Gemtuzumab ozogamicin plus midostaurin in combination with standard '7 + 3' induction therapy in newly diagnosed AML: Results from the SAL-MODULE phase I study.

We conducted a phase I trial in newly diagnosed acute myeloid leukaemia (AML) to investigate the combination of two novel targeted agents, gemtuzumab ozogamicin (GO) and midostaurin, with intensive chemotherapy in FLT3-mutated AML and CBF leukaemia. Three dose levels of midostaurin and one to three sequential doses of 3 mg/m2 GO in combination with '7 + 3' induction were evaluated. Based on safety findings in 12 patients, our results show that 3 mg/m2 GO on Days 1 + 4 and 100 mg midostaurin on Days 8-21 can be safely combined with IC in newly diagnosed AML.

Phase Ib study of sabatolimab (MBG453), a novel immunotherapy targeting TIM-3 antibody, in combination with decitabine or azacitidine in high- or very high-risk myelodysplastic syndromes.

The safety and efficacy of sabatolimab, a novel immunotherapy targeting T-cell immunoglobulin domain and mucin domain-3 (TIM-3), was assessed in combination with hypomethylating agents (HMAs) in patients with HMA-naive revised International Prognostic System Score (IPSS-R) high- or very high-risk myelodysplastic syndromes (HR/vHR-MDS) or chronic myelomonocytic leukemia (CMML). Sabatolimab + HMA had a safety profile similar to that reported for HMA alone and demonstrated durable clinical responses in patients with HR/vHR-MDS. These results support the ongoing evaluation of sabatolimab-based combination therapy in MDS, CMML, and acute myeloid leukemia.

In Vitro Functionality and Endurance of GMP-Compliant Point-of-Care BCMA.CAR-T Cells at Different Timepoints of Cryopreservation.

The search for target antigens for CAR-T cell therapy against multiple myeloma defined the B-cell maturation antigen (BCMA) as an interesting candidate. Several studies with BCMA-directed CAR-T cell therapy showed promising results. Second-generation point-of-care BCMA.CAR-T cells were manufactured to be of a GMP (good manufacturing practice) standard using the CliniMACS Prodigy® device. Cytokine release in BCMA.CAR-T cells after stimulation with BCMA positive versus negative myeloma cell lines, U266/HL60, was assessed via intracellular staining and flow cytometry. The short-term cytotoxic potency of CAR-T cells was evaluated by chromium-51 release, while the long-term potency used co-culture (3 days/round) at effector/target cell ratios of 1:1 and 1:4. To evaluate the activation and exhaustion of CAR-T cells, exhaustion markers were assessed via flow cytometry. Stability was tested through a comparison of these evaluations at different timepoints: d0 as well as d + 14, d + 90 and d + 365 of cryopreservation. As results, (1) Killing efficiency of U266 cells correlated with the dose of CAR-T cells in a classical 4 h chromium-release assay. There was no significant difference after cryopreservation on different timepoints. (2) In terms of endurance of BCMA.CAR-T cell function, BCMA.CAR-T cells kept their ability to kill all tumor cells over six rounds of co-culture. (3) BCMA.CAR-T cells released high amounts of cytokines upon stimulation with tumor cells. There was no significant difference in cytokine release after cryopreservation. According to the results, BCMA.CAR-T cells manufactured under GMP conditions exerted robust and specific killing of target tumor cells with a high release of cytokines. Even after 1 year of cryopreservation, cytotoxic functions were maintained at the same level. This gives clinicians sufficient time to adjust the timepoint of BCMA.CAR-T cell application to the patient's course of the underlying disease.

Mobocertinib in Patients with EGFR Exon 20 Insertion-Positive Non-Small Cell Lung Cancer (MOON): An International Real-World Safety and Efficacy Analysis.

EGFR exon 20 (EGFR Ex20) insertion mutations in non-small cell lung cancer (NSCLC) are insensitive to traditional EGFR tyrosine kinase inhibitors (TKIs). Mobocertinib is the only approved TKI specifically designed to target EGFR Ex20. We performed an international, real-world safety and efficacy analysis on patients with EGFR Ex20-positive NSCLC enrolled in a mobocertinib early access program. We explored the mechanisms of resistance by analyzing postprogression biopsies, as well as cross-resistance to amivantamab. Data from 86 patients with a median age of 67 years and a median of two prior lines of treatment were analyzed. Treatment-related adverse events (TRAEs) occurred in 95% of patients. Grade ≥3 TRAEs were reported in 38% of patients and included diarrhea (22%) and rash (8%). In 17% of patients, therapy was permanently discontinued, and two patients died due to TRAEs. Women were seven times more likely to discontinue treatment than men. In the overall cohort, the objective response rate to mobocertinib was 34% (95% CI, 24-45). The response rate in treatment-naïve patients was 27% (95% CI, 8-58). The median progression-free and overall survival was 5 months (95% CI, 3.5-6.5) and 12 months (95% CI, 6.8-17.2), respectively. The intracranial response rate was limited (13%), and one-third of disease progression cases involved the brain. Mobocertinib also showed antitumor activity following EGFR Ex20-specific therapy and vice versa. Potential mechanisms of resistance to mobocertinib included amplifications in MET, PIK3CA, and NRAS. Mobocertinib demonstrated meaningful efficacy in a real-world setting but was associated with considerable gastrointestinal and cutaneous toxicity.

Flotetuzumab as salvage immunotherapy for refractory acute myeloid leukemia.

Approximately 50% of acute myeloid leukemia (AML) patients do not respond to induction therapy (primary induction failure [PIF]) or relapse after <6 months (early relapse [ER]). We have recently shown an association between an immune-infiltrated tumor microenvironment (TME) and resistance to cytarabine-based chemotherapy but responsiveness to flotetuzumab, a bispecific DART antibody-based molecule to CD3ε and CD123. This paper reports the results of a multicenter, open-label, phase 1/2 study of flotetuzumab in 88 adults with relapsed/refractory AML: 42 in a dose-finding segment and 46 at the recommended phase 2 dose (RP2D) of 500 ng/kg per day. The most frequent adverse events were infusion-related reactions (IRRs)/cytokine release syndrome (CRS), largely grade 1-2. Stepwise dosing during week 1, pretreatment dexamethasone, prompt use of tocilizumab, and temporary dose reductions/interruptions successfully prevented severe IRR/CRS. Clinical benefit accrued to PIF/ER patients showing an immune-infiltrated TME. Among 30 PIF/ER patients treated at the RP2D, the complete remission (CR)/CR with partial hematological recovery (CRh) rate was 26.7%, with an overall response rate (CR/CRh/CR with incomplete hematological recovery) of 30.0%. In PIF/ER patients who achieved CR/CRh, median overall survival was 10.2 months (range, 1.87-27.27), with 6- and 12-month survival rates of 75% (95% confidence interval [CI], 0.450-1.05) and 50% (95% CI, 0.154-0.846). Bone marrow transcriptomic analysis showed that a parsimonious 10-gene signature predicted CRs to flotetuzumab (area under the receiver operating characteristic curve = 0.904 vs 0.672 for the European LeukemiaNet classifier). Flotetuzumab represents an innovative experimental approach associated with acceptable safety and encouraging evidence of activity in PIF/ER patients. This trial was registered at www.clinicaltrials.gov as #NCT02152956.

Chimeric antigen receptor T-cell therapy in acute myeloid leukemia.

PURPOSE OF REVIEW: Treatment outcome of relapsed or refractory AML patients remains dismal and new treatment options are needed. Adoptive cell therapy using CAR-T cells is a potentially interesting approach in this. RECENT FINDINGS: Several potentially interesting AML targets are being investigated with CAR-T therapy with over 60 clinical trials listed on clinicaltrials.gov. The first clinical data are only just emerging with mixed results, once more proving that further research is needed. SUMMARY: Adoptive cell therapy using chimeric antigen receptor T cells is being investigated in AML through many clinical trials. So far, no AML-specific antigen has been identified, requiring additional strategies to mitigate on-target off-tumor toxicity and to increase efficacy. Focus point is to acquire control over the CAR T cells once administered. Strategies to do so include biodegradable CARs, inducible CARs, suicide-switch containing CARs and two-component modular CARs. Limited and mixed results are available, confirming the risk of lasting toxicity for nonswitchable CARs. Initial results of modular CARs suggest toxicity can be mitigated whilst maintaining CAR activity by the use of modular CAR concepts that allows for 'ON' and 'OFF' switching.

Deciphering the immunosuppressive tumor microenvironment in ALK- and EGFR-positive lung adenocarcinoma.

INTRODUCTION: The advent of immune checkpoint blockade (ICB) has led to significantly improved disease outcome in lung adenocarcinoma (ADC), but response of ALK/EGFR-positive tumors to immune therapy is limited. The underlying immune biology is incompletely understood. METHODS: We performed comparative mRNA expression profiling of 31 ALK-positive, 40 EGFR-positive and 43 ALK/EGFR-negative lung ADC focused on immune gene expression. The presence and levels of tumor infiltration lymphocytes (TILs) as well as fourteen specific immune cell populations were estimated from the gene expression profiles. RESULTS: While total TILs were not lower in ALK-positive and EGFR-positive tumors compared to ALK/EGFR-negative tumors, specific immunosuppressive characteristics were detected in both subgroups: In ALK-positive tumors, regulatory T cells were significantly higher compared to EGFR-positive (fold change: FC = 1.9, p = 0.0013) and ALK/EGFR-negative tumors (FC = 2.1, p = 0.00047). In EGFR-positive tumors, cytotoxic cells were significantly lower compared to ALK-positive (FC = - 1.7, p = 0.016) and to ALK/EGFR-negative tumors (FC = - 2.1, p = 2.0E-05). A total number of 289 genes, 40 part of cytokine-cytokine receptor signaling, were differentially expressed between the three subgroups. Among the latter, five genes were differently expressed in both ALK-positive and EGFR-positive tumors, while twelve genes showed differential expression solely in ALK-positive tumors and eleven genes solely in EGFR-positive tumors. CONCLUSION: Targeted gene expression profiling is a promising tool to read out tumor microenvironment characteristics from routine diagnostic lung cancer biopsies. Significant immune reactivity including specific immunosuppressive characteristics in ALK- and EGFR-positive lung ADC, but not a total absence of immune infiltration supports further clinical evaluation of immune-modulators as partners of ICB in such tumors.

Volasertib as a monotherapy or in combination with azacitidine in patients with myelodysplastic syndrome, chronic myelomonocytic leukemia, or acute myeloid leukemia: summary of three phase I studies.

BACKGROUND: This report summarizes three phase I studies evaluating volasertib, a polo-like kinase inhibitor, plus azacitidine in adults with myelodysplastic syndromes (MDS), chronic myelomonocytic leukemia, or acute myeloid leukemia. METHODS: Patients received intravenous volasertib in 28-day cycles (dose-escalation schedules). In Part 1 of 1230.33 (Study 1; NCT01957644), patients received 250-350 mg volasertib on day (D)1 and D15; in Part 2, patients received different schedules [A, D1: 170 mg/m2; B, D7: 170 mg/m2; C, D1 and D7: 110 mg/m2]. In 1230.35 (Study 2; NCT02201329), patients received 200-300 mg volasertib on D1 and D15. In 1230.43 (Study 3; NCT02721875), patients received 110 mg/m2 volasertib on D1 and D8. All patients in Studies 1 and 2, and approximately half of the patients in Study 3, were scheduled to receive subcutaneous azacitidine 75 mg/m2 on D1-7. RESULTS: Overall, 22 patients were treated (17 with MDS; 12 previously untreated). Across Studies 1 and 2 (n = 21), the most common drug-related adverse events were hematological (thrombocytopenia [n = 11]; neutropenia [n = 8]). All dose-limiting toxicities were grade 4 thrombocytopenia. The only treated patient in Study 3 experienced 18 adverse events following volasertib monotherapy. Studies 1 and 2 showed preliminary activity (objective response rates: 25 and 40%). CONCLUSIONS: The safety of volasertib with azacitidine in patients with MDS was consistent with other volasertib studies. All studies were terminated prematurely following the discontinuation of volasertib for non-clinical reasons by Boehringer Ingelheim; however, safety information on volasertib plus azacitidine are of interest for future studies in other diseases.

Phase I trial of the DLL3/CD3 bispecific T-cell engager BI 764532 in DLL3-positive small-cell lung cancer and neuroendocrine carcinomas.

Poorly differentiated neuroendocrine carcinomas such as small-cell lung cancer (SCLC) have poor survival and high relapse rates. DLL3 is found on these carcinomas and has become a target of increasing interest in recent years. The bispecific DLL3/CD3 T-cell engager BI 764532 has been shown to induce complete tumor regression in a human T cell-engrafted mouse model. Here, we describe the study design of a first-in-human, phase I, multicenter, open-label, non-randomized, dose-escalation study in patients with SCLC or other DLL3-positive neuroendocrine carcinomas. The study will determine the maximum tolerated dose and evaluate safety, tolerability, pharmacokinetics and preliminary efficacy of BI 764532 monotherapy.

DLL3 is a protein involved in development of the embryo during pregnancy. It has also been found on the surface of cells involved in the development of certain types of lung cancer and other tumors. The T-cell engager BI 764532 binds to DLL3 and cells of the immune system simultaneously, resulting in the death of tumor cells. Here we describe the rationale for, and design of, a clinical study of BI 764532 in patients with small-cell lung cancer and other tumors containing DLL3. The aim of the study is to find the highest acceptable dose of BI 764532 that can be tolerated by patients, and explore the safety and efficacy of BI 764532. Clinical Trial Registration: NCT04429087 (ClinicalTrials.gov).

Comparison of FACS and PCR for Detection of BCMA-CAR-T Cells.

Chimeric-antigen-receptor (CAR)-T-cell therapy is already widely used to treat patients who are relapsed or refractory to chemotherapy, antibodies, or stem-cell transplantation. Multiple myeloma still constitutes an incurable disease. CAR-T-cell therapy that targets BCMA (B-cell maturation antigen) is currently revolutionizing the treatment of those patients. To monitor and improve treatment outcomes, methods to detect CAR-T cells in human peripheral blood are highly desirable. In this study, three different detection reagents for staining BCMA-CAR-T cells by flow cytometry were compared. Moreover, a quantitative polymerase chain reaction (qPCR) to detect BCMA-CAR-T cells was established. By applying a cell-titration experiment of BCMA-CAR-T cells, both methods were compared head-to-head. In flow-cytometric analysis, the detection reagents used in this study could all detect BCMA-CAR-T cells at a similar level. The results of false-positive background staining differed as follows (standard deviation): the BCMA-detection reagent used on the control revealed a background staining of 0.04% (±0.02%), for the PE-labeled human BCMA peptide it was 0.25% (±0.06%) and for the polyclonal anti-human IgG antibody it was 7.2% (±9.2%). The ability to detect BCMA-CAR-T cells down to a concentration of 0.4% was similar for qPCR and flow cytometry. The qPCR could detect even lower concentrations (0.02-0.01%). In summary, BCMA-CAR-T-cell monitoring can be reliably performed by both flow cytometry and qPCR. In flow cytometry, reagents with low background staining should be preferred.

Phase 1b/2 trial of tepotinib in sorafenib pretreated advanced hepatocellular carcinoma with MET overexpression.

BACKGROUND: This Phase 1b/2 study evaluated tepotinib, a highly selective MET inhibitor, in US/European patients with sorafenib pretreated advanced hepatocellular carcinoma (aHCC) with MET overexpression. METHODS: Eligible adults had aHCC, progression after ≥4 weeks of sorafenib, and, for Phase 2 only, MET overexpression. Tepotinib was administered once daily at 300 or 500 mg in Phase 1b ('3 + 3' design), and at the recommended Phase 2 dose (RP2D) in Phase 2. Primary endpoints were dose-liming toxicities (DLTs; Phase 1b) and 12-week investigator-assessed progression-free survival (PFS; Phase 2). RESULTS: In Phase 1b (n = 17), no DLTs occurred and the RP2D was confirmed as 500 mg. In Phase 2 (n = 49), the primary endpoint was met: 12-week PFS was 63.3% (90% CI: 50.5-74.7), which was significantly greater than the predefined null hypothesis of ≤15% (one-sided binomial exact test: P < 0.0001). Median time to progression was 4 months. In Phase 2, 28.6% of patients had treatment-related Grade ≥3 adverse events, including peripheral oedema and lipase increase (both 6.1%). CONCLUSIONS: Tepotinib was generally well tolerated and the RP2D (500 mg) showed promising efficacy and, therefore, a positive benefit-risk balance in sorafenib pretreated aHCC with MET overexpression. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02115373.

Earlier corticosteroid use for adverse event management in patients receiving axicabtagene ciloleucel for large B-cell lymphoma.

Axicabtagene ciloleucel (axi-cel) is an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy approved for relapsed or refractory large B-cell lymphoma (R/R LBCL). To reduce axi-cel-related toxicity, several exploratory safety management cohorts were added to ZUMA-1 (NCT02348216), the pivotal phase 1/2 study of axi-cel in refractory LBCL. Cohort 4 evaluated the rates and severity of cytokine release syndrome (CRS) and neurologic events (NEs) with earlier corticosteroid and tocilizumab use. Primary endpoints were incidence and severity of CRS and NEs. Patients received 2 × 106 anti-CD19 CAR T cells/kg after conditioning chemotherapy. Forty-one patients received axi-cel. Incidences of any-grade CRS and NEs were 93% and 61%, respectively (grade ≥ 3, 2% and 17%). There was no grade 4 or 5 CRS or NE. Despite earlier dosing, the cumulative cortisone-equivalent corticosteroid dose in patients requiring corticosteroid therapy was lower than that reported in the pivotal ZUMA-1 cohorts. With a median follow-up of 14·8 months, objective and complete response rates were 73% and 51%, respectively, and 51% of treated patients were in ongoing response. Earlier and measured use of corticosteroids and/or tocilizumab has the potential to reduce the incidence of grade ≥ 3 CRS and NEs in patients with R/R LBCL receiving axi-cel.

Reliable isolation of human mesenchymal stromal cells from bone marrow biopsy specimens in patients after allogeneic hematopoietic cell transplantation.

Isolation of mesenchymal stromal cells (MSCs) from pretreated, hematologic patients is challenging. Especially after allogeneic hematopoietic cell transplantation (HCT), standard protocols using bone marrow aspirates fail to reliably recover sufficient cell numbers. Because MSCs are considered to contribute to processes that mainly affect the outcome after transplantation, such as an efficient lymphohematopoietic recovery, extent of graft-versus-host disease as well as the occurrence of leukemic relapse, it is of great clinical relevance to investigate MSC function in this context. Previous studies showed that MSCs can be isolated by collagenase digestion of large bone fragments of hematologically healthy patients undergoing hip replacement or knee surgeries. We have now further developed this procedure for the isolation of MSCs from hematologic patients after allogeneic HCT by using trephine biopsy specimens obtained during routine examinations. Comparison of aspirates and trephine biopsy specimens from patients after allogeneic HCT revealed a significantly higher frequency of clonogenic MSCs (colony-forming unit-fibroblast [CFU-F]) in trephine biopsy specimens (mean, 289.8 ± standard deviation 322.5 CFU-F colonies/1 × 106 total nucleated cells versus 4.2 ± 9.9; P < 0.0001). Subsequent expansion of functional MSCs isolated from trephine biopsy specimen was more robust and led to a significantly higher yield compared with control samples expanded from aspirates (median, 1.6 × 106; range, 0-2.3 × 107 P0 MSCs versus 5.4 × 104; range, 0-8.9 × 106; P < 0.0001). Using trephine biopsy specimens as MSC source facilitates the investigation of various clinical questions.

Ramucirumab plus pembrolizumab in patients with previously treated advanced non-small-cell lung cancer, gastro-oesophageal cancer, or urothelial carcinomas (JVDF): a multicohort, non-randomised, open-label, phase 1a/b trial.

BACKGROUND: Pre-clinical and clinical evidence suggests that simultaneous blockade of VEGF receptor-2 (VEGFR-2) and PD-1 or PD-L1 enhances antigen-specific T-cell migration, antitumour activity, and has favourable toxicity. In this study, we aimed to assess the safety and preliminary antitumour activity of ramucirumab (an IgG1 VEGFR-2 antagonist) combined with pembrolizumab (an IgG4 PD-1 antagonist) in patients with previously treated advanced gastric or gastro-oesophageal junction adenocarcinoma, non-small-cell lung cancer, or urothelial carcinoma. METHODS: We did a multicohort, non-randomised, open-label, phase 1a/b trial at 16 academic medical centres, hospitals, and clinics in the USA, France, Germany, Spain, and the UK. We enrolled adult patients aged 18 years or older with histologically confirmed gastric or gastro-oesophageal junction adenocarcinoma (cohorts A and B), non-small-cell lung cancer (cohort C), or urothelial carcinoma (cohort D), whose disease had progressed on one or two lines of previous therapy (for those with gastric or gastro-oesophageal junction adenocarcinoma) or one to three lines of previous therapy (for those with non-small-cell lung cancer and urothelial carcinoma) that included platinum (for all tumour types) or fluoropyrimidine or both (for gastric or gastro-oesophageal junction adenocarcinoma). Eligibility criteria included presence of measurable disease and an Eastern Cooperative Oncology Group performance status of 0-1. Patients with previously untreated gastric or gastro-oesophageal junction adenocarcinoma and non-small-cell lung cancer were also enrolled (in two additional separate cohorts); the results for these cohorts will be reported separately. The first 21-day treatment cycle was a dose-limiting toxicity observation period (phase 1a; safety run-in), followed by a phase 1b cohort expansion stage. Pembrolizumab 200 mg was administered intravenously on day 1, and intravenous ramucirumab was administered at 8 mg/kg on days 1 and 8 for cohort A or at 10 mg/kg on day 1 for cohorts B, C, and D, every 3 weeks, until disease progression or other discontinuation criteria were met. The primary endpoint was the safety and tolerability of ramucirumab in combination with pembrolizumab assessed by the incidence of adverse events in both phase 1a and 1b and as dose-limiting toxicities during phase 1a. The safety and activity analysis set included all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov, number NCT02443324, and is no longer enrolling patients. FINDINGS: Between July 30, 2015 and June 24, 2016, we enrolled and treated 92 patients (41 with gastric or gastro-oesophageal junction adenocarcinoma, 27 with non-small-cell lung cancer, and 24 with urothelial carcinoma). Median follow-up was 32·8 months (IQR 28·1-33·6). During the first cycle of treatment (phase 1a safety run-in; n=11), one patient with gastro-oesophageal junction adenocarcinoma who received the 8 mg/kg dose of ramucirumab had grade 3 abdominal pain, colitis, hepatitis, interstitial lung disease, and jaundice, and grade 4 cholestasis, and died on treatment on day 40; the death was deemed related to progressive disease. No additional dose-limiting toxicities occurred and the decision was made to maintain the full planned doses of ramucirumab and pembrolizumab in phase 1b (n=81). Treatment-related adverse events occurred in 75 (82%) of 92 patients, the most common of which was fatigue (in 33 patients [36%]), predominantly of grade 1 or 2 severity. 22 patients (24%) had one or more treatment-related adverse events of grade 3 or worse, most commonly hypertension (six patients; 7%) and colitis (five patients; 5%). Serious adverse events occurred in 53 (58%) of 92 patients, and were deemed related to treatment in 22 (24%) patients. The most common treatment-related serious adverse events were abdominal pain in patients with gastric or gastro-oesophageal junction adenocarcinoma (in three [7%] of 41 patients); asthenia and myocardial infarction in patients with non-small-cell lung cancer (two [7%] of 27 patients), and colitis in patients with urothelial carcinoma (two [8%] of 24 patients). Six (7%) of 92 patients discontinued treatment because of treatment-related adverse events, and one death (from pulmonary sepsis in a patient with gastric or gastro-oesophageal junction adenocarcinoma) was deemed related to treatment. The number of patients achieving an objective response was three (7%; 95% CI 1·5-19·9) of 41 in the gastric or gastro-oesophageal junction adenocarcinoma cohort, eight (30%; 13·8-50·2) of 27 in the non-small-cell lung cancer cohort, and three (13%, 2·7-32·4) in the urothelial carcinoma cohort. INTERPRETATION: Ramucirumab in combination with pembrolizumab showed a manageable safety profile with favourable antitumour activity in patients with previously treated advanced gastric or gastro-oesophageal junction adenocarcinoma, non-small-cell lung cancer, and urothelial carcinoma. Our results contribute to the growing evidence that supports dual inhibition of the VEGF-VEGFR2 and PD-1-PD-L1 pathways. This combination could be further explored with or without chemotherapy, especially for patients with tumours for which single-agent checkpoint inhibitors have shown no additional benefit over chemotherapy. FUNDING: Eli Lilly and Company, and Merck and Co.

Validation of the Revised Pretransplant Assessment of Mortality Score in Patients with Acute Myelogenous Leukemia Undergoing Allogeneic Hematopoietic Stem Cell Transplantation.

Despite recent advances, allogeneic hematopoietic stem cell transplantation (allo-HSCT) continues to be accompanied by a high rate of morbidity and mortality. Several scores have been developed to predict outcome after allo-HSCT. The recently revised Pretransplant Assessment of Mortality (PAM) score is based on patient age, donor type, disease risk, cytomegalovirus (CMV) serostatus of patient and donor, and forced expiratory volume in 1 second (FEV1). The aim of this study was to analyze the predictive power of the PAM score in an independent large cohort of patients with acute myelogenous leukemia (AML). We selected adult patients with AML who underwent a first allo-HSCT at the University Hospital of Dresden, a tertiary care hospital with a large transplantation program. All adult patients treated between January 1, 2003, and July 1, 2015, were included. The PAM score was calculated as described previously. Overall survival (OS), cumulative incidence of relapse (CIR), and nonrelapse mortality (NRM) after allo-HSCT were analyzed. Age, AML type, sex match, CMV match, donor type, European Leukemia Net risk classification, type of conditioning, disease stage, and PAM score as a continuous variable were selected a priori for multivariate Cox regression analyses. A total of 544 patients met the inclusion criteria. The median patient age was 57 years. With a median follow-up of 47 months (range, 1 to 161 months), the estimated OS for the whole cohort at 4 years was 43%, with a CIR of 30% and an NRM of 31%. The probability of OS at 4 years was 65% for patients with a PAM score of 0, 52% in those with a PAM score of 1, 33% in those with a PAM score of 2, and 22% in those with a PAM score of 3 (P < .001, log-rank test). Both the CIR and NRM increased with higher PAM scores (P = .005 and P < .001, respectively, Gray test). In multivariate analysis, age (hazard ratio [HR], 1.02 per year; P = .004), disease stage (primary induction failure versus first complete remission (CR1); HR, 1.5; P = .03), and the PAM score (HR 1.04; P = .03) had a significant impact on OS. This is the first independent validation of the revised PAM score allowing for simple and valid estimation of transplantation outcomes. It can serve as an important tool in counseling patients with AML, as well as in designing future trials.

RNAi profiling of primary human AML cells identifies ROCK1 as a therapeutic target and nominates fasudil as an antileukemic drug.

Acute myeloid leukemia (AML) is characterized by a marked genetic heterogeneity, which complicates the development of novel therapeutics. The delineation of pathways essential within an individual patient's mutational background might overcome this limitation and facilitate personalized treatment. We report the results of a large-scale lentiviral loss-of-function RNA interference (RNAi) screen in primary leukemic cells. Stringent validation identified 6 genes (BNIPL1, ROCK1, RPS13, STK3, SNX27, WDHD1) whose knockdown impaired growth and viability of the cells. Dependence on these genes was not caused by mutation or overexpression, and although some of the candidates seemed to be rather patient specific, others were essential in cells isolated from other AML patients. In addition to the phenotype observed after ROCK1 knockdown, treatment with the approved ROCK inhibitor fasudil resulted in increased apoptosis and decreased viability of primary AML cells. In contrast to observations in some other malignancies, ROCK1 inhibition did not foster growth of immature malignant progenitors but was toxic to this cell fraction in feeder coculture and xenotransplant experiments, indicating a distinct effect of ROCK1 inhibition on leukemic progenitors. We conclude that large-scale RNAi screens in primary patient-derived cells are feasible and can complement other methods for personalized cancer therapies, such as expression and mutation profiling.

Mesenchymal Stromal Cells for Treatment of Acute Steroid-Refractory Graft Versus Host Disease: Clinical Responses and Long-Term Outcome.

Acute graft-versus-host disease (aGvHD) remains a major cause of morbidity and mortality after allogeneic hematopoietic stem cell transplantation. Steroid-resistant aGvHD is associated with poor outcome, and no commonly accepted salvage therapy is available for its treatment. Here, we report 58 adult patients treated with mesenchymal stromal cells (MSCs) as salvage therapy for steroid-refractory aGvHD. Third-party MSCs expanded in platelet lysate-containing medium were transfused at a median dose of 0.99 × 10(6) cells per kg b.wt. A median of two MSC infusions were administered to each patient. Median time between the onset of aGvHD and the first infusion of MSCs was 12 days (range, 6-62 days). Most patients (79%) had grade IV aGvHD. Five patients showed complete response, five showed very good partial response, 17 showed partial response, and 31 showed no response. The estimated probability of survival after 1 year was 19%, and median survival was 69 days. Overall survival was not significantly different from that of a historical cohort of patients receiving alternative salvage therapy and no MSC infusions. In conclusion, MSC treatment on top of conventional immunosuppression was associated with an overall response rate of 47% but improved outcome in terms of survival remains to be shown.