Infusion reactions in natural killer cell immunotherapy: a retrospective review.

BACKGROUND AIMS: The use of natural killer (NK) cells as a cellular immunotherapy has increased over the past decade, specifically in patients with hematologic malignancies. NK cells have been used at the authors' institution for over 15 years. Most patients have a reaction to NK cell infusion. The authors retrospectively analyzed the reactions associated with NK cell infusions to characterize the types of reactions and investigate why some patients have higher-grade reactions than others. METHODS: A retrospective chart review of NK cell infusions was performed at the authors' institution under nine clinical protocols from 2008 to 2016. An infusion reaction was defined as any symptom from the time of NK cell infusion up to 4 h after infusion completion. The severity of infusion reactions was graded based on Common Terminology Criteria for Adverse Events, version 4. Two major endpoints of interest were (i) infusion reaction with any symptom and (ii) grade ≥3 infusion reaction. Multivariable logistic regression models were used to investigate the association between variables of interest and outcomes. Odds ratios (ORs) and 95% confidence intervals (CIs) were obtained for each variable. RESULTS: A total of 130 patients were receiving NK cell infusions at the authors' institution. The most common reported symptom was chills (n = 110, 85%), which were mostly grade 1 and 2, with only half of patients requiring intervention. There were 118 (91%) patients with infusion reactions, and only 36 (28%) were grade 3. There was one life-threatening grade 4 reaction, and no death was reported due to infusion reaction. Among grade ≥3 reactions, cardiovascular reactions (mainly hypertension) were the most common, and less than half of those with hypertension required intervention. NK cell dose was not associated with any of the grade 3 infusion reactions, whereas monocyte dose was associated with headache (grade ≤3, OR, 2.17, 95% CI, 1.19-3.97) and cardiovascular reaction (grade ≥3, OR, 2.13, 95% CI, 1.13-3.99). Cardiovascular reaction (grade ≥3) was also associated with in vitro IL-2 incubation and storage time. Additionally, there was no association between grade ≥3 infusion reactions and overall response rate (OR, 0.75, 95% CI, 0.29-1.95). CONCLUSIONS: The majority of patients who receive NK cell therapy experience grade 1 or 2 infusion reactions. Some patients experience grade 3 reactions, which are mainly cardiovascular, suggesting that close monitoring within the first 4 h is beneficial. The association of monocytes with NK cell infusion reaction relates to toxicities seen in adoptive T-cell therapy and needs further exploration.

Comparison of continuous versus intermittent infusion cyclosporine and impact on transplant related outcomes in allogeneic transplant recipients.

INTRODUCTION: Continuous infusion (CIVI) cyclosporine (CsA) is an alternative for allograft recipients intolerant of twice daily infusions (TDI). The importance of achieving therapeutic levels of CsA early after allogeneic HCT has been demonstrated in previous studies. Our study evaluated the incidence of acute graft versus host disease (GVHD) and survival among patients receiving CIVI vs. TDI CsA during their first allogeneic HCT. METHODS: A retrospective study of adult patients undergoing first allogeneic HCT at the University of Minnesota Medical Center between 2011 and 2017. Patients were grouped according to the administration method. The primary outcome was the occurrence of acute grade II-IV GVHD by day +180. Secondary outcomes included the 1-year incidence of chronic GVHD, relapse, and overall survival. RESULTS: 42 patients intolerant of TDI CsA received CsA via CIVI for >48 hours for a median of 9 days (range, 3-32 days). CsA concentrations were similar between groups. We found no difference between the rates of grade II-IV acute (45% vs 53%, p = 0.59) or chronic (17% vs 30%, p = 0.20) GVHD or overall survival (57% vs 67%, p = 0.10). Subgroup analysis of patients that received myeloablative conditioning or umbilical cord blood did not reveal significant differences in GVHD or overall survival. Cumulative incidence of relapse was higher among the continuous infusion group (39% vs. 23%, p < 0.01). CONCLUSION: Due to the finding of increased risk of relapse, cyclosporine should be administered as traditional twice daily infusion unless necessary. A prospective clinical trial is needed to confirm these results.

Use of Potentially Inappropriate Medications in Older Allogeneic Hematopoietic Cell Transplantation Recipients.

The use of potentially inappropriate medications (PIMs) using Beers criteria and its impact on older allogeneic hematopoietic cell transplantation (HCT) recipients is not known. Here the use of any PIMs and their therapeutic classes in reduced-intensity conditioning allogeneic HCT recipients were compared between older (≥65 years; n = 114) and younger (40 to 64 years; n = 240) patients during their initial HCT admission, defined as the number of days that a patient received 1 or more PIMs between day -14 and day +28. Poisson regression was used to determine rate ratios (RRs) in the 2 groups. In the ≥65 years group, we evaluated the impact of PIMs on Common Terminology Criteria for Adverse Events (CTCAE) grade 3-4 toxicities within 100 days and on overall mortality within 1 year post-HCT. The rate of any PIM use was similar in the older and younger groups (RR, .98; 95% confidence interval [CI], .90 to 1.06; P = .65). In terms of PIM classes, the older group had a 48% higher rate of gastrointestinal (GI) medication use (RR, 1.48; 95% CI, 1.32 to 1.65; P < .01) and a 25% higher rate of genitourinary (GU) medication use (RR, 1.25; 95% CI, 1.02 to 1.53; P = .03). Compared with males, females had a 19% higher rate of central nervous system (CNS) medication use (RR, 1.19; 95% CI, 1.03 to 1.37; P = .02) and a 30% higher rate of benzodiazepine use (RR, 1.30; 95% CI. 1.09 to 1.54; P < .01). A high-risk HCT-CI was associated with a higher rate of use of any PIMs (RR, 1.13; 95% CI, 1.01 to 1.26; P = .02), CNS medications (RR, 1.26; 95% CI, 1.04 to 1.53; P = .02) and GU medications (RR, 1.46; 95% CI, 1.09 to 1.94; P = .01). Compared with matched sibling donor HCT recipients, umbilical cord blood transplantation recipients had higher rates of GI medication use (RR, 1.32; 95% CI, 1.14 to 1.53; P < .01) and anticholinergic medication use (RR, 1.30; 95% CI, 1.06 to 1.61; P = .01). In the ≥65 years group, increasing duration of narcotic use was associated with a 1.3-fold (95% CI, 1.0 to 1.7; P = .05) higher risk of overall mortality and a 1.6-fold (95% CI, 1.02 to 2.69) greater odds of CTCAE grade 3-4 toxicities (P = .04). Our data show that older recipients (≥65 years) were as likely as their younger counterparts to receive PIMs. Among older recipients, the use of PIMs, particularly narcotics, was associated with higher mortality and higher incidence of grade 3-4 toxicities. Identifying and reducing the use of PIMs in older HCT recipients may help decrease the burden of adverse events and associated health care costs.

Follistatin and Soluble Endoglin Predict 1-Year Nonrelapse Mortality after Allogeneic Hematopoietic Cell Transplantation.

Damage-associated angiogenic factors (AFs), including follistatin (FS) and soluble endoglin (sEng), are elevated in circulation at the onset of acute graft-versus-host disease (GVHD). We hypothesized that regimen-related tissue injury also might be associated with aberrant AF levels and sought to determine the relevance of these AF on nonrelapse mortality (NRM) in patients with acute GVHD and those without acute GVHD. To test our hypothesis, we analyzed circulating levels of FS, sEng, angiopoietin-2 (Ang2), epidermal growth factor (EGF), vascular endothelial growth factor (VEGF) A and B, placental growth factor (PlGF), and soluble VEGF receptor (sVEGFR)-1 and -2, in plasma samples from patients enrolled on Blood and Marrow Transplant Clinical Trials Network (BMT CTN) 0402 (n = 221), which tested GVHD prophylaxis after myeloablative hematopoietic stem cell transplantation (HCT). We found that the interaction between FS and sEng had an additive effect in their association with 1-year NRM. In multivariate analysis, patients with the highest levels of day +28 FS and sEng had a 14.9-fold greater hazard ratio (HR) of NRM (95% confidence interval, 3.2 to 69.4; P < .01) when compared with low levels of FS and sEng. We validated these findings using an external cohort of patients (n = 106). Pre-HCT measurements of FS and sEng were not associated with NRM, suggesting that elevations in these factors early post-HCT may be consequences of early regimen-related toxicity. Determining the mechanisms responsible for patient-specific vulnerability to treatment toxicities and endothelial damage associated with specific AF elevation may guide interventions to reduce NRM post-HCT.

First-in-human phase 1 clinical study of the IL-15 superagonist complex ALT-803 to treat relapse after transplantation.

New therapies for patients with hematologic malignancies who relapse after allogeneic hematopoietic cell transplantation (allo-HCT) are needed. Interleukin 15 (IL-15) is a cytokine that stimulates CD8+ T-cell and natural killer (NK) cell antitumor responses, and we hypothesized this cytokine may augment antileukemia/antilymphoma immunity in vivo. To test this, we performed a first-in-human multicenter phase 1 trial of the IL-15 superagonist complex ALT-803 in patients who relapsed >60 days after allo-HCT. ALT-803 was administered to 33 patients via the IV or subcutaneous (SQ) routes once weekly for 4 doses (dose levels of 1, 3, 6, and 10 µg/kg). ALT-803 was well tolerated, and no dose-limiting toxicities or treatment-emergent graft-versus-host disease requiring systemic therapy was observed in this clinical setting. Adverse events following IV administration included constitutional symptoms temporally related to increased serum IL-6 and interferon-γ. To mitigate these effects, the SQ route was tested. SQ delivery resulted in self-limited injection site rashes infiltrated with lymphocytes without acute constitutional symptoms. Pharmacokinetic analysis revealed prolonged (>96 hour) serum concentrations following SQ, but not IV, injection. ALT-803 stimulated the activation, proliferation, and expansion of NK cells and CD8+ T cells without increasing regulatory T cells. Responses were observed in 19% of evaluable patients, including 1 complete remission lasting 7 months. Thus, ALT-803 is a safe, well-tolerated agent that significantly increased NK and CD8+ T cell numbers and function. This immunostimulatory IL-15 superagonist warrants further investigation to augment antitumor immunity alone and combined with other immunotherapies. This trial was registered at www.clinicaltrials.gov as #NCT01885897.

Validation of Minnesota acute graft-versus-host disease Risk Score.

Using multicenter data, we developed a novel acute graft-versus-host disease Risk Score which more accurately predicts response to steroid treatment, survival and transplant related mortality than other published risk scores based upon clinical grading criteria.1 To validate this Risk Score in a contemporary cohort, we examined 355 recent University of Minnesota patients (2007-2016) diagnosed with acute graft-versus-host disease and treated with prednisone 60 mg/m2/day for 14 days, followed by an 8-week taper. Overall response [complete response + partial response] was higher in the 276 standard risk versus 79 high risk graft-versus-host disease patients at day 14 (71% versus 56%, P<0.01), day 28 (74% versus 59%, P=0.02) and day 56 (68% versus 49%, P<0.01) after steroid initiation. Day 28 response did not differ by the initial graft-versus-host disease grade. In multiple regression analysis, patients with high risk graft-versus-host disease were less likely to respond at day 28 (odds ratio 0.5, 95% CI 0.3-0.9, P<0.01) and had higher risks of 2 year transplant related mortality (Hazard Ratio 1.8, 95% CI, 1.0-2.1, P=0.03) and overall mortality (Hazard Ratio 1.7, 95% CI, 1.2-2.4, P<0.01) than patients with a standard risk graft-versus-host disease. This analysis confirms the Minnesota graft-versus-host disease Risk Score as a valuable bedside tool to define risk in patients with acute graft-versus-host disease. A tailored approach to upfront acute graft-versus-host disease therapy based upon the Minnesota Risk Score may improve outcomes and facilitate testing of novel treatments in these patients.

Outcomes and Predictors of Response in Steroid-Refractory Acute Graft-versus-Host Disease.

The prognosis of steroid-refractory acute graft-versus-host disease (aGVHD) is poor, and predictors of response and survival are unclear. In an exploratory analysis of 203 steroid-refractory aGVHD patients with prospectively collected GVHD data who received antithymocyte globulin, etanercept, or mycophenolate mofetil (MMF) as second-line treatment, we determined the predictors of day 28 response, 2-year overall survival, and 2-year nonrelapse mortality (NRM). To minimize the risk of finding false-positive results, we used least absolute shrinkage and selection operator regression, aggressively eliminating variables that are unlikely to be associated with outcome. Day 28 response to second-line therapy was 38% (complete response, 23%), with a 2-year overall survival of 25% and a 2-year NRM of 62%. Factors associated with response were GVHD prophylaxis, organ involvement, and initial aGVHD to steroid-refractory aGVHD interval. Specifically, compared with cyclosporine/MMF as GVHD prophylaxis, the odds ratio (OR) for calcineurin inhibitor/methotrexate was .8 and for cyclosporine/prednisone .6. The OR for aGVHD to steroid-refractory aGVHD interval ≥ 14 versus <14 days was 1.3. The ORs for skin only involvement and gut or liver only involvement when compared with multiorgan involvement were 1.4 and 1.2, respectively. The only variable associated with worse survival was age, with a hazard ratio (HR) per decade of 1.04 for overall mortality. Similarly, age was the only variable associated with NRM (HR per decade, 1.02). When compared with complete response, no response at day 28 increased the risk of death (HR, 2.4; 95% confidence interval, 1.5 to 3.7). In conclusion, by means of an underused statistical technique in the field of transplantation, we identified predictors of response and survival in steroid-refractory aGVHD. Our results highlight the importance of developing novel treatment strategies because current treatments yield poor outcomes.

Hematopoietic Cell Transplant-Related Toxicities and Mortality in Frail Recipients.

Frailty is a state characterized by diminished physiologic reserve and increased vulnerability to stress and adversely affects outcomes in older patients. We aimed to determine the relationship between pre-hematopoietic cell transplant (HCT) frailty and grades 3 to 4 nonhematologic toxicities (Common Terminology Criteria for Adverse Events, version 5.0) and mortality in HCT recipients within 1 year after HCT and also examined whether age at HCT moderated that association. In a prospective longitudinal study of 117 patients aged ≥ 40 years undergoing HCT, we performed formal pre-HCT geriatric assessments. Frailty was assessed using Fried's criteria. Post-HCT toxicities were abstracted through medical record reviews. The prevalence of pre-HCT frailty was 21% and was not different in younger (40 to 59 years) versus older (≥60 years) HCT recipients. Overall, frail recipients (versus nonfrail) had a higher cumulative incidence of any grades 3 to 4 nonhematologic toxicity (86% [95% confidence interval {CI}, 62% to 100%] versus 70% [95% CI, 57% to 83%), P = .03) and more organ-specific grades 3 to 4 toxicities, such as non-neutropenic infections (38% [95% CI, 17% to 59%] versus 13% [95% CI, 6% to 20%], P < .01), nervous system disorders (19% [95% CI, 3% to 35%] versus 4% [95% CI, 0 to 8%], P = .02), and pneumonia (38% [95% CI, 17% to 59%] versus 10% [95% CI, 4% to 17%], P < .01). Frail recipients were 1.9-fold (95% CI, 1.1 to 3.4) more likely to develop any grades 3 to 4 toxicities (P = .03), 4-fold more likely to suffer non-neutropenic infections (95% CI, 1.4 to 11) and pneumonia (95% CI, 1.4 to 12; both P = .01), and 8.6-fold (95% CI, 1.6 to 45.3) more likely to suffer nervous system disorders (P = .01). Frail allogeneic HCT recipients also had a 3.1 times (95% CI, .9 to 9.7; P = .06) higher risk of overall mortality as compared with nonfrail allogeneic HCT recipients. The higher toxicity and mortality observed in frail allogeneic recipients needs to be monitored with high attention. Studies focusing on interventions to reduce frailty and manage morbidities are needed.

Reduced-Intensity Conditioning Followed by Related and Unrelated Allografts for Hematologic Malignancies: Expanded Analysis and Long-Term Follow-Up.

Reduced-intensity conditioning (RIC) extends the curative potential of allogeneic hematopoietic cell transplantation (HCT) to patients with hematologic malignancies unable to withstand myeloablative conditioning. We prospectively analyzed the outcomes of 292 consecutive patients, median age 58 years (range, 19 to 75) with hematologic malignancies treated with a uniform RIC regimen of cyclophosphamide, fludarabine, and total body irradiation (200 cGy) with or without antithymocyte globulin and cyclosporine and mycophenolate mofetil graft-versus-host disease (GVHD) prophylaxis followed by allogeneic HCT at the University of Minnesota from 2002 to 6. Probability of 5-year overall survival was 78% for patients with indolent non-Hodgkin lymphoma, 53% for chronic myelogenous leukemia, 55% for Hodgkin lymphoma, 40% for acute myelogenous leukemia, 37% for myelodysplastic syndrome, 29% for myeloma, and 14% for myeloproliferative neoplasms. Corresponding outcomes for relapse were 0%, 13%, 53%, 37%, 39%, 75%, and 29%, respectively. Disease risk index (DRI) predicted both survival and relapse with superior survival (64%) and lowest relapse (16%) in those with low risk score compared with 24% survival and 57% relapse in those with high/very-high risk scores. Recipient cytomegalovirus (CMV)-positive serostatus was protective from relapse with the lowest rates in those also receiving a CMV-positive donor graft (29%). The cumulative incidence of 2-year nonrelapse mortality was 26% and was lowest in those receiving a matched sibling graft at 21%, with low (21%) or intermediate (18%) HCT-specific comorbidity index, and was similar across age groups. The incidence of grades II to IV acute GVHD was 43% and grades III to IV 27%; the highest rates were found in those receiving an unrelated donor (URD) peripheral blood stem cell (PBSC) graft, at 50%. Chronic GVHD at 1 year was 36%. Future approaches incorporating alternative GVHD prophylaxis, particularly for URD PBSC grafts, and targeted post-transplant antineoplastic therapies for those with high DRI are indicated to improve these outcomes.

Dynamic Graft-versus-Host Disease-Free, Relapse-Free Survival: Multistate Modeling of the Morbidity and Mortality of Allotransplantation.

Graft-versus-host disease (GVHD)-free, relapse-free survival (GRFS) represents complete, ideal recovery after allogeneic hematopoietic cell transplantation (HCT). However, as originally proposed, this composite endpoint does not account for the possibility that HCT complications may improve after treatment. To more accurately estimate survival with response to GVHD and relapse after HCT, we developed a dynamic multistate GRFS (dGRFS) model with outcomes data from 949 patients undergoing their first allogeneic HCT for hematologic malignancy at the University of Minnesota. Because some patients were successfully treated for GVHD and relapse, dGRFS was higher than the originally defined time-to-event GRFS at 1 year (37.0 versus 27.6%) through 4 years (37.4% versus 22.2%). Mean survival without failure events was .52 years (95% confidence interval, .45 to .58 year) greater in dGRFS compared with the originally defined GRFS. Patient age (P< .001), disease risk (P < .001), conditioning intensity (P = .007), and donor type (P = .003) all significantly influenced dGRFS. The multistate model of dGRFS closely estimates the continuing and prevalent severe morbidity and mortality of allogeneic HCT. To serve the greater HCT community in more accurately modeling recovery from transplantation, we provide our R code for determination of dGRFS with annotations in Supplementary Materials.

Amphiregulin in intestinal acute graft-versus-host disease: a possible diagnostic and prognostic aid.

Amphiregulin, a weak epidermal growth factor receptor agonist, is elevated, while epidermal growth factor, a strong epidermal growth factor receptor agonist, is low in the blood of patients with severe acute graft-versus-host disease. However, the tissue expression and function of these epidermal growth factor receptor ligands in acute graft-versus-host disease target organs is unknown. We compared by immunohistochemistry expression of amphiregulin and epidermal growth factor in archived, formalin-fixed, paraffin-embedded intestinal tissues of 48 patients with biopsy-proven gastrointestinal acute graft-versus-host disease to 3 groups: (1) 10 non-hematopoietic cell transplant normal controls, (2) 11 patients with newly diagnosed ulcerative colitis (ulcerative colitis), (3) 8 patients with a clinical diagnosis of acute graft-versus-host disease despite pathologically non-diagnostic biopsies, (4) and 10 cases of cytomegalovirus colitis. We used a semi-quantitative score of 0 (absent) through 3 (strong) to describe the intensity of immunohistochemical staining. We correlated serum and tissue amphiregulin and epidermal growth factor in patients with acute graft-versus-host disease. Gastrointestinal amphiregulin was significantly lower in acute graft-versus-host disease biopsies (median score 1), ulcerative colitis (median score 1.5), and cytomegalovirus colitis (median score 1) than in normal colon (median score 2, p = 0.004, p = 0.03, p = 0.009 respectively). Amphiregulin expression in was low in 74% of acute graft-versus-host disease cases with or without significant apoptosis. Patients with acute graft-versus-host disease exhibiting the pattern of high gastrointestinal amphiregulin but low serum amphiregulin (n = 14) had the best 1-year survival at 71%, but patients with high serum amphiregulin had poorer survival (<30%) regardless of gastrointestinal amphiregulin expression. Overall, our results lead to the hypothesis that amphiregulin is released into the circulation from damaged intestinal epithelium and stroma, although contributions from other cellular sources are likely. Low gastrointestinal amphiregulin expression by immunohistochemistry may be further studied for its utility in the pathologic acute graft-versus-host disease diagnosis without classic apoptotic changes.

SEMIPARAMETRIC REGRESSION MODEL FOR RECURRENT BACTERIAL INFECTIONS AFTER HEMATOPOIETIC STEM CELL TRANSPLANTATION.

Patients who undergo hematopoietic stem cell transplantation (HSCT) often experience multiple bacterial infections during the early post-transplant period. In this article, we consider a semiparametric regression model that correlates patient- and transplant-related risk factors with inter-infection gap times. Existing regression methods for recurrent gap times are not directly applicable to study post-transplant infection because the initiating event (transplant) is different than the recurrent events of interest (post-transplant infections); as a result, the time from transplant to the first infection and the time elapsed between consecutive infections have distinct biological meanings and hence follow different distributions. Moreover, risk factors may have different effects on these two types of gap times. We propose a semiparametric estimation procedure to evaluate the covariate effects on time from transplant to thefirst infection and on gap times between consecutive infections simultaneously. The proposed estimator accounts for dependent censoring induced by within-subject correlation among recurrent gap times and length bias in the last censored gap time due to intercept sampling. We study the finite sample properties through simulations and present an application of the proposed method to the post-HSCT bacterial infection data collected at the University of Minnesota.

Comparable Outcomes after HLA-Matched Sibling and Alternative Donor Hematopoietic Cell Transplantation for Children with Fanconi Anemia and Severe Aplastic Anemia.

Fanconi anemia (FA)-associated severe aplastic anemia (SAA) requires allogeneic hematopoietic cell transplantation (HCT) for cure. With the evolution of conditioning regimens over time, outcomes of alternative donor HCT (AD-HCT) have improved dramatically. We compared outcomes of HLA-matched sibling donor HCT (MSD-HCT; n = 17) and AD-HCT (n = 57) performed for FA-associated SAA at a single institution between 2001 and 2016. Overall survival at 5 years was 94% for MSD-HCT versus 86% for AD-HCT, neutrophil engraftment was 100% versus 95%, platelet recovery was 100% versus 89%, grade II-IV acute graft-versus-host disease (GVHD) was 6% versus 12%, grade III-IV acute GVHD was 6% versus 4%, and chronic GVHD was 0 versus 7%, with no statistically significant differences by type of transplant. The use of UCB was associated with decreased rates of neutrophil recovery in AD-HCT and platelet recovery in both MSD-HCT and AD-HCT. A trend toward a higher serious infection density before day +100 post-HCT was observed in AD-HCT compared with MSD-HCT (P = .02). These data demonstrate that AD-HCT should be considered at the same time as MSD-HCT for patients with FA-associated SAA.

Pretransplant Gut Colonization with Intrinsically Vancomycin-Resistant Enterococci (E. gallinarum and E. casseliflavus) and Outcomes of Allogeneic Hematopoietic Cell Transplantation.

Pretransplant gut colonization with intrinsically vancomycin-resistant enterococci (iVRE) (Enterococcus gallinarum and Enterococcus casseliflavus) is uncommon and with unknown clinical impact. In a matched-pairs analysis of patients with versus without iVRE colonization (n = 18 in each group), we demonstrated significantly higher 2-year overall survival (86% [95% confidence interval, 52% to 96%] versus 35% [95% confidence interval, 8% to 65]; P <.01) and lower nonrelapse mortality (P <.01) among colonized patients. Putative metabolomes differentiated iVRE from E. faecalis/faecium and may contribute to a healthier gut microbiome in iVRE-colonized patients.

Haploidentical natural killer cells induce remissions in non-Hodgkin lymphoma patients with low levels of immune-suppressor cells.

We report a novel phase 2 clinical trial in patients with poor prognosis refractory non-Hodgkin lymphoma (NHL) testing the efficacy of haploidentical donor natural killer (NK) cell therapy (NK dose 0.5-3.27 × 107 NK cells/kg) with rituximab and IL-2 (clinicaltrials.gov NCT01181258). Therapy was tolerated without graft-versus-host disease, cytokine release syndrome, or neurotoxicity. Of 14 evaluable patients, 4 had objective responses (29%; 95% CI 12-55%) at 2 months: 2 had complete response lasting 3 and 9 months. Circulating donor NK cells persisted for at least 7 days after infusion at the level 0.6-16 donor NK cells/µl or 0.35-90% of total CD56 cells. Responding patients had lower levels of circulating host-derived Tregs (17 ± 4 vs. 307 ± 152 cells/µL; p = 0.008) and myeloid-derived suppressor cells at baseline (6.6 ± 1.4% vs. 13.0 ± 2.7%; p = 0.06) than non-responding patients. Lower circulating Tregs correlated with low serum levels of IL-10 (R 2 = 0.64; p < 0.003; n = 11), suggestive of less immunosuppressive milieu. Low expression of PD-1 on recipient T cells before therapy was associated with response. Endogenous IL-15 levels were higher in responders than non-responding patients at the day of NK cell infusion (mean ± SEM: 30 ± 4; n = 4 vs. 19.0 ± 4.0 pg/ml; n = 8; p = 0.02) and correlated with day 14 NK cytotoxicity as measured by expression of CD107a (R 2 = 0.74; p = 0.0009; n = 12). In summary, our observations support development of donor NK cellular therapies for advanced NHL as a strategy to overcome chemoresistance. Therapeutic efficacy may be further improved through disruption of the immunosuppressive environment and infusion of exogenous IL-15.

Umbilical cord blood-derived T regulatory cells to prevent GVHD: kinetics, toxicity profile, and clinical effect.

We studied the safety and clinical outcomes of patients treated with umbilical cord blood (UCB)-derived regulatory T cells (Tregs) that expanded in cultures stimulated with K562 cells modified to express the high-affinity Fc receptor (CD64) and CD86, the natural ligand of CD28 (KT64/86). Eleven patients were treated with Treg doses from 3-100 × 10(6) Treg/kg. The median proportion of CD4(+)FoxP3(+)CD127(-) in the infused product was 87% (range, 78%-95%), and we observed no dose-limiting infusional adverse events. Clinical outcomes were compared with contemporary controls (n = 22) who received the same conditioning regimen with sirolimus and mycophenolate mofetil immune suppression. The incidence of grade II-IV acute graft-versus-host disease (GVHD) at 100 days was 9% (95% confidence interval [CI], 0-25) vs 45% (95% CI, 24-67) in controls (P = .05). Chronic GVHD at 1 year was zero in Tregs and 14% in controls. Hematopoietic recovery and chimerism, cumulative density of infections, nonrelapse mortality, relapse, and disease-free survival were similar in the Treg recipients and controls. KT64/86-expanded UCB Tregs were safe and resulted in low risk of acute GVHD.

Predictive value of breast magnetic resonance imaging in detecting mammographically occult contralateral breast cancer: Can we target women more likely to have contralateral breast cancer?

BACKGROUND AND OBJECTIVES: Preoperative breast magnetic resonance imaging (B-MRI) staging in newly diagnosed breast cancer increases detection of synchronous contralateral findings, but may result in false-positive outcomes. This study objective was to identify women more likely of having mammographically occult, MRI detected contralateral breast cancer (CBC). METHODS: We performed a retrospective review of patients who had preoperative B-MRI prior to surgery from 2010 to 2015 and collected patient imaging and clinicopathologic data. Multivariate logistic regression was used to identify predictors of CBC. RESULTS: MRI resulted in contralateral findings in 201 of 1894 patients (10.6%). Overall 3.2% (60 of 1894) had synchronous CBC detected on B-MRI. The majority of CBCs (n = 60) were stage 0 or IA (85.0%), hormone receptor positive (94.9%), human epidermal growth factor receptor 2 (HER2/neu) negative (89.7%), and low/intermediate pathological grade (87.2%). Women more likely to have CBC were older (P < .001), had lobular index cancer (P = .03), and estrogen receptor (ER)+ (P = .027) or progesterone receptor (PR)+ (P = .002) tumors. On multivariate analysis (receiver operating characteristic curve area = 0.75), PR + status (P = .022), and older age (P = .004) were predictive of CBC. CONCLUSIONS: Preoperative MRI is most effective in detecting early stage, hormone receptor-positive CBC in older women.

Allele-Level HLA Matching Impacts Key Outcomes Following Umbilical Cord Blood Transplantation for Inherited Metabolic Disorders.

Allogeneic hematopoietic stem cell transplantation has demonstrated efficacy for numerous inherited metabolic disorders (IMDs). Umbilical cord blood transplant (UCBT) is increasingly used as a graft source in IMDs, but little is known of the impact of cord blood unit (CBU)/recipient HLA allelic disparity on key outcomes following UCBT for IMD. We reviewed outcomes of 106 consecutive first, single UCBTs for IMD at the University of Minnesota with regard to CBU/recipient HLA allelic matching (HLA-A, -B, -C, and -DRB1). The median age at UCBT was 1 year, and 87 patients (82%) received myeloablative conditioning. Primary diagnoses were Hurler syndrome (41%), cerebral adrenoleukodystrophy (35%), metachromatic leukodystrophy/globoid cell leukodystrophy (9%), and other (16%). The 5-year overall survival (OS) for the entire cohort was 70% (95% confidence interval, 59% to 79%). Rates of severe acute and chronic graft-versus-host disease were low (6% for each). CBU/recipient HLA conventional matching was based on antigen-level matching at HLA-A and -B, and on allele-level matching at HLA-DRB1. Of 46 conventional matched UCBTs, 20 (43%) were mismatched at 1 or more alleles. Of 49 conventional 5/6 UCBTs, 30 (61%) were mismatched at ≥2 alleles and 19 (39%) were mismatched at ≥3 alleles. Within the 6/6 conventional match stratum, comparisons of key outcomes between allele-matched and allele-mismatched UCBT were as follows: 5-year OS, 88% versus 42% (P < .01); 1-year engrafted survival (ES) with ≥90% donor chimerism, 73% versus 60% (P = .33); graft failure, 8% versus 30% (P = .05); and transplantation-related mortality (TRM), 8% versus 30% (P = .04). For patients undergoing conventional 5/6 HLA-matched UCBT, better allelic matching was associated with similar outcomes: 5-year OS, 77% versus 74% (P = .72); 1-year ES, 73% versus 47% (P = .06); graft failure, 17% versus 42% (P = .05); and TRM, 10% versus 16% (P = .54). On multivariable analyses, fewer allele-level mismatches within each conventional match stratum continued to predict more favorable outcomes following UCBT. These data provide evidence that allele-level HLA matching considerations within a conventional HLA match stratum may better predict outcomes of interest after UCBT for IMD. Larger studies are warranted to confirm these findings and explore other allele-level HLA match dynamics.

Matching at Human Leukocyte Antigen-C Improved the Outcomes after Double Umbilical Cord Blood Transplantation for Recipients of Two to Four of Six Human Leukocyte Antigen-Matched Grafts.

We studied the effect of HLA-C matching in 515 patients after double umbilical cord blood (UCB) transplantation. After HLA matching HLA-A, -B, and -DRB1 at the allele level, we scored patients according to number of donor-recipient HLA-C matches at 4 possible loci: 2 from each donor unit, at the allele level. Given a direct interaction between HLA-A, -B, and -DRB1 matching and HLA-C score, we analyzed HLA-C matching in those receiving at least 1 2/6 to 4/6 HLA-matched unit (n = 389) versus those receiving only 5/6 or 6/6-matched units (n = 126). In those with at least 1 2/6 to 4/6 HLA-matched unit, a better HLA-C matching score was associated with significantly lower risk of death of any cause and nonrelapse mortality and better disease-free survival. There was no association with the risk of relapse, acute and chronic graft-versus-host disease, and hematopoietic recovery. In contrast, among patients receiving only allele-level 5/6 or 6/6 HLA-matched UCB units, HLA-C match had no demonstrable effect on any outcome. For patients receiving at least 1 allele-level 2/6 to 4/6 HLA-matched UCB unit, matching at HLA-C reduces nonrelapse mortality and improves survival.

Alternative donor hematopoietic cell transplantation for Fanconi anemia.

Historically, alternative donor hematopoietic cell transplantation (HCT) for Fanconi anemia (FA) patients resulted in excessive morbidity and mortality. To improve outcomes, we made sequential changes to the HCT conditioning regimen. A total of 130 FA patients (median age, 9.0 years; range, 1-48) underwent alternative donor HCT at the University of Minnesota between 1995 and 2012. All patients received cyclophosphamide (CY), single fraction total body irradiation (TBI), and antithymocyte globulin (ATG) with or without fludarabine (FLU), followed by T-cell-depleted bone marrow or unmanipulated umbilical cord blood transplantation. The addition of FLU enhanced engraftment 3-fold. The incidence of grades 2-4 acute and chronic graft-versus-host disease was 20% and 10%, respectively. Severe toxicity was highest in patients >10 years of age or those with a history of opportunistic infections or transfusions before HCT. Mortality was lowest in patients without a history of opportunistic infection or transfusions and who received conditioning with TBI 300 cGy, CY, FLU, and ATG. These patients had a probability of survival of 94% at 5 years. Alternative donor HCT is now associated with excellent survival for patients without prior opportunistic infections or transfusions and should be considered for all FA patients after the onset of marrow failure. These studies were registered at http://www.clinicaltrials.gov as NCT00005898, NCT00167206, and NCT00352976.