiple myeloma. GPRC5D-targeted CAR T-cell therapy is a promising treatment modality for patients with relapsed or refractory multiple myeloma and deserves further testing. FUNDING: OriCell Therapeutics.

Oral antivirals against Sars-CoV-2 in multiple myeloma outpatients: a case series.

Recently, the therapeutic armamentarium against Sars-CoV-2 has been enriched with oral antivirals that can be used in the early phases of covid-19. Real-life data on their efficacy in multiple myeloma (Mm) outpatients with mild-to-moderate covid-19 are lacking. We described the clinical outcomes at 30 days in Mm subjects with covid-19 treated with oral antivirals. Nirmatrelvir/r was prescribed in 10 subjects whereas molnupiravir in 5. Despite two hospitalizations were reported, we did not observe deaths due to covid-19 in this vulnerable group. Our preliminary observations reinforce the early use of oral antivirals as a useful means to contain severe covid-19 in high-risk patients such as Mm individuals characterized by an impaired immune response.

Kinetics of Humoral Immunodeficiency With Bispecific Antibody Therapy in Relapsed Refractory Multiple Myeloma.

This case series describes the kinetics of humoral deficiency in patients with relapsed refractory multiple myeloma treated with bispecific antibodies, the infectious complications, and response to COVID-19 immunization.

Herpesviral encephalitis associated with bortezomib use in a patient with multiple myeloma and associated light-chain amyloidosis.

INTRODUCTION: Bortezomib is proteasome inhibitor used in multiple myeloma treatment. The reactivation of herpes simplex virus (HSV) and varicella-zoster virus (VZV) during bortezomib-based therapy is a well-known adverse event. Antiviral prophylaxis is mandatory. Nevertheless, reports of herpesviral encephalitis are scarce. CASE REPORT: A 57-year-old multiple myeloma patient who during CyBorD protocol (Bortezomib, cyclophosphamide, and dexamethasone), after a transient suspension of antiviral prophylaxis presented progressive headaches unresponsive to conventional analgesics, asthenia, fever, episodic visual hallucinations, and vesicular lesions in the right supraorbital and frontal region. Herpetic encephalitis was diagnosed after detecting herpes zoster in cerebrospinal fluid. MANAGEMENT & OUTCOME: The patient was treated with acyclovir 500mg every 6 hours for 21 days, and subsequent valacyclovir prophylaxis achieving an excellent clinical evolution. Anti-myeloma treatment was changed to lenalidomide and dexamethasone achieving a durable complete response. Herpesviral encephalitis is a rare but severe complication associated with the use of Bortezomib, especially when patients did not receive acyclovir prophylaxis. However, a rapid detection based on the clinical suspicion, and the prompt start of treatment, may lead to overcome this adverse event.

Teclistamab in Relapsed or Refractory Multiple Myeloma.

BACKGROUND: Teclistamab is a T-cell-redirecting bispecific antibody that targets both CD3 expressed on the surface of T cells and B-cell maturation antigen expressed on the surface of myeloma cells. In the phase 1 dose-defining portion of the study, teclistamab showed promising efficacy in patients with relapsed or refractory multiple myeloma. METHODS: In this phase 1-2 study, we enrolled patients who had relapsed or refractory myeloma after at least three therapy lines, including triple-class exposure to an immunomodulatory drug, a proteasome inhibitor, and an anti-CD38 antibody. Patients received a weekly subcutaneous injection of teclistamab (at a dose of 1.5 mg per kilogram of body weight) after receiving step-up doses of 0.06 mg and 0.3 mg per kilogram. The primary end point was the overall response (partial response or better). RESULTS: Among 165 patients who received teclistamab, 77.6% had triple-class refractory disease (median, five previous therapy lines). With a median follow-up of 14.1 months, the overall response rate was 63.0%, with 65 patients (39.4%) having a complete response or better. A total of 44 patients (26.7%) were found to have no minimal residual disease (MRD); the MRD-negativity rate among the patients with a complete response or better was 46%. The median duration of response was 18.4 months (95% confidence interval [CI], 14.9 to not estimable). The median duration of progression-free survival was 11.3 months (95% CI, 8.8 to 17.1). Common adverse events included cytokine release syndrome (in 72.1% of the patients; grade 3, 0.6%; no grade 4), neutropenia (in 70.9%; grade 3 or 4, 64.2%), anemia (in 52.1%; grade 3 or 4, 37.0%), and thrombocytopenia (in 40.0%; grade 3 or 4, 21.2%). Infections were frequent (in 76.4%; grade 3 or 4, 44.8%). Neurotoxic events occurred in 24 patients (14.5%), including immune effector cell-associated neurotoxicity syndrome in 5 patients (3.0%; all grade 1 or 2). CONCLUSIONS: Teclistamab resulted in a high rate of deep and durable response in patients with triple-class-exposed relapsed or refractory multiple myeloma. Cytopenias and infections were common; toxic effects that were consistent with T-cell redirection were mostly grade 1 or 2. (Funded by Janssen Research and Development; MajesTEC-1 ClinicalTrials.gov numbers, NCT03145181 and NCT04557098.).

Bendamustine in combination with pomalidomide and dexamethasone in relapsed/refractory multiple myeloma: A phase II trial.

Treatment of patients with resistant/refractory multiple myeloma (MM) is an unmet need. In this phase II study, we evaluated the role of bendamustine, pomalidomide and dexamethasone combination in this setting. Between February 2020 and December 2021, 28 patients were recruited. Patients received bendamustine 120 mg/m2 day 1, pomalidomide 3 mg days 1-21, and dexamethasone 40 mg days 1, 8, 11, 22, regimen given for a maximum of six cycles. The median (range) age of the patients was 54 (30-76) years and 15 (53.6%) were males. Patients had received a median (range) of three (two-six) prior lines and 85.7% were refractory to both lenalidomide and bortezomib. The primary end-point was the overall response rate (ORR) defined as ≥partial response after at least three cycles. Secondary objectives were toxicity, progression-free survival (PFS), time to progression and overall survival (OS). An intent-to-treat analysis was done. An ORR of 57.6% was achieved. Patients with extramedullary myeloma had a better response rate. At a median follow-up of 8.6 months, the median PFS and OS were 6.2 and 9.7 months respectively. Toxicity was manageable; mainly haematological (neutropenia, 46.4%; anaemia, 42.8%; and thrombocytopenia, 7.1%). Bendamustine, pomalidomide and dexamethasone could be a novel combination for the heavily pretreated, lenalidomide-refractory myeloma population.

Infections in relapsed myeloma patients treated with isatuximab plus pomalidomide and dexamethasone during the COVID-19 pandemic: Initial results of a UK-wide real-world study.

OBJECTIVES: There are no real-world data describing infection morbidity in relapsed/refractory myeloma (RRMM) patients treated with anti-CD38 isatuximab in combination with pomalidomide and dexamethasone (IsaPomDex). In this UK-wide retrospective study, we set out to evaluate infections experienced by routine care patients who received this novel therapy across 24 cancer centres during the COVID-19 pandemic. METHODS: The primary endpoint was infection morbidity (incidence, grading, hospitalization) as well as infection-related deaths. Secondary outcomes were clinical predictors of increased incidence of any grade (G2-5) and high grade (≥G3) infections. RESULTS: In a total cohort of 107 patients who received a median (IQR) of 4 cycles (2-8), 23.4% of patients experienced ≥1 any grade (G2-5) infections (total of 31 episodes) and 18.7% of patients experienced ≥1 high grade (≥G3) infections (total of 22 episodes). Median time (IQR) from start of therapy to first episode was 29 days (16-75). Six patients experienced COVID-19 infection, of whom 5 were not vaccinated and 1 was fully vaccinated. The cumulative duration of infection-related hospitalizations was 159 days. The multivariate (MVA) Poisson Regression analysis demonstrated that a higher co-morbidity burden with Charlson Co-morbidity Index (CCI) score ≥4 (incidence rate ratio (IRR) = 3, p = 0.012) and sub-optimal myeloma response less than a partial response (

The impact of COVID-19 on autologous stem cell transplantation in multiple myeloma: A single-centre, qualitative evaluation study.

Autologous stem cell transplantation (ASCT) is standard of care in biologically fit, newly diagnosed multiple myeloma (MM) patients, offering better therapeutic outcomes and improved quality of life (QoL). However, with the UK's 1st national lockdown on 23/03/2020, several guidelines recommended deferring ASCT due to risks of infection, with resource limitations forcing some units to suspend ASCT entirely. Such changes to patients' treatment plans inevitably altered their lived experience during these uncertain times with expected impact on QoL. We conducted a qualitative study using semi-structured interviews to gain insight into MM patients' understanding of their disease, initial therapy and ASCT, and their response to therapy changes. A clinical snapshot of how COVID-19 affected the MM ASCT service in a single UK institution is also provided, including changes to chemotherapy treatment plans, timing, and prioritisation of ASCT. Framework analysis identified 6 overarching themes: (1) beliefs about ASCT, (2) perceptions of information provided about MM and ASCT, (3) high levels of fear and anxiety due to COVID-19, (4) feelings about ASCT disruption or delay due to COVID-19, (5) perceptions of care, and (6) importance of social support. Example subthemes were beliefs that ASCT would provide a long-remission/best chance of normality including freedom from chemotherapy and associated side-effects, disappointment, and devastation at COVID-related treatment delays (despite high anxiety about infection) and exceptionally high levels of trust in the transplant team. Such insights will help us adjust our service and counselling approaches to be more in tune with patients' priorities and expectations.

A case of Bacillus subtilis var. natto bacteremia caused by ingestion of natto during COVID-19 treatment in a maintenance hemodialysis patient with multiple myeloma.

A 70-year-old woman, who started on hemodialysis 7 months before for end-stage renal disease due to diabetic nephropathy and was diagnosed with symptomatic multiple myeloma 1 month before, was admitted to our hospital with critical coronavirus disease 2019 and treated with long-term immunosuppressive therapy such as steroids and tocilizumab. During treatment, Bacillus subtilis was detected in the blood cultures. We could not exclude the association of natto (fermented soybeans) with B. subtilis var. natto, which the patient had been eating every day from 8 days after admission. She was prohibited from eating natto and treated with vancomycin. Later, B. subtilis detected in the blood culture was identified as B. subtilis var. natto, which was identical with those contained in the natto that the patient consumed daily using a next-generation sequencer. Gut dysbiosis due to old age, malignant tumor, diabetes mellitus, end-stage renal disease, and intestinal inflammation caused by severe acute respiratory syndrome coronavirus 2 increased intestinal permeability and the risk of bacterial translocation, causing B. subtilis var. natto bacteremia. Therefore, careful consideration might be given to the intake of fermented foods containing live bacteria in patients with severe immunocompromised conditions.