Absolute lymphocyte count after BCMA CAR-T therapy is a predictor of response and outcomes in relapsed multiple myeloma.

ABSTRACT: B-cell maturation antigen (BCMA)-targeting chimeric antigen receptor T cells (CAR-Ts) used in multiple myeloma (MM) are rapidly becoming a mainstay in the treatment of relapsed/refractory (R/R) disease, and CAR-T expansion after infusion has been shown to inform depth and duration of response (DoR), but measuring this process remains investigational. This multicenter study describes the kinetics and prognostic impact of absolute lymphocyte count (ALC) in the first 15 days after CAR-T infusion in 156 patients with relapsed MM treated with the BCMA-targeting agents ciltacabtagene autoleucel and idecabtagene vicleucel. Patients with higher maximum ALC (ALCmax) had better depth of response, progression-free survival (PFS), and DoR. Patients with ALCmax >1.0 × 103/µL had a superior PFS (30.5 months vs 6 months; P < .001) compared with those with ≤1.0 × 103/µL, whereas patients with ALCmax ≤0.5 × 103/µL represent a high-risk group with early disease progression and short PFS (hazard ratio, 3.4; 95% confidence interval, 2-5.8; P < .001). In multivariate analysis, ALCmax >1.0 × 103/µL and nonparaskeletal extramedullary disease were the only independent predictors of PFS and DoR after accounting for international staging systemic staging, age, CAR-T product, high-risk cytogenetics, and the number of previous lines. Moreover, our flow cytometry data suggest that ALC is a surrogate for BCMA CAR-T expansion and can be used as an accessible prognostic marker. We report, to our knowledge, for the first time the association of ALC after BCMA CAR-T infusion with clinical outcomes and its utility in predicting response in patients with R/R MM.

Improved serologic responses to DTaP over Tdap vaccination in adult hematopoietic cell transplant recipients.

BACKGROUND: Hematopoietic cell transplantation (HCT) recipients have reduced antibody titers to tetanus, diphtheria, and pertussis. Tdap is approved for revaccinating adult HCT recipients in the United States, whereas DTaP is not approved in this population. To our knowledge, no studies to date have compared responses to DTaP versus Tdap in adult HCT patients. We conducted a retrospective study comparing responses to DTaP versus Tdap vaccines in otherwise similar adult HCT patients in order to determine if one of these vaccines elicits superior antibody responses. METHODS: We evaluated 43 allogeneic and autologous transplant recipients as a combined cohort and as separate subsets for vaccine specific antibody titers and proportion of strong vaccine responders. Subset analysis focused on the autologous transplant recipients. RESULTS: Higher median antibody titers were found to all vaccine components among DTaP recipients (diphtheria p = .021, pertussis p = .020, tetanus p = .007). DTaP recipients also had more strong responders to diphtheria and pertussis (diphtheria p = .002, pertussis p = .006). Among the autologous HCT recipient subset, there were more strong responders to diphtheria (p = .036). CONCLUSIONS: Our data shows that post-HCT vaccination with DTaP leads to higher antibody titers and more strong responders, which suggests that DTaP is more effective than Tdap in HCT recipients.

Antibiotic Exposure, Not Alloreactivity, Is the Major Driver of Microbiome Changes in Hematopoietic Cell Transplantation.

Both autologous hematopoietic cell transplantation (auto-HCT) and allogeneic hematopoietic cell transplantation (allo-HCT) are associated with significant alterations in the intestinal microbiome. The relative contributions of antibiotic use and alloreactivity to microbiome dynamics have not yet been elucidated, however. There is a lack of data on the kinetics of microbiome changes beyond 30 days post-transplantation and how they might differ between different transplantation modalities. A direct comparison of the differential effects of auto-HCT and allo-HCT on the microbiome may shed light on these dynamics. This study was conducted to compare intestinal microbial diversity between auto-HCT recipients and allo-HCT recipients from pre-transplantation to 100 days post-transplantation, and to examine the effect of antibiotics, transplant type (auto versus allo), and conditioning regimens on the dynamics of microbiome recovery. We conducted a longitudinal analysis of changes in the intestinal microbiome in 35 patients undergoing HCT (17 auto-HCT, 18 allo-HCT) at 4 time points: pre-conditioning and 14, 28, and 100 days post-transplantation. Granular data on antibiotic exposure from day -30 pre-transplantation to day +100 post-transplantation were collected. Pre-transplantation, allo-HCT recipients had lower α-diversity in the intestinal microbiome compared with auto-HCT recipients, which correlated with greater pre-transplantation antibiotic use in allo-HCT recipients. The microbiome diversity declined at days +14 and +28 post-transplantation in both cohorts but generally returned to baseline by day +100. Conditioning regimen intensity did not significantly affect post-transplantation α-diversity. Through differential abundance analysis, we show that commensal bacterial taxa involved with maintenance of gut epithelial integrity and production of short-chain fatty acids were depleted after both auto-HCT and allo-HCT. In our dataset, antibiotic exposure was the major driver of post-transplantation microbiome changes rather than alloreactivity, conditioning intensity, or immunosuppression. Our findings also suggest that interventions to limit microbiome injury, such as limiting the use of broad-spectrum antibiotics, should target the pre-transplantation period and not only the peri-transplantation period.

What about tocilizumab? A retrospective study from a NYC Hospital during the COVID-19 outbreak.

BACKGROUND: Tocilizumab, an interleukin-6 receptor blocker, has been used in the inflammatory phase of COVID-19, but its impact independent of corticosteroids remains unclear in patients with severe disease. METHODS: In this retrospective analysis of patients with COVID-19 admitted between March 2 and April 14, 2020 to a large academic medical center in New York City, we describe outcomes associated with tocilizumab 400 mg (without methylprednisolone) compared to a propensity-matched control. The primary endpoints were change in a 7-point ordinal scale of oxygenation and ventilator free survival, both at days 14 and 28. Secondary endpoints include incidence of bacterial superinfections and gastrointestinal perforation. Primary outcomes were evaluated using t-test. RESULTS: We identified 33 patients who received tocilizumab and matched 74 controls based on demographics and health measures upon admission. After adjusting for illness severity and baseline ordinal scale, we failed to find evidence of an improvement in hypoxemia based on an ordinal scale at hospital day 14 in the tocilizumab group (OR 2.2; 95% CI, 0.7-6.5; p = 0.157) or day 28 (OR 1.1; 95% CI, 0.4-3.6; p = 0.82). There also was no evidence of an improvement in ventilator-free survival at day 14 (OR 0.8; 95% CI, 0.18-3.5; p = 0.75) or day 28 (OR 1.1; 95% CI, 0.1-1.8; p = 0.23). There was no increase in secondary bacterial infection rates in the tocilizumab group compared to controls (OR 0.37; 95% CI, 0.09-1.53; p = 0.168). CONCLUSIONS: There was no evidence to support an improvement in hypoxemia or ventilator-free survival with use of tocilizumab 400 mg in the absence of corticosteroids. No increase in secondary bacterial infections was observed in the group receiving tocilizumab.

Gastrointestinal toxicity of high-dose melphalan in autologous hematopoietic stem cell transplantation: identification of risk factors and a benchmark for experimental therapies.

Gastrointestinal side effects are the dose-limiting toxicity of high-dose melphalan (HDM) in autologous hematopoietic stem-cell transplantation, but there are limited contemporary data on the incidence and severity of gastrointestinal toxicity associated with this regimen. We retrospectively studied 100 consecutive patients who received HDM alone or in combination with other conditioning agents. Patients had a median age of 56 (range 20-73); underlying diseases were myeloma (42%), lymphoma (42%), or amyloidosis (16%) and melphalan dosages were 200 (40%), 140 (59%), or 100 mg/m2 (1%). Ninety-seven percent of patients experienced diarrhea with a range of 1-18 bowel movements per day, 88% developed nausea, and 60% experienced vomiting. Abdominal CT scans rarely altered patient management, but stool studies were useful in identifying a treatable infectious source. Grade ≥ 2 diarrhea was associated with longer duration of diarrhea, longer length of stay, worse hypoalbuminemia, higher use of antibiotics, abdominal imaging, electrolyte repletions, and anti-diarrheal agents. Risk factors for severe diarrhea were female sex, melphalan dose, age > 50, creatinine clearance < 60 ml/min, and having a plasma cell neoplasm as opposed to lymphoma. Female sex was also associated with more severe nausea and vomiting. In summary, diarrhea remains an important toxicity of HDM and novel therapies for chemotherapy-induced diarrhea for patients undergoing stem-cell transplantation are needed. Grade 2 or higher diarrhea is associated with significant clinical consequences and should be used as the primary endpoint in prospective clinical trials.

Extended letermovir administration, beyond day 100, is effective for CMV prophylaxis in patients with graft versus host disease.

BACKGROUND: Cytomegalovirus (CMV) reactivation is associated with significant morbidity and mortality after an allogeneic hematopoietic cell transplant (AHCT), and graft versus host disease (GVHD) increases the risk of CMV reactivation. Letermovir is approved for CMV prophylaxis in CMV-seropositive patients, but has only been studied through day 100 post-transplantation in the registration trial. Its efficacy in preventing CMV in patients with GVHD requiring treatment beyond the day 100 milestone has not been studied. METHODS: We retrospectively analyzed all patients who underwent an AHCT at a single center over a period of 24 months, and identified a cohort of 20 patients who received extended duration of letermovir (beyond 100 days) after the diagnosis of GVHD. The primary end point was the incidence of clinically significant CMV infection, defined as onset of CMV disease or initiation of preemptive therapy with alternative antiviral agents. RESULTS: In this high-risk cohort, only one patient (5%) developed a clinically significant CMV infection, requiring preemptive therapy. No patients developed CMV organ disease. Three additional patients developed CMV viremia of ≥150 IU/mL while on letermovir and after the onset of GVHD, and none required additional treatment. Receipt of post-transplant cyclophosphamide (PTCy) and low CD4 count after the development of GVHD were associated with breakthrough CMV viremia while on extended duration letermovir. CONCLUSIONS: Extended duration letermovir was efficacious in preventing clinically significant CMV infections in patients with GVHD.

COVID-19 infections and outcomes in patients with multiple myeloma in New York City: a cohort study from five academic centers.

Importance: New York City is a global epicenter for the SARS-CoV-2 outbreak with a significant number of individuals infected by the virus. Patients with multiple myeloma have a compromised immune system, due to both the disease and anti-myeloma therapies, and may therefore be particularly susceptible to coronavirus disease 2019 (COVID-19); however, there is limited information to guide clinical management. Objective: To assess risk factors and outcomes of COVID-19 in patients with multiple myeloma. Design: Case-series. Setting: Five large academic centers in New York City. Participants: Patients with multiple myeloma and related plasma cell disorders who were diagnosed with COVID-19 between March 10th, 2020 and April 30th, 2020. Exposures: Clinical features and risk factors were analyzed in relation to severity of COVID-19. Main Outcomes and Measures: Descriptive statistics as well as logistic regression were used to estimate disease severity reflected in hospital admissions, intensive care unit (ICU) admission, need for mechanical ventilation, or death. Results: Of 100 multiple myeloma patients (male 58%; median age 68, range 41-91) diagnosed with COVID-19, 74 (74%) were admitted; of these 13 (18%) patients were placed on mechanical ventilation, and 18 patients (24%) expired. None of the studied risk factors were significantly associated (P>0.05) with adverse outcomes (ICU-admission, mechanical ventilation, or death): hypertension (N=56) odds ratio (OR) 2.3 (95% confidence interval [CI] 0.9-5.9); diabetes (N=18) OR 1.1 (95% CI 0.3-3.2); age >65 years (N=63) OR 2.0 (95% CI 0.8-5.3); high dose melphalan with autologous stem cell transplant <12 months (N=7) OR 1.2 (95% CI 0.2-7.4), IgG<650 mg/dL (N=42) OR=1.2 (95% CI 0.4-3.1). In the entire series of 127 patients with plasma cell disorders, hypertension was significantly associated with the combined end-point (OR 3.4, 95% CI 1.5-8.1). Conclusions and Relevance: Although multiple myeloma patients have a compromised immune system due to both the disease and therapy; in this largest disease specific cohort to date of patients with multiple myeloma and COVID-19, compared to the general population, we found risk factors for adverse outcome to be shared and mortality rates to be within the higher range of officially reported mortality rates.

COVID-19 Infections and Clinical Outcomes in Patients with Multiple Myeloma in New York City: A Cohort Study from Five Academic Centers.

Patients with multiple myeloma have a compromised immune system, due to both the disease and antimyeloma therapies, and may therefore be particularly susceptible to COVID-19. Here, we report outcomes and risk factors for serious disease in patients with multiple myeloma treated at five large academic centers in New York City in the spring of 2020, during which it was a global epicenter of the SARS-CoV-2 pandemic. Of 100 patients with multiple myeloma (male 58%; median age 68) diagnosed with COVID-19, 75 were admitted; of these, 13 patients (17%) were placed on invasive mechanical ventilation, and 22 patients (29%) expired. Of the 25 nonadmitted patients, 4 were asymptomatic. There was a higher risk of adverse outcome (intensive care unit admission, mechanical ventilation, or death) in Hispanics/Latinos (n = 21), OR = 4.7 (95% confidence interval, 1.3-16.7), and African American Blacks (n = 33), OR = 3.5 (1.1-11.5), as compared with White patients (n = 36). Patients who met the adverse combined endpoint had overall higher levels of inflammatory markers and cytokine activation. None of the other studied risk factors were significantly associated (P > 0.05) with adverse outcome: hypertension (n = 56), OR = 2.2 (0.9-5.4); diabetes (n = 18), OR = 0.9 (0.3-2.9); age >65 years (n = 63), OR = 1.8 (0.7-4.6); high-dose melphalan with autologous stem cell transplant <12 months (n = 7), OR = 0.9 (0.2-5.4); and immunoglobulin G <650 mg/dL (n = 42), OR = 0.9 (0.3-2.2). In this largest cohort to date of patients with multiple myeloma and COVID-19, we found the case fatality rate to be 29% among hospitalized patients and that race/ethnicity was the most significant risk factor for adverse outcome. Significance: Patients with multiple myeloma are immunocompromised, raising the question whether they are at higher risk of severe COVID-19 disease. In this large case series on COVID-19 in patients with multiple myeloma, we report 29% mortality rates among hospitalized patients and identify race/ethnicity as the most significant risk factor for severe outcome.See related commentary by Munshi and Anderson, p. 218. This article is highlighted in the In This Issue feature, p. 215.

Correction: COVID-19 Infections and Outcomes in Patients with Multiple Myeloma in New York City: A Cohort Study from Five Academic Centers.

[This corrects the article DOI: 10.1158/2643-3230.BCD-20-0102.].