JS1.4 Neurological follow-up of neurotoxicity after CAR T cell therapy in lymphoma patients: A French neurological multi-center survey

BACKGROUND

Chimeric antigen receptor-modified T (CAR T) cell therapy is a highly promising treatment for haematological malignancies but is frequently associated with cytokine-release syndrome (CRS) and neurotoxicity. The physiopathological mechanisms of neurological complications and their links with CRS remain largely unknown. The aims of this study are: a) to follow-up longitudinally patients treated with CAR-T cell therapy; b) to exhaustively identify neurological signs and symptoms and; c) to describe their occurrence over time.

MATERIAL AND METHODS

Since September 2018, all patients treated with CD19-targeted CAR T cell therapy for relapsing lymphoma were systematically followed-up and monitored for signs of neurotoxicity by a neurologist. Five different centres (Paris-Saint-Louis, Nantes, Lyon, Montpellier, and Rennes) participated in this study.

RESULTS

As of April 1st 2019, 57 patients, mean age 49 years (range from 22 to 72 years, median age 50 years), 22 females / 35 males, all treated for lymphoma, were included in this study Neurotoxicity, defined as the presence of at least one neurological sign or symptoms appearing after treatment infusion, was present in 33 % of patients. The median time to onset was 7.5 days after infusion with a median duration of symptoms of 5 days. Neurological symptoms were: Encephalopathy (52%), cerebellar syndrome (26%), aphasia (15%), agraphia (15%), executive syndrome (10%), myoclonus (10%), dysarthria (10%), meningismus (5%), transverse myelitis (5%), seizure (5%), neuralgia (5%), and dysesthesia (5%). The severity grade of neurotoxicity was grade 4: 2 patients, Grade 3: 7 patients, grade 2: 5 patients and grade 1: 5 patients (CTCAE grading). CRS was observed in 75% of patients. All patients who developed neurological disorders also had CRS (grade 1: 68%, grade 2: 10%, grade 3: 15%, grade 4: 5%) that preceded neurotoxicity. As the study is still ongoing, updated results will be presented at the EANO meeting.

CONCLUSION

Neurotoxicity associated with CAR-T therapies occurs in one third of patients. This high frequency underlines the need: 1 - to neurologically assess all patients before and repeatedly after therapy infusions; 2 - to provide guidelines for neurological assessment and relevant investigations to improve early recognition of neurotoxicity and its management

Clinical characteristics and prognostic factors of plasmablastic lymphoma patients: analysis of 135 patients from the LYSA group

Background

Plasmablastic lymphoma (PBL), initially described in 1997 in the oral cavity of HIV positive patients, is now recognized as a distinct aggressive and rare entity of diffuse large B-cells lymphoma by the World Health Organization (WHO) classification. Since the original description, others cases have been reported. However, these are largely derived from case reports or small series limiting any definitive conclusions on clinical characteristics and outcome.

Patients and methods

The clinical, biological, pathological features and outcome of a cohort including 135 patients with PBL, from LYSA centers in France and Belgium, were reported and analyzed.

Results

The median age was 58 years, with a male predominance. The cohort was divided into 56 HIV-positive patients, 17 post-transplant patients and 62 HIV-negative/non-transplanted patients. Within HIV-negative/non-transplanted, a relative immunosuppression was found in most cases (systemic inflammatory disease, history of cancer, increased age associated with weakened immune system). We have also described a new subtype, PBL arising in a chronic localized inflammatory site, without any sign of immunosuppression. At presentation, 19% of patients showed oral involvement. Immunophenotype showed CD138 positivity in 88% of cases and CD20 negativity in 90% of cases. Chemotherapy was administered to 80% of patients, with a complete response (CR) rate of 55%. The median overall survival (OS) was 32 months. In univariate analysis, HIV positive status showed better OS when compared with HIV negative status. In multivariate analysis, International Prognostic Index score, chemotherapy and CR were associated with survival benefit.

Conclusion(s)

This cohort, the largest reported to date, increases the spectrum of knowledge on PBL, rarely described. However, specific guidelines to clarify treatment are lacking, and may improve the poor prognosis of this rare disease.

[Kinetic and organization of granulocytes transfusion: a case report]

BACKGROUND

Therapeutic granulocyte transfusion remains an indication for neutropenic sepsis associated with prolonged neutropenia. However, harvest complexity and lack of proved efficacy mark the limits of its development.

CASE REPORT

A 58-year old man received allogeneic stem cell transplantation for osteomyelofibrosis. Six months later, after a transplant rejection, he presented with perineal cellulitis from hemorrhoid origin, without any microbiological documentation. The evolution was unfavorable despite antibiotic and antifungal therapy. A set of seven granulocytes transfusions was initiated. Re-circulation of granulocytes analysis showed an initial increase (H2) followed by a decrease (H8) reaching the basal rate at H16. No toxicity has been reported during or following the transfusions. Clinical improvement has been reported five days after the first transfusion, scaring over at D15, without any neutrophil recovery.

CONCLUSION

In 2014, granulocyte transfusion therapy is indicated for severe infection associated with long-term neutropenia. Minimal circulation of transfused cells in our observation and fast clinical improvement suggest the concentration of granulocytes on the infected area.

A phase II study of enzastaurin, a protein kinase C beta inhibitor, in patients with relapsed or refractory mantle cell lymphoma

BACKGROUND

Protein kinase C beta (PKCbeta), a pivotal enzyme in B-cell signaling and survival, is overexpressed in most cases of mantle cell lymphoma (MCL). Activation of PI3K/AKT pathway is involved in pathogenesis of MCL. Enzastaurin, an oral serine/threonine kinase inhibitor, suppresses signaling through PKCbeta/PI3K/AKT pathways, induces apoptosis, reduces proliferation, and suppresses tumor-induced angiogenesis.

PATIENTS AND METHODS

Patients with relapsed/refractory MCL, and no more than four regimens of prior therapy, received 500 mg enzastaurin, orally, once daily.

RESULTS

Sixty patients, median age 66 years (range 45-85), Eastern Cooperative Oncology Group performance status of zero to two (48% had baseline International Prognostic Index of 3-5), were enrolled. Most patients had prior CHOP-like chemotherapy and/or rituximab (median = 2 regimens). No drug-related deaths occurred. There was one case each of grade 3 anemia, diarrhea, dyspnea, vomiting, hypotension, and syncope. Fatigue was the most common toxicity. Although no objective tumor responses occurred, 22 patients (37%, 95% CI 25% to 49%) were free from progression (FFP) for > or =3 cycles (one cycle = 28 days); 6 of 22 were FFP for >6 months. Two patients remain on treatment and FFP at >23 months.

CONCLUSION

Freedom from progression for >6 months in six patients and a favorable toxicity profile with minimal hematological toxicity indicate that enzastaurin warrants evaluation as maintenance therapy and combination chemotherapy in MCL.

Evaluation of a peptide ELISA for the detection of rituximab in serum

Pharmacokinetic studies of therapeutic monoclonal antibodies necessitate the measurement of their biologically active fraction. The aim of this work was to develop an enzyme-linked immunosorbent assay (ELISA) for rituximab, a chimeric anti-CD20 monoclonal antibody, based on its binding to a 20-mer peptide (P20) derived from the extracellular loop of human CD20 (residues 165-184). Derivatives of P20 were prepared by conjugation to bovine serum albumin (BSA-P20ACM) or biotin (Biot-P20ACM). Interactions of P20 and its derived peptides with rituximab were analyzed by surface plasmon resonance (SPR) and by ELISA. A monoclonal anti-idiotype antibody (MB2A4) was used as the reference in each case. SPR analysis showed that P20 (conjugated or unconjugated) had a lower affinity for rituximab than MB2A4. ELISA methods based on P20 or MB2A4 were both highly accurate and reproducible for rituximab measurement in spiked samples, but the MB2A4-based assay had a lower limit of quantification. Interestingly, discrepant results were obtained with the two ELISA methods when analyzing pharmacokinetic samples, with the rituximab concentrations obtained with the MB2A4-based method being systematically higher than those determined by the P20-based method. Possible interference of circulating CD20 with the P20-based method was supported by competition experiments. Rituximab aggregation in the bloodstream may also account for the bias observed in samples from healthy mice. The P20-based ELISA is far less sensitive than the MB2A-based ELISA, thus limiting its utility for pharmacokinetic studies. However, the discrepancy observed between two different approaches for rituximab measurement indicates that data from different studies should be interpreted with care.