Graciela Nogueras Gonzalez

Results of the Phase I Trial of RG7112, a Small-Molecule MDM2 Antagonist in Leukemia.

Purpose: RG7112 is a small-molecule MDM2 antagonist. MDM2 is a negative regulator of the tumor suppressor p53 and frequently overexpressed in leukemias. Thus, a phase I study of RG7112 in patients with hematologic malignancies was conducted. Experimental Design: Primary study objectives included determination of the dose and safety profile of RG7112. Secondary objectives included evaluation of pharmacokinetics; pharmacodynamics, such as TP53-mutation status and MDM2 expression; and preliminary clinical activity. Patients were divided into two cohorts: Stratum A [relapsed/refractory acute myeloid leukemia (AML; except acute promyelocytic leukemia), acute lymphoblastic leukemia, and chronic myelogenous leukemia] and Stratum B (relapsed/refractory chronic lymphocytic leukemia/small cell lymphocytic leukemia; CLL/sCLL). Some Stratum A patients were treated at the MTD to assess clinical activity. Results: RG7112 was administered to 116 patients (96 patients in Stratum A and 20 patients in Stratum B). All patients experienced at least 1 adverse event, and 3 dose-limiting toxicities were reported. Pharmacokinetic analysis indicated that twice-daily dosing enhanced daily exposure. Antileukemia activity was observed in the 30 patients with AML assessed at the MTD, including 5 patients who met International Working Group (IWG) criteria for response. Exploratory analysis revealed TP53 mutations in 14% of Stratum A patients and in 40% of Stratum B patients. Two patients with TP53 mutations exhibited clinical activity. p53 target genes were induced only in TP53 wild-type leukemic cells. Baseline expression levels of MDM2 correlated positively with clinical response. Conclusions: RG7112 demonstrated clinical activity against relapsed/refractory AML and CLL/sCLL. MDM2 inhibition resulted in p53 stabilization and transcriptional activation of p53-target genes. We provide proof-of-concept that MDM2 inhibition restores p53 function and generates clinical responses in hematologic malignancies. Clin Cancer Res; 22(4); 868–76. ©2015 AACR.

Safety of Presurgical Targeted Therapy in the Setting of Metastatic Renal Cell Carcinoma

BACKGROUND In patients with metastatic renal cell carcinoma (mRCC), the timing of systemic targeted therapy in relation to cytoreductive nephrectomy (CN) is under investigation. OBJECTIVE To evaluate postoperative complications after the use of presurgical targeted therapy prior to CN. DESIGN, SETTING, AND PARTICIPANTS A retrospective review of all patients who underwent a CN at The University of Texas M.D. Anderson Cancer Center from 2004 to 2010 was performed. Inclusion in this study required documented evidence of mRCC, with treatment incorporating CN. INTERVENTIONS Patients receiving presurgical systemic targeted therapy prior to CN were compared to those undergoing immediate CN. MEASUREMENTS Complications were assessed using the modified Clavien system for a period of 12 mo postoperatively. RESULTS AND LIMITATIONS Presurgical therapy was administered to 70 patients prior to CN (presurgical), while 103 patients had an immediate CN (immediate). A total of 232 complications occurred in 57% of patients (99 of 173). Use of presurgical systemic targeted therapy was predictive of having a complication>90 d postoperatively (p=0.002) and having multiple complications (p=0.013), and it was predictive of having a wound complication (p<0.001). Despite these specific complications, presurgical systemic targeted therapy was not associated with an increased overall complication risk on univariable or multivariate analysis (p=0.064 and p=0.237) and was not predictive for severe (Clavien ≥3) complications (p=0.625). This study is limited by its retrospective nature. As is inherent to any retrospective study reporting on complications, we are limited by reporting bias and the potential for misclassification of specific complications. CONCLUSIONS Despite an increased risk for specific wound-related complications, overall surgical complications and the risk of severe complications (Clavien ≥3) are not greater after presurgical targeted therapy in comparison to upfront cytoreductive surgery.

Cytokine Panel for Response to Intravesical Therapy (CyPRIT): Nomogram of Changes in Urinary Cytokine Levels Predicts Patient Response to Bacillus Calmette-Guérin

UNLABELLED The response of non-muscle-invasive bladder cancer (NMIBC) to intravesical immunotherapy with bacillus Calmette-Guérin (BCG) depends on adequate stimulation of an immune response. Although BCG has been used for decades, we lack tools to accurately predict response in individual patients. To address this deficiency, we initiated a clinical trial in patients with intermediate- and high-risk NMIBC. BCG was administered according to the Southwest Oncology Group protocol. Urine samples were collected for cytokine assay at baseline, immediately before and after BCG instillation at 6 wk, and immediately before and after the third BCG instillation of the first maintenance course. Levels of 12 cytokines were measured, and changes from baseline were calculated after treatment. A total of 130 patients were enrolled. Increases in single cytokines correlated with recurrence, but the best predictor of recurrence was changes in a combination of cytokines. A nomogram (CyPRIT) constructed using urinary levels of nine inducible cytokines (IL-2, IL-6, IL-8, IL-18, IL-1ra, TRAIL, IFN-γ, IL-12[p70], and TNF-α) predicted the likelihood of recurrence with 85.5% accuracy (95% confidence interval 77.9–93.1%).” This cytokine panel and nomogram have potential for identifying patients at risk of tumor recurrence during BCG treatment to guide modification of the dose and duration of BCG immunotherapy. TRIAL REGISTRATION Clinicaltrials.gov NCT01007058.

Ponatinib as first-line treatment for patients with chronic myeloid leukaemia in chronic phase: a phase 2 study

BACKGROUND Ponatinib has shown efficacy in patients with refractory chronic myeloid leukaemia (CML) and in those with CML with a Thr315Ile mutation. We aimed to investigate the activity and safety of ponatinib as first-line treatment for patients with chronic-phase CML. METHODS We did a single-arm, phase 2 trial at MD Anderson Cancer Center in Houston, TX, USA. Between May 3, 2012, and Sept 24, 2013, we enrolled patients with early (<6 months) chronic-phase CML and treated them with oral ponatinib once a day. Patients enrolled before July 25, 2013, were given a starting dose of 45 mg per day; we lowered this due to tolerability issues and patients enrolled after this date were given a starting dose of 30 mg per day. After a warning by the US Food and Drug Administration (FDA) in Oct 6, 2013, for vascular complications with ponatinib, we started all patients on aspirin 81 mg daily and reduced the dose of ponatinib to 30 mg or 15 mg per day for all patients. The primary endpoint was the proportion of patients who achieved complete cytogenetic response by 6 months in the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT01570868. FINDINGS We enrolled 51 patients. Median follow-up was 20·9 months (IQR 14·9–25·2). 43 patients were started on 45 mg ponatinib every day; eight patients were started on 30 mg per day. 43 (94%) of 46 evaluable patients achieved complete cytogenetic response at 6 months. Most frequent toxicities included skin-related effects (n=35; 69%) and elevated lipase (n=32; 63%). Cardiovascular events (mainly hypertension) occurred in 25 (49%) patients. Grade 3–4 myelosuppression occurred in 15 (29%) patients. Five (10%) patients developed cerebrovascular or vaso-occlusive disease. 43 (85%) patients needed treatment interruptions at some time and 45 (88%) needed dose reductions. The study was terminated June 18, 2014, at the recommendation of the FDA due to concern about the increased risk of thromboembolism with ponatinib. INTERPRETATION Patients with newly diagnosed CML in chronic phase respond well to treatment with ponatinib, with most achieving a complete cytogenetic response. Dose adjustment, extensive monitoring, and counselling of the patients for thromboembolic events is needed for patients on ponatinib therapy. However, due to the risk of vascular thrombotic events and the availability of alternative options for these patients, other drugs should be considered first in the frontline setting. FUNDING MD Anderson Cancer Center, National Cancer Institute, ARIAD Pharmaceutical.

Marginal zone lymphomas: Factors that affect the final outcome

A retrospective review and analysis of 275 patients with marginal zone lymphoma (MZL) was performed to determine prognostic factors. An effort was also made to establish a specific prognostic score for patients with extranodal MZL.

Impact of BCR-ABL transcript type on outcome in patients with chronic-phase CML treated with tyrosine kinase inhibitors.

The most common breakpoint cluster region gene-Abelson murine leukemia viral oncogene homolog 1 (BCR-ABL) transcripts in chronic myeloid leukemia (CML) are e13a2 (b2a2) and e14a2 (b3a2). The impact of the type of transcript on response and survival after initial treatment with different tyrosine kinase inhibitors is unknown. This study involved 481 patients with chronic phase CML expressing various BCR-ABL transcripts. Two hundred patients expressed e13a2 (42%), 196 (41%) expressed e14a2, and 85 (18%) expressed both transcripts. The proportion of patients with e13a2, e14a2, and both achieving complete cytogenetic response at 3 and 6 months was 59%, 67%, and 63% and 73%, 81%, and 82%, respectively, whereas major molecular response rates were 27%, 49%, and 50% at 3 months, 42%, 67%, and 70% at 6 months, and 55%, 83%, and 76% at 12 months, respectively. Median (international scale) levels of transcripts e13a2, e14a2, and both at 3 months were 0.2004, 0.056, and 0.0612 and at 6 months were 0.091, 0.0109, and 0.0130, respectively. In multivariate analysis, e14a2 and both predicted for optimal responses at 3, 6, and 12 months. The type of transcript also predicted for improved probability of event-free (P = .043; e14a2) and transformation-free survival (P = .04 for both). Compared to e13a2 transcripts, patients with e14a2 (alone or with coexpressed e13a2) achieved earlier and deeper responses, predicted for optimal European Leukemia Net (ELN) responses (at 3, 6, and 12 months) and predicted for longer event-free and transformation-free survival.

Long-term molecular and cytogenetic response and survival outcomes with imatinib 400 mg, imatinib 800 mg, dasatinib, and nilotinib in patients with chronic-phase chronic myeloid leukaemia: retrospective analysis of patient data from five clinical trials

BACKGROUND Several tyrosine kinase inhibitors (TKIs) are available for treatment of patients with chronic myeloid leukaemia in chronic phase (CML-CP). We analysed long-term molecular and cytogenetic response and survival outcomes for four TKI modalities used as frontline therapy for CML-CP. METHODS In a retrospective cohort analysis, we included data from patients with CML-CP treated in prospective clinical trials with frontline TKI modalities at a single institution between July 31, 2000, and Sept 10, 2013. The main aim of the study was to determine whether achievement of complete cytogenetic response or major molecular response had similar prognostic implications irrespective of the frontline TKI modality used. We analysed each TKI modality for response assessment and analysed survival endpoints (event-free, failure-free, transformation-free, and overall survival) with the Kaplan-Meier method. Univariate and multivariate analyses were done with Cox proportional hazard regression. FINDINGS Our analysis included 482 patients who were treated with imatinib 400 mg daily (n=68), imatinib 800 mg daily (n=200), dasatinib 50 mg twice daily or 100 mg daily (n=106), or nilotinib 400 mg twice daily (n=108). More patients receiving imatinib 800 mg or second-generation TKIs (ie, dasatinib or nilotinib) achieved complete cytogenetic response (58 [87%] of 67 for imatinib 400 mg vs 180 [90%] of 199 for imatinib 800 mg, vs 100 [96%] of 104 for dasatinib vs 99 [93%] of 107 for nilotinib), major molecular response (51 [76%] vs 171 [86%] vs 93 [90%] vs 97 [91%]), and 4·5 log or higher reduction in BCR-ABL transcripts (MR(4·5) response 38 [57%] vs 148 [74%] vs 76 [71%] vs 76 [71%]). This finding was consistent over time (3-60 months). 5-year event free survival significantly differed between the imatinib 400 mg group and the other TKI groups (imatinib 800 mg p=0·029, dasatinib p=0·003, nilotinib p=0·031). There was no significant difference in 5-year failure-free survival (p=0·32, p=0·075, p=0·332), transformation-free survival (p=0·053, p=0·038, p=0·493), or overall survival (p=0·563, p=0·162, p=0·981). Multivariate analysis showed that therapy with imatinib 800 mg (HR 0·51, 95% CI 0·29-0·88, p=0·016), dasatinib (0·28, 0·12-0·66, p=0·004), or nilotinib (0·42, 0·20-0·89, p=0·024) predicted for better event-free survival compared with imatinib 400 mg, but that failure-free, transformation-free, and overall survival were similar irrespective of the TKI used. 28 (41%) patients receiving imatinib 400 mg, 85 (43%) receiving imatinib 800 mg, 23 (21%) receiving dasatinib, and 27 (25%) receiving nilotinib discontinued treatment for any reason. INTERPRETATION Treatment with imatinib 800 mg or the second-generation TKIs dasatinib or nilotinib resulted in superior and deeper responses than did standard-dose imatinib, which were maintained after 5 years of follow-up. Results with imatinib 800 mg were similar to those with second-generation TKIs, although more patients discontinued therapy. FUNDING MD Anderson Cancer Center, National Cancer Institute.

Characteristics and outcomes of patients with multiple myeloma who develop therapy-related myelodysplastic syndrome, chronic myelomonocytic leukemia, or acute myeloid leukemia

BACKGROUND Patients with multiple myeloma (MM) have had significant improvements in outcomes. An increased risk of therapy-related myeloid neoplasms (t-MNs) has also developed. Little is known about the characteristics and outcomes of these patients. PATIENTS AND METHODS Patients with MM treated at our institution from 1993 to 2011 were reviewed. Forty-seven patients were diagnosed with t-MN. Our primary objective was to evaluate the interval to t-MN, response to treatment, and overall survival (OS). RESULTS The median patient age at the MM diagnosis was 65 years. Of the 47 patients, 32 (68.0%) initially received conventional chemotherapeutic agents, 7 (14.9%), novel agents (eg, lenalidomide, thalidomide, bortezomib), and 8 (17.0%), a combination. Twenty patients (42.6%) underwent high-dose chemotherapy and autologous hematopoietic stem cell transplantation. The median interval from the MM diagnosis to t-MN was 7 years (95% CI, 5.0-28.0). Of the 47 patients, 33 (70.2%) developed therapy-related myelodysplastic syndrome (t-MDS), 11 (23.4%) acute myeloid leukemia (t-AML), and 3 (6.4%) chronic myelomonocytic leukemia (t-CMML). The median age at the t-MN diagnosis was 65 years. Of the 47 patients, 26 (78.8%) with t-MDS, 9 (81.8%) with t-AML, and 1 (33.3%) with t-CMML had complex/high-risk cytogenetics. The median OS for all 47 patients after the t-MN diagnosis was 6.3 months (95% CI, 4.0-8.7). CONCLUSION The development of t-MN in patients with MM is associated with poor outcomes. These patients, in general, have complex cytogenetic abnormalities and short complete remission and OS times. A better understanding of the disease biology and novel therapeutic approaches are warranted.

Antileukemia efficacy and mechanisms of action of SL-101, a novel anti-CD123 antibody conjugate, in acute myeloid leukemia

Purpose: The persistence of leukemia stem cells (LSC)-containing cells after induction therapy may contribute to minimal residual disease (MRD) and relapse in acute myeloid leukemia (AML). We investigated the clinical relevance of CD34+CD123+ LSC-containing cells and antileukemia potency of a novel antibody conjugate SL-101 in targeting CD123+ LSCs. Experimental Methods and Results: In a retrospective study on 86 newly diagnosed AML patients, we demonstrated that a higher proportion of CD34+CD123+ LSC-containing cells in remission was associated with persistent MRD and predicted shorter relapse-free survival in patients with poor-risk cytogenetics. Using flow cytometry, we explored the potential benefit of therapeutic targeting of CD34+CD38−CD123+ cells by SL-101, a novel antibody conjugate comprising an anti-CD123 single-chain Fv fused to Pseudomonas exotoxin A. The antileukemia potency of SL-101 was determined by the expression levels of CD123 antigen in a panel of AML cell lines. Colony-forming assay established that SL-101 strongly and selectively suppressed the function of leukemic progenitors while sparing normal counterparts. The internalization, protein synthesis inhibition, and flow cytometry assays revealed the mechanisms underlying the cytotoxic activities of SL-101 involved rapid and efficient internalization of antibody, sustained inhibition of protein synthesis, induction of apoptosis, and blockade of IL3-induced p-STAT5 and p-AKT signaling pathways. In a patient-derived xenograft model using NSG mice, the repopulating capacity of LSCs pretreated with SL-101 in vitro was significantly impaired. Conclusions: Our data define the mechanisms by which SL-101 targets AML and warrant further investigation of the clinical application of SL-101 and other CD123-targeting strategies in AML. Clin Cancer Res; 23(13); 3385–95. ©2017 AACR.

The absolute percent deviation of IGHV mutation rather than a 98% cut‐off predicts survival of chronic lymphocytic leukaemia patients treated with fludarabine, cyclophosphamide and rituximab

The degree of somatic hypermutation, determined as percent deviation of immunoglobulin heavy chain gene variable region sequence from the germline (IGHV%), is an important prognostic factor in chronic lymphocytic leukaemia (CLL). Currently, a cut‐off of 2% deviation or 98% sequence identity to germline in IGHV sequence is routinely used to dichotomize CLL patients into mutated and unmutated groups. Because dissimilar IGHV% cut‐offs of 1–5% were identified in different studies, we wondered whether no cut‐off should be applied and IGHV% treated as a continuous variable. We analysed the significance of IGHV% in 203 CLL patients enrolled on the original frontline fludarabine, cyclophosphamide and rituximab (FCR) trial with a median of 10 years follow‐up. Using the Cox Proportional Hazard model, IGHV% was identified as a continuous variable that is significantly associated with progression‐free (PFS) and overall survival (OS) (P < 0·001). Furthermore, we validated this finding in 323 patients treated with FCR off‐protocol and in the total cohort (n = 535). Multivariate analysis revealed a continuous trend. Higher IGHV% levels were incrementally associated with favorable PFS and OS in both FCR‐treated cohorts (P < 0·001, both cohorts). Taken together, our data suggest that IGHV% is a continuous variable in CLL patients treated with FCR.