Anti-CD19 CAR T-Cell Therapy for B-Cell Non-Hodgkin Lymphoma

CAR T-cells are autologous T-cells transduced with a chimeric antigen receptor which targets the modified T-cell against a specified cancer antigen. Anti-CD19 CAR T-cells currently represent transformational therapy for relapsed/refractory aggressive B-cell lymphomas where durable remissions can be induced in patients with previously incurable chemotherapy-refractory disease. Three anti-CD19 CAR T-cells are currently Food and Drug Administration and European Medicines Agency approved or in advanced-stage development: axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel. Although all targeting CD19 on the surface of malignant (and healthy) B-cells, these products differ from one another in multiple ways including construct, manufacturing, dose, design of pivotal clinical trials, and toxicity profile. Efficacy and safety data for anti-CD19 CAR T-cell therapy in aggressive B-cell lymphomas will be reviewed, as well as novel CAR T-cell designs and strategies for overcoming treatment resistance.

Ibrutinib plus fludarabine, cyclophosphamide, and rituximab as initial treatment for younger patients with chronic lymphocytic leukaemia: a single-arm, multicentre, phase 2 trial

BACKGROUND

Fludarabine, cyclophosphamide, and rituximab (FCR) can improve disease-free survival for younger (age ≤65 years) fit patients with chronic lymphocytic leukaemia with mutated IGHV. However, patients with unmutated IGHV rarely have durable responses. Ibrutinib is active for patients with chronic lymphocytic leukaemia irrespective of IGHV mutation status but requires continuous treatment. We postulated that time-limited ibrutinib plus FCR would induce durable responses in younger fit patients with chronic lymphocytic leukaemia.

METHODS

We did a multicentre, open-label, non-randomised, single-arm phase 2 trial at seven sites in the USA. We enrolled patients aged 65 years or younger with previously untreated chronic lymphocytic leukaemia. Our initial cohort (original cohort) was not restricted by prognostic marker status and included patients who had del(17p) or TP53 aberrations. After a protocol amendment (on March 21, 2017), we enrolled an additional cohort (expansion cohort) that included patients without del(17p). Ibrutinib was given orally (420 mg/day) for 7 days, then up to six 28-day cycles were administered intravenously of fludarabine (25 mg/m2, days 1-3), cyclophosphamide (250 mg/m2, days 1-3), and rituximab (375 mg/m2 day 1 of cycle 1; 500 mg/m2 day 1 of cycles 2-6) with continuous oral ibrutinib (420 mg/day). Responders continued on ibrutinib maintenance for up to 2 years, and patients with undetectable minimal residual disease in bone marrow after 2 years were able to discontinue treatment. The primary endpoint was the proportion of patients who achieved a complete response with undetectable minimal residual disease in bone marrow 2 months after the last cycle of ibrutinib plus FCR. Analyses were done per-protocol in all patients who received at least one dose of study treatment. This trial is registered with ClinicalTrials.gov (NCT02251548) and is ongoing.

FINDINGS

Between Oct 23, 2014, and April 23, 2018, 85 patients with chronic lymphocytic leukaemia were enrolled. del(17p) was detected in four (5%) of 83 patients and TP53 mutations were noted in three (4%) of 81 patients; two patients had both del(17p) and TP53 mutations. Median patients' age was 55 years (IQR 50-58). At data cutoff, median follow-up was 16·5 months (IQR 10·6-34·1). A complete response and undetectable minimal residual disease in bone marrow 2 months after the last cycle of ibrutinib plus FCR was achieved by 28 (33%, 95% CI 0·23-0·44) of 85 patients (p=0·0035 compared with a 20% historical value with FCR alone). A best response of undetectable minimal residual disease in bone marrow was achieved by 71 (84%) of 85 patients during the study. One patient had disease progression and one patient died (sudden cardiac death after 17 months of ibrutinib maintenance, assessed as possibly related to ibrutinib). The most common all-grade toxic effects were haematological, including thrombocytopenia in 63 (74%) patients, neutropenia in 53 (62%), and anaemia in 41 (49%). Grade 3 or 4 non-haematological serious adverse events included grade 3 atrial fibrillation in three (4%) patients and grade 3 Pneumocystis jirovecii pneumonia in two (2%).

INTERPRETATION

The proportion of patients who achieved undetectable minimal residual disease in bone marrow with ibrutinib plus FCR is, to our knowledge, the highest ever published in patients with chronic lymphocytic leukaemia unrestricted by prognostic marker status. Ibrutinib plus FCR is promising as a time-limited combination regimen for frontline chronic lymphocytic leukaemia treatment in younger fit patients.

FUNDING

Pharmacyclics and the Leukemia & Lymphoma Society.

Hitting back at lymphoma: How do modern diagnostics identify high-risk diffuse large B-cell lymphoma subsets and alter treatment?

Diffuse large B-cell lymphoma (DLBCL) is a clinically and biologically heterogeneous disease. Diagnostic tools in the clinic can now identify distinct subsets characterized by unique molecular features, which are increasingly transforming how these patients are managed. Activated B-cell-like DLBCL is characterized by NF-κB activation and chronic B-cell receptor signaling and may be targeted with lenalidomide or ibrutinib in the relapsed setting. Germinal center-like DLBCL is enriched for activating EZH2 mutations, and encouraging activity has been observed for the EZH2 inhibitor tazemetostat, which now has a fast-track US Food and Drug Administration designation. Double-hit lymphoma is a high-grade B-cell lymphoma characterized by translocations of MYC and BCL2 and/or BCL6 and carries a poor prognosis. Intensive chemoimmunotherapy strategies appear to be superior to standard R-CHOP (rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone) as initial therapy, and anti-CD19 chimeric antigen receptor T cells are inducing remission in patients with relapsed/refractory disease who previously had few available options. Primary mediastinal (thymic) large B-cell lymphoma is a molecularly distinct large-cell lymphoma with clinical and molecular features that overlap with those of classical Hodgkin lymphoma. R-CHOP has been associated with an unacceptably high rate of primary treatment failure in this young population, whereas dose-adjusted EPOCH-R (etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin plus rituximab) produces durable remissions without the need for radiotherapy in most patients. For relapsed/refractory disease, immune checkpoint inhibitors targeting PD-1 have shown promising activity in chemotherapy-refractory disease, as have anti-CD19 chimeric antigen receptor T cells. Additional therapeutic targets, including JAK2, continue to be evaluated. The identification of discrete biological subsets is steadily moving us away from a "one-size-fits-all" approach in DLBCL.

Ibrutinib maintenance following induction for untreated mantle cell lymphoma (MCL): Initial safety report

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Background: Maintenance rituximab in MCL has improved survival, though the optimal approach is not yet defined. Ibrutinib, a selective BTK inhibitor, has profound activity in R/R MCL. Ibrutinib maintenance (I-M) following induction for treatment-naive MCL has not been explored. We report preliminary results of a multicenter phase II trial assessing efficacy and safety of I-M for MCL after frontline induction. Methods: Patients with MCL with CR/PR to frontline chemo-immunotherapy (+/- autoSCT) received I-M 560 mg daily for up to 4 years. Primary objective was 3 year PFS rate. Secondary objectives were PR to CR conversions, median OS at 4 years and toxicity with MRD assessments planned. Results: Accrual is complete with 36 patients, median age of 60 (range 46-90), 28 males, 28 with advanced stage and 9 with extranodal disease. 18 (50%), 7 (19%) and 11 (31%) had low vs intermediate vs high risk MIPI respectively. 8/24 patients had a Ki-67 > / = 30%. For induction, 17 (47%) received BR, 18 (50%) a cytarabine-based regimen, 1 (3%) R-CHOP. 18 (50%) had autoSCT in CR1 prior to enrollment. 33 (92%) and 3 (8%) had CR and PR with induction respectively with 1 PR to CR conversion on I-M. At median follow-up of 19 mos, 24/36 (67%) patients remain on I-M (median 15 cycles, range 1-49) with 1 PD and 1 death. TRAEs led to dose reductions/interruptions in 25 (69%) patients, including permanent dose reductions in 7 (19%) and treatment discontinuation in 9 (25%; Table). 3 additional patients discontinued I-M, 1 for endometrial adenocarcinoma, 1 PD, 1 death, cause unknown. Conclusions: Ibrutinib maintenance is feasible in MCL patients who respond to frontline chemo-immunotherapy +/- autoSCT with manageable toxicities consistent with prior reports of ibrutinib. Additional follow-up and MRD status correlations with PFS and OS will provide insight on clinical relevance for this approach. Clinical trial information: NCT02242097. [Table: see text]

Lisocabtagene maraleucel (liso-cel) treatment of patients (pts) with relapsed/refractory (R/R) B-cell non-Hodgkin lymphoma (NHL) and secondary CNS lymphoma: Initial results from TRANSCEND NHL 001

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Background: No clinical studies have yet evaluated CAR T cell therapies in pts with R/R B-cell NHL who have secondary CNS lymphoma. We report data from this pt subgroup receiving liso-cel (JCAR017), an investigational, anti-CD19 CAR T cell product administered as a defined composition of CD4+/CD8+ CAR T cells, in the phase 1 TRANSCEND NHL 001 study. Methods: Eligible pts had confirmed B-cell NHL with R/R disease after ≥2 prior lines of therapy. Pts with secondary CNS lymphoma could enroll or, if it developed on study, could continue to receive liso-cel. After lymphodepleting chemotherapy, liso-cel was administered at 1 of 2 dose levels (DL): DL1 = 50 × 106 or DL2 = 100 × 106 total CAR+ T cells. Efficacy was evaluated per the Lugano criteria. Pts achieving a complete response could be retreated with liso-cel upon progressive disease. Results: At data cutoff, 9 pts with secondary CNS lymphoma at initial treatment (n = 6), retreatment (n = 2), or cycle 2 (n = 1) received liso-cel. 4 pts were treated at DL1 and 5 at DL2. The median (range) age was 60 (47‒73) years and number of prior lines of therapy was 3 (2‒7). Median time to peak CAR+ T cell expansion was 12.5 (7–112) days. 1 of 9 pts had grade (G)2 cytokine release syndrome (CRS) and 1 of 9 pts had a neurological event (NE; G3 decreased level of consciousness). No retreatment pts had CRS or NE; however, 1 retreatment pt had an NE of G2 temporal edema with initial treatment with liso-cel. 5 pts received prophylactic levetiracetam. 1 pt received corticosteroids and tocilizumab. Other toxicities were predominantly cytopenias. There were no treatment-related deaths. 4 pts responded to liso-cel; all had a best response of complete response, of which 2 are ongoing at 270 and 545 days post-liso-cel. All 4 responses occurred after initial liso-cel treatment; no retreated pts responded. Conclusions: In the ongoing TRANSCEND NHL 001 study, liso-cel continues to demonstrate the ability to be safely delivered to pts with R/R B-cell NHL, including those with secondary CNS lymphoma, a population of pts with a highly unmet medical need. No excess NE was noted in this population. This cohort continues to be evaluated. Clinical trial information: NCT02631044.

Safety and preliminary efficacy in patients (pts) with relapsed/refractory (R/R) mantle cell lymphoma (MCL) receiving lisocabtagene maraleucel (Liso-cel) in TRANSCEND NHL 001

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Background: Most pts with MCL relapse after first-line immunochemotherapy, with poor responses to salvage therapy. We report initial dose-finding results from pts with R/R MCL treated with liso-cel (JCAR017), an investigational, anti-CD19 CAR T cell product administered as a defined composition of CD4+/CD8+ CAR T cells, in the ongoing phase 1 TRANSCEND study. Methods: Eligible pts had confirmed MCL (cyclin D1 expression, t[11;14]) with R/R disease after ≥1 prior lines of therapy. After lymphodepleting chemotherapy, liso-cel was administered at 1 of 2 dose levels (DL): DL1 = 50 × 106 or DL2 = 100 × 106 total CAR+ T cells. Results: At data cutoff, 9 pts (DL1, n = 6; DL2, n = 3) had received liso-cel. The median (range) age was 66 (58‒78) years; 7 pts were male. Histologies included blastoid (n = 3) and pleiomorphic (n = 1) variants. 8 pts had documented Ki67 > 30% (40%‒80%); 1 pt had TP53 mutation. Pts had received a median of 5 (3‒7) prior therapies; 3 pts had received prior hematopoietic stem cell transplant. All 9 pts had prior ibrutinib; 4 had a best response of progressive disease on ibrutinib. 6/9 pts (67%) received bridging chemotherapy. 4/9 pts (44%) had serious treatment-emergent adverse events (TEAEs). 5/9 pts (56%) had grade (G) 3/4 TEAEs, primarily anemia, neutropenia, and hypophosphatemia (22% each). 3/9 pts (33%) had cytokine release syndrome (CRS); all were G1. Median time to CRS onset was 6 (2‒7) days; median time to resolution was 6 (2‒6) days. 1 pt received tocilizumab and corticosteroids. There were no neurological events. 4 pts died, all in DL1 (3 from disease progression; 1 after receiving new anticancer therapy post liso-cel). Overall response rate was 78% (7/9 pts; 4/6 in DL1, median follow-up 12.4 [95% CI: 9.2–12.4] mo; 3/3 in DL2, median follow-up 1.4 [95% CI: 1.0–1.4] mo). 2 pts in DL1 maintained a durable CR until last follow-up (day 281 and 378, respectively). Median time to peak CAR+ T cell expansion: 9.5 (9–10) days at DL1 and 17.5 (10–27) days at DL2. Conclusions: In this phase 1 study in pts with R/R MCL, liso-cel treatment showed tolerable toxicity and had clinical activity. Updated DL2 data and longer follow-up will be presented. Clinical trial information: NCT02631044.

Burden of cytokine release syndrome (CRS) and neurologic events (NE) in patients (Pts) with relapsed/refractory non-Hodgkin lymphoma (NHL) receiving lisocabtagene maraleucel (Liso-cel; JCAR017) in TRANSCEND NHL 001

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Background: We assessed incidence, healthcare resource utilization (HCRU), and costs of CRS and NE in pts in TRANSCEND receiving liso-cel, an investigational, anti-CD19 CAR T cell product administered as a defined composition of CD4+/CD8+ CAR T cells. Methods: HCRU within the dates of onset and resolution of CRS and NE was identified from case report forms and trial management guidelines. Costs associated with grade (G) of CRS or NE were applied using public databases and literature on national average costs from a provider perspective. Results: Of 102 pts, 21 (21%) had CRS only (no G≥3), 6 (6%) had NE only (no G≥4), 6 (6%) had nonconcurrent CRS and NE, and 11 (11%) had concurrent CRS and NE (including 1 G4 CRS). Most pts had G≤2 events (31/44, 70%). Of pts with both CRS and NE, 16/17 (94%) had CRS first. Of pts with nonconcurrent events, NE developed a median of 2 days after CRS resolved. Of 10/11 pts with concurrent events and CRS before NE, NE developed a median of 3.5 days after CRS onset. 11/38 pts with CRS (29%) received tocilizumab and 21/44 with CRS and/or NE (48%) received dexamethasone. Overall median costs for G≤2 vs G≥3 CRS and/or NE were $16,479 vs $70,549. Management costs for CRS and/or NE were largely driven by hospitalizations (Table), and ranged $177–24,947 for G≤2 CRS or NE only, $30,749 for G≤2 concurrent CRS and NE, and $43,974–264,149 for G≥3 CRS and/or NE. Conclusions: In TRANSCEND, incidences of G≥3 CRS and NE were low. G≥3 events resulted in a 328% increase in overall median costs vs G≤2 events. Clinical trial information: NCT02631044. [Table: see text]

Chimeric Antigen Receptor T-Cell Therapies for Aggressive B-Cell Lymphomas: Current and Future State of the Art

Aggressive B-cell lymphomas that are primary refractory to, or relapse after, frontline chemoimmunotherapy have a low cure rate with conventional therapies. Although high-dose chemotherapy remains the standard of care at first relapse for sufficiently young and fit patients, fewer than one-quarter of patients with relapsed/refractory disease are cured with this approach. Anti-CD19 chimeric antigen receptor (CAR) T cells have emerged as an effective therapy in patients with multiple relapsed/refractory disease, capable of inducing durable remissions in patients with chemotherapy-refractory disease. Three anti-CD19 CAR T cells for aggressive B-cell lymphoma (axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene ciloleucel) are either U.S. Food and Drug Administration approved or in late-stage development. All three CAR T cells produce durable remissions in 33%-40% of treated patients. Differences among these products include the specific CAR constructs, costimulatory domains, manufacturing process, dose, and eligibility criteria for their pivotal trials. Notable toxicities include cytokine release syndrome and neurologic toxicities, which are usually treatable and reversible, as well as cytopenias and hypogammaglobulinemia. Incidences of cytokine release syndrome and neurotoxicity differ across CAR T-cell products, related in part to the type of costimulatory domain. Potential mechanisms of resistance include CAR T-cell exhaustion and immune evasion, CD19 antigen loss, and a lack of persistence. Rational combination strategies with CAR T cells are under evaluation, including immune checkpoint inhibitors, immunomodulators, and tyrosine kinase inhibitors. Novel cell products are also being developed and include CAR T cells that target multiple tumor antigens, cytokine-secreting CAR T cells, and gene-edited CAR T cells, among others.

Dose-Adjusted EPOCH-R Compared With R-CHOP as Frontline Therapy for Diffuse Large B-Cell Lymphoma: Clinical Outcomes of the Phase III Intergroup Trial Alliance/CALGB 50303

PURPOSE

Alliance/CALGB 50303 (NCT00118209), an intergroup, phase III study, compared dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, doxorubicin, and rituximab (DA-EPOCH-R) with standard rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) as frontline therapy for diffuse large B-cell lymphoma.

PATIENTS AND METHODS

Patients received six cycles of DA-EPOCH-R or R-CHOP. The primary objective was progression-free survival (PFS); secondary clinical objectives included response rate, overall survival (OS), and safety.

RESULTS

Between 2005 and 2013, 524 patients were registered; 491 eligible patients were included in the final analysis. Most patients (74%) had stage III or IV disease; International Prognostic Index (IPI) risk groups included 26% IPI 0 to 1, 37% IPI 2, 25% IPI 3, and 12% IPI 4 to 5. At a median follow-up of 5 years, PFS was not statistically different between the arms (hazard ratio, 0.93; 95% CI, 0.68 to 1.27; P = .65), with a 2-year PFS rate of 78.9% (95% CI, 73.8% to 84.2%) for DA-EPOCH-R and 75.5% (95% CI, 70.2% to 81.1%) for R-CHOP. OS was not different (hazard ratio, 1.09; 95% CI, 0.75 to 1.59; P = .64), with a 2-year OS rate of 86.5% (95% CI, 82.3% to 91%) for DA-EPOCH-R and 85.7% (95% CI, 81.4% to 90.2%) for R-CHOP. Grade 3 and 4 adverse events were more common (P < .001) in the DA-EPOCH-R arm than the R-CHOP arm, including infection (16.9% v 10.7%, respectively), febrile neutropenia (35.0% v 17.7%, respectively), mucositis (8.4% v 2.1%, respectively), and neuropathy (18.6% v 3.3%, respectively). Five treatment-related deaths (2.1%) occurred in each arm.

CONCLUSION

In the 50303 study population, the more intensive, infusional DA-EPOCH-R was more toxic and did not improve PFS or OS compared with R-CHOP. The more favorable results with R-CHOP compared with historical controls suggest a potential patient selection bias and may preclude generalizability of results to specific risk subgroups.

Genome-wide discovery of somatic coding and noncoding mutations in pediatric endemic and sporadic Burkitt lymphoma

Although generally curable with intensive chemotherapy in resource-rich settings, Burkitt lymphoma (BL) remains a deadly disease in older patients and in sub-Saharan Africa. Epstein-Barr virus (EBV) positivity is a feature in more than 90% of cases in malaria-endemic regions, and up to 30% elsewhere. However, the molecular features of BL have not been comprehensively evaluated when taking into account tumor EBV status or geographic origin. Through an integrative analysis of whole-genome and transcriptome data, we show a striking genome-wide increase in aberrant somatic hypermutation in EBV-positive tumors, supporting a link between EBV and activation-induced cytidine deaminase (AICDA) activity. In addition to identifying novel candidate BL genes such as SIN3A, USP7, and CHD8, we demonstrate that EBV-positive tumors had significantly fewer driver mutations, especially among genes with roles in apoptosis. We also found immunoglobulin variable region genes that were disproportionally used to encode clonal B-cell receptors (BCRs) in the tumors. These include IGHV4-34, known to produce autoreactive antibodies, and IGKV3-20, a feature described in other B-cell malignancies but not yet in BL. Our results suggest that tumor EBV status defines a specific BL phenotype irrespective of geographic origin, with particular molecular properties and distinct pathogenic mechanisms. The novel mutation patterns identified here imply rational use of DNA-damaging chemotherapy in some patients with BL and targeted agents such as the CDK4/6 inhibitor palbociclib in others, whereas the importance of BCR signaling in BL strengthens the potential benefit of inhibitors for PI3K, Syk, and Src family kinases among these patients.

Ibrutinib Regimens versus Chemoimmunotherapy in Older Patients with Untreated CLL

BACKGROUND

Ibrutinib has been approved by the Food and Drug Administration for the treatment of patients with untreated chronic lymphocytic leukemia (CLL) since 2016 but has not been compared with chemoimmunotherapy. We conducted a phase 3 trial to evaluate the efficacy of ibrutinib, either alone or in combination with rituximab, relative to chemoimmunotherapy.

METHODS

Patients 65 years of age or older who had untreated CLL were randomly assigned to receive bendamustine plus rituximab, ibrutinib, or ibrutinib plus rituximab. The primary end point was progression-free survival. The Alliance Data and Safety Monitoring Board made the decision to release the data after the protocol-specified efficacy threshold had been met.

RESULTS

A total of 183 patients were assigned to receive bendamustine plus rituximab, 182 to receive ibrutinib, and 182 to receive ibrutinib plus rituximab. Median progression-free survival was reached only with bendamustine plus rituximab. The estimated percentage of patients with progression-free survival at 2 years was 74% with bendamustine plus rituximab and was higher with ibrutinib alone (87%; hazard ratio for disease progression or death, 0.39; 95% confidence interval [CI], 0.26 to 0.58; P<0.001) and with ibrutinib plus rituximab (88%; hazard ratio, 0.38; 95% CI, 0.25 to 0.59; P<0.001). There was no significant difference between the ibrutinib-plus-rituximab group and the ibrutinib group with regard to progression-free survival (hazard ratio, 1.00; 95% CI, 0.62 to 1.62; P=0.49). With a median follow-up of 38 months, there was no significant difference among the three treatment groups with regard to overall survival. The rate of grade 3, 4, or 5 hematologic adverse events was higher with bendamustine plus rituximab (61%) than with ibrutinib or ibrutinib plus rituximab (41% and 39%, respectively), whereas the rate of grade 3, 4, or 5 nonhematologic adverse events was lower with bendamustine plus rituximab (63%) than with the ibrutinib-containing regimens (74% with each regimen).

CONCLUSIONS

Among older patients with untreated CLL, treatment with ibrutinib was superior to treatment with bendamustine plus rituximab with regard to progression-free survival. There was no significant difference between ibrutinib and ibrutinib plus rituximab with regard to progression-free survival. (Funded by the National Cancer Institute and Pharmacyclics; ClinicalTrials.gov number, NCT01886872 .).

Advances in risk assessment and prophylaxis for central nervous system relapse in diffuse large B-cell lymphoma

Central nervous sytem recurrence of diffuse large B-cell lymphoma is an uncommon but devastating event, making identification of patients at high risk for relapse within the central nervous system essential for clinicians. Modern risk stratification includes both clinical and biological features. A validated clinical risk model employing the five traditional International Prognostic Index risk factors plus renal or adrenal involvement can identify a high-risk patient population with a central nervous system recurrence risk of greater than 10%. Lymphoma involvement of certain discrete extranodal sites such as the testis also confers increased risk, even in stage I disease. Adverse biological risk factors for central nervous system relapse include presence of translocations of MYC, BCL2 and/or BCL6, in so-called double- or triple-hit lymphoma. Immunohistochemically detectable co-expression of MYC and BCL2 in the absence of translocations also portends an increased risk of relapse within the central nervous system, particularly in the setting of the activated B-cell-like subtype of diffuse large B-cell lymphoma. The role, method, and timing of prophylactic therapy remain controversial based on the available data. We review both intrathecal and systemic strategies for prophylaxis in high-risk patients. Our preference is for systemic methotrexate in concert with standard chemoimmunotherapy in the majority of cases. Several novel agents have also demonstrated clinical activity in primary and secondary central nervous system lymphoma and warrant future investigation in the prophylactic setting.

Design and clinical validation of a point-of-care device for the diagnosis of lymphoma via contrast-enhanced microholography and machine learning

The identification of patients with aggressive cancer who require immediate therapy is a health challenge in low-income and middle-income countries. Limited pathology resources, high healthcare costs and large-case loads call for the development of advanced standalone diagnostics. Here, we report and validate an automated, low-cost point-of-care device for the molecular diagnosis of aggressive lymphomas. The device uses contrast-enhanced microholography and a deep-learning algorithm to directly analyse percutaneously obtained fine-needle aspirates. We show the feasibility and high accuracy of the device in cells, as well as the prospective validation of the results in 40 patients clinically referred for image-guided aspiration of nodal mass lesions suspicious for lymphoma. Automated analysis of human samples with the portable device should allow for the accurate classification of patients with benign and malignant adenopathy.

Impact of HIV Infection on the Clinical Presentation and Survival of Non-Hodgkin Lymphoma: A Prospective Observational Study From Botswana

PURPOSE

Botswana has a high prevalence of HIV infection. Currently, there are few data regarding the sociodemographic factors, clinical characteristics, and outcomes of non-Hodgkin lymphoma (NHL)-an AIDS-defining cancer-in the country.

PATIENTS AND METHODS

This study used a prospective cancer registry to identify patients with a new diagnosis of NHL reporting for specialty cancer care at three hospitals in Botswana between October 2010 and August 2016. Treatment patterns and clinical outcomes were analyzed.

RESULTS

One hundred four patients with a new diagnosis of NHL were enrolled in this study, 72% of whom had HIV infection. Compared with patients not infected with HIV, patients infected with HIV were younger (median age, 53.9 v 39.1 years; P = .001) and more likely to present with an aggressive subtype of NHL (65.5% v 84.0%; P = .008). All patients infected with HIV received combined antiretroviral therapy throughout the course of the study, and similar chemotherapeutic regimens were recommended for all patients, regardless of subtype or HIV status (six to eight cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone; or cyclophosphamide, doxorubicin, vincristine, and prednisone plus rituximab). There was no difference in 1-year mortality among patients not infected with HIV and patients infected with HIV (unadjusted analysis, 52.9% v 37.1%; hazard ratio [HR], 0.73; P = .33; adjusted analysis, HR, 0.57; P = .14). However, when compared with a cohort of patients in the United States matched by subtype, stage, age, sex, and race, patients in Botswana fared worse (1-year mortality, 22.8% v 46.3%; HR, 1.89; P = .001).

CONCLUSION

Among patients with NHL reporting for specialty cancer care in Botswana, there is no association between HIV status and 1-year survival.

Abstract 3674: Pharmacodynamic assessment in whole blood for the BET bromodomain inhibitor CPI-0610 of target engagement in patients with progressive lymphoma

Defining the relationship between small molecule exposure, clinical efficacy and target engagement via pharmacodynamic (PD) biomarkers is a key element of phase 1 clinical development. CPI-0610 is an orally bioavailable inhibitor of the bromodomain and extra-terminal (BET) domain family of proteins currently being evaluated in a number of phase I trials. To support the clinical development of CPI-0610, we sought to identify BET target genes in whole blood that function as PD markers for target engagement in patients. The utilization of whole blood rather than tumor samples for PD assessments allows for a high level of compliance for sample collection and assessment of serial samples to understand the kinetics of optimal gene regulation. This is important for the mechanism of action of BET bromodomain inhibitors, as it has been shown that target gene suppression is rapidly reversible upon removal of drug. A preliminary list of BET target genes was first identified after ex vivo treatment of healthy donor blood samples with a BET inhibitor followed by transcriptional profiling. Further characterization was carried out using blood samples recovered from in vivo studies in mice, as well as rat and dog toxicology studies for CPI-0610. Blood samples collected from patients with progressive lymphoma participating in a Phase I clinical study (NCT01949883) were analyzed for changes in the BET target genes and correlated with CPI-0610 dose, pharmacokinetic (PK) exposure and clinical activity. This enabled further refinement of the BET target gene signature to identify the most robust gene expression changes in patient samples. IL8 and CCR1 were the most strongly regulated genes, showing an exposure-dependent downregulation in patient samples. Using these target genes, we were able to identify a minimum threshold of exposure required for BET target engagement as well as show that BET target engagement can be achieved at doses below the maximum tolerated dose. Furthermore, ≥50% downregulation of IL8 was consistent with anti-lymphoma activity in patients from our trial. CCR2, FN1, CSF1R and THBS1 were identified and validated preclinically but in patient samples were difficult to interpret due to lack of robust regulation or low basal levels of expression. In summary, a BET target gene signature assay using whole blood samples was established and implemented in a Phase I lymphoma study which demonstrated that CPI-0610 regulates direct BET target genes in blood cells in a robust and dose-dependent manner.

Citation Format: Jennifer A. Mertz, Kristie A. Blum, Anas Younes, Jeremy S. Abramson, Michael B. Maris, Ian W. Flinn, Andre Goy, Darrell R. Borger, Michael R. Cooper, Robert J. Sims. Pharmacodynamic assessment in whole blood for the BET bromodomain inhibitor CPI-0610 of target engagement in patients with progressive lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3674.

Panobinostat in combination with rituximab in heavily pretreated diffuse large B-cell lymphoma: Results of a phase II study

This is a phase II study of panobinostat, an oral pan-HDAC inhibitor, combined with rituximab in patients with relapsed diffuse large B cell lymphoma. Panobinostat was administered orally 3 times a week every other week on a 28-day cycle. Rituximab was administered weekly during the first cycle, then on Day 1 of cycles 2 to 6. Patients without disease progression after 6 cycles continued panobinostat monotherapy for up to 6 additional cycles in the absence of disease progression. Eighteen eligible subjects were enrolled, and 18 were evaluable for response. The overall response rate was 11% (90% CI [2%-34%]) with 2 subjects having a partial response. The duration of response in these subjects was 51 and 60 days. Five additional subjects had stable disease with 3 subjects having tumor reduction between 27 and 44%, not meeting criteria for partial response. One subject with stable disease remained on therapy a total of 12 cycles. The most common toxicities while on study were thrombocytopenia (14 patients, 78%); fatigue (11, 61%); anemia (10, 56%); diarrhea (8, 44%); and nausea, lymphopenia, anorexia, and hypophosphatemia (5 each, 28% of patients), the majority of which was grade 2 or less. These data indicate that the combination of panobinostat with rituximab is able to induce responses in a limited number of subjects with relapsed diffuse large B cell lymphoma.

Correlation of patient characteristics and biomarkers with clinical outcomes of JCAR017 in R/R aggressive B-NHL (TRANSCEND NHL 001 study)

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Background: JCAR017 is a defined composition, CD19-directed 4-1BB CAR T cell product administered at a precise dose of CD8 and CD4 CAR T cells in a seamless design Ph1 pivotal trial of R/R B-cell NHL (TRANSCEND NHL 001; NCT02631044). Methods: Blood samples were collected for biomarker analyses at protocol-defined time points. PK (CAR T cell expansion and persistence) was measured using flow cytometry. Cytokines were measured on a Luminex platform. Additional analytes will be presented. All reported p-values are 2-sided without multiplicity adjustment. Results: Safety (n = 59) and efficacy (n = 54) outcomes were analyzed for correlations with patient (pt) characteristics and biomarkers. Dose level did not correlate with cytokine release syndrome (CRS) or neurotoxicity (NT) despite higher median Cmax and median AUC0-28 at DL2. In pts with NT or ≥Gr 2 CRS, CD4 and CD8 CAR T cell levels were 5-10 fold and 3-5 fold higher, respectively, than median DL2 levels. Pt factors that correlated with any grade CRS and NT were ECOG 2 (p = 0.03) and high disease burden (p < 0.05). Higher levels of IL-8, IL-10, and CXCL10 before CART cell infusion were associated with Gr 3-4 NT (each p< 0.05), suggesting that inherent pt factors may result in higher CAR T expansion and associated CRS and NT. Lower pre-CAR T cell ferritin, LDH, CXCL10, G-CSF, and IL-10 were associated with CR/PR, and lower pre-CAR T cell ferritin, CRP, LDH, CXCL10, IL-8, IL-10, IL-15, MCP-1, MIP-1β, TNF-α were associated with 3-month durable response (each p< 0.05). Median Cmax and AUC0-28 of CD8 CAR T cells were higher in responding patients and with durable response at Month 3 (CD8 Cmax median = 20.8 vs 5.5; CD8 AUC median = 235 vs 55 in CR/PR vs PD at Month 3). Of pts evaluable for persistence at 3 months (n = 29), 90% and 93% had detectable CD8+ and CD4+ CAR+ T cells; of those with available PK results at time of relapse (n = 11), 82% had persistence at time of relapse. Conclusions: JCAR017 demonstrated increased CAR T cell expansion and persistence and higher durability of response at higher dose levels, with manageable toxicities. CAR T cells were also detected at time of relapse, suggesting potential opportunities for future combination clinical trials. Clinical trial information: NCT02631044.

High durable CR rates and preliminary safety profile for JCAR017 in R/R aggressive b-NHL (TRANSCEND NHL 001 Study): A defined composition CD19-directed CAR T-cell product with potential for outpatient administration

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Background: JCAR017 is a defined composition, CD19-directed 4-1BB CAR T cell product administered at a precise dose of CD8 and CD4 CAR T cells in a seamless design Phase 1 pivotal trial of relapsed/refractory (R/R) B-cell NHL (TRANSCEND NHL 001; NCT02631044). Methods: Patients (pts) with R/R DLBCL NOS, PMBCL, FL grade 3B, or MCL and adequate organ function are eligible. The FULL dataset includes all pts in the DLBCL cohort (i.e. excludes MCL). The CORE dataset includes pts meeting inclusion for a planned pivotal DLBCL cohort (DLBCL NOS [ de novo or transformed from follicular lymphoma], ECOG 0-1, no prior allo-SCT). Results: As of July 7, 2017, 69 pts were treated in the DLBCL cohort and evaluable for safety. In the FULL dataset, 21 pts (30%) had cytokine release syndrome (CRS), with 1 serious CRS event (1%; Gr 4). Neurotoxicity (NT) at any grade developed in 14 (20%), including 10 (14%) with Gr 3-4 events. There were no Gr 5 CRS or NT events. Median time to onset of first CRS and NT was 5 days and 10 days, respectively, 13 (19%) received anti-cytokine therapy and only one required vasopressor support. In the CORE dataset (n = 49), similar rates of CRS and NT were shown. The majority of pts, 64% (44/69), had no CRS or NT, and median onset of CRS and NT were 5 and 11 days, respectively, suggesting outpatient delivery of JCAR017 may be feasible. In the DLBCL cohort, 68 pts were evaluable for efficacy; best overall response, 3-month, and 6-month response rates in the FULL dataset were 75% (51/68), 49% (27/55), and 40% (14/35), respectively; and, in the CORE dataset, were 84% (41/49), 65% (26/40), and 57% (13/23). The best overall, 3-month, and 6-month CR rates were 61% (30/49), 53% (21/40), and 52% (12/23), respectively, in the CORE dataset. Among 16 double/triple hit pts, best ORR was 81%, and 3-month CR rate was 60%. A trend toward improved response rate at 3 months was observed in pts treated at DL2 compared to DL1. Conclusions: At the symposium, we will report updated efficacy and the preliminary safety profile for JCAR017, which supports potential outpatient administration in R/R Aggressive B-NHL patients. Clinical trial information: NCT02631044.

NCCN Guidelines Insights: Chronic Lymphocytic Leukemia/Small Lymphocytic Lymphoma, Version 1.2017

Chronic lymphocytic leukemia (CLL) and small lymphocytic lymphoma (SLL) are different manifestations of the same disease and managed in much the same way. The advent of novel CD20 monoclonal antibodies led to the development of effective chemoimmunotherapy regimens. More recently, small molecule inhibitors targeting kinases involved in a number of critical signaling pathways and a small molecule inhibitor of the BCL-2 family of proteins have demonstrated activity for the treatment of patients with CLL/SLL. These NCCN Guidelines Insights highlight important updates to the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for CLL/SLL for the treatment of patients with newly diagnosed or relapsed/refractory CLL/SLL.