French early nationwide idecabtagene vicleucel chimeric antigen receptor T-cell therapy experience in patients with relapsed/refractory multiple myeloma (FENIX): A real-world IFM study from the DESCAR-T registry.

Idecabtagene vicleucel (ide-cel), a chimeric antigen receptor T-cell therapy targeting B-cell maturation antigen (BCMA), received early access program (EAP) authorization in France in April 2021 for relapsed/refractory multiple myeloma (RRMM). We conducted a real-world registry-based multicentre observational study in 11 French hospitals to evaluate ide-cel outcomes. Data from 176 RRMM patients who underwent apheresis between June 2021 and November 2022 were collected from the French national DESCAR-T registry. Of these, 159 patients (90%) received ide-cel. Cytokine release syndrome occurred in 90% with 2% grade ≥3, and neurotoxicity occurred in 12% with 3% grade ≥3. Over the first 6 months, the best overall response and ≥complete response rates were 88% and 47% respectively. The median progression-free survival (PFS) from the ide-cel infusion was 12.5 months, the median overall survival (OS) was 20.8 months and the estimated OS rate at 12 months was 73.3%. Patients with extra-medullary disease (EMD) had impaired PFS (6.2 months vs. 14.8 months). On multivariable analysis, EMD and previous exposure to BCMA-targeted immunoconjugate or T-cell-redirecting GPRC5D bispecific antibody were associated with inferior PFS. Our study supports ide-cel's feasibility, safety and efficacy in real-life settings, emphasizing the importance of screening for EMD and considering prior treatments to optimize patient selection.

[POEMS syndrome: Diagnosis, stratification, treatments]. / Syndrome POEMS : diagnostic, prise en charge et traitements.

POEMS syndrome is a rare form of B-cell dyscrasia with multiple clinical signs including the acronym for polyneuropathy, organomegaly, endocrinopathy, M-protein and skin changes. It is a paraneoplastic syndrome due to an underlying plasma cell disorder belonging to the monoclonal gammopathies of clinical significance (MGCS). The major criteria for this syndrome are polyradiculoneuropathy, clonal plasma cell disorder (PCD), sclerotic bone lesions, elevated vascular endothelial growth factor (VEGF), and the presence of Castleman's disease. Minor features include organomegaly, endocrinopathy, skin changes, papilledema, extravascular volume over-load, and thrombocytosis. The diagnosis of POEMS syndrome requires three of the major criteria, two of which must include polyradiculoneuropathy and clonal PCD, and at least one of the minor criteria. VEGF plays a major role in the disease although anti-VEGF treatments have been disappointing. Risk stratification is based on clinical phenotype rather than specific molecular markers. Depending on bone marrow involvement and the number of sclerotic bone lesions, first line therapy should be irradiation or systemic therapy. For patients with a dominant sclerotic plasmacytoma, first line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement and for those who have progression of their disease 3 to 6 months after completing irradiation therapy should receive antiplasma cell systemic therapy, the most effective being high dose chemotherapy with autologous stem cell transplantation. Lenalidomide seems to have a high efficacy with manageable toxicity. Thalidomide and proteasome inhibitors like bortezomib are also effective, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy.

Cutaneous presentation of adult T-cell leukemia/lymphoma (ATLL). Single-center study on 37 patients in metropolitan France between 1996 and 2016.

INTRODUCTION: Adult T-cell leukemia/lymphoma (ATLL) is a hematological malignancy associated with chronic HTLV-1 infection. AIM: To describe skin lesions in ATLL. METHODS: A descriptive, retrospective study between 1996 and 2016, including all patients diagnosed with ATLL at Saint-Louis Hospital (Paris, France). RESULTS: Thirty-seven ATLL patients were included. Fifteen patients (41%) had a cutaneous localization of the disease, which was present from the beginning of the disease for two thirds of them. ATLL types in patients with cutaneous localization of the disease were as follows: lymphoma, n=5, chronic, n=4, smoldering, n=4, acute, n=2. Half the patients had 2 or more cutaneous manifestations. The cutaneous localizations observed were as follows: nodulotumoral (n=8), plaques (n=7), multipapular (n=6), macular (n=4), purpuric (n=2). Among the 15 patients with cutaneous localization, median overall survival was significantly shorter in the acute and lymphoma types compared to the smoldering and chronic types (8.7 months vs. 79 months, P=0.003). DISCUSSION: ATLL is a hematologic malignancy with variable expression that is diagnosed only very rarely in metropolitan France, but that should be sought in patients from countries with high HTLV-1 prevalence in the event of a chronic eruption with patches, papules, plaques and/or tumors. The chronic and smoldering types are relatively indolent, whereas the acute and lymphoma forms have a poor prognosis.

Nucleotide excision repair is a potential therapeutic target in multiple myeloma.

Despite the development of novel drugs, alkylating agents remain an important component of therapy in multiple myeloma (MM). DNA repair processes contribute towards sensitivity to alkylating agents and therefore we here evaluate the role of nucleotide excision repair (NER), which is involved in the removal of bulky adducts and DNA crosslinks in MM. We first evaluated NER activity using a novel functional assay and observed a heterogeneous NER efficiency in MM cell lines and patient samples. Using next-generation sequencing data, we identified that expression of the canonical NER gene, excision repair cross-complementation group 3 (ERCC3), significantly impacted the outcome in newly diagnosed MM patients treated with alkylating agents. Next, using small RNA interference, stable knockdown and overexpression, and small-molecule inhibitors targeting xeroderma pigmentosum complementation group B (XPB), the DNA helicase encoded by ERCC3, we demonstrate that NER inhibition significantly increases sensitivity and overcomes resistance to alkylating agents in MM. Moreover, inhibiting XPB leads to the dual inhibition of NER and transcription and is particularly efficient in myeloma cells. Altogether, we show that NER impacts alkylating agents sensitivity in myeloma cells and identify ERCC3 as a potential therapeutic target in MM.

Current anti-myeloma therapies in renal manifestations of monoclonal light chain-associated Fanconi syndrome: a retrospective series of 49 patients.

We retrospectively reviewed 49 patients with light chain (LC) Fanconi syndrome (FS). Patients presented with chronic kidney disease (median estimated glomerular filtration rate (eGFR) of 33 ml/min/1.73 m2) and tubular proteinuria. All patients tested had elevated fractional excretion of phosphate, uric acid, generalized aminoaciduria and/or normoglycemic glycosuria. Thirty-eight patients had monoclonal gammopathy of renal significance and eleven patients had an overt hematological malignancy. The monoclonal LC isotype was kappa in 46/49 cases. Kidney biopsy in 39 patients showed various proximal tubular lesions and characteristic LC intracytoplasmic crystalline inclusions in 24 patients. Forty-two patients received chemotherapy. Patients with plasma cell proliferation (n=38) received bortezomib-based regimens (n=11), immunomodulatory agents (n=7) or alkylating agents (n=6). High-dose melphalan (HDM) followed by autologous stem cell transplantation was performed in 14 patients. Hematological response was obtained in 90% of evaluable patients, assessed on serum free light chains (FLC). GFR remained stable as long as hematological response was maintained and declined when serum FLC level rebounded. Improvement in proximal tubule function occurred in 13 patients. In patients with LC-associated FS, chemotherapy using HDM and/or new generation anti-myeloma agents can stabilize renal function and improve proximal tubule function. Serum FLC should be used to assess the hematological response, related to renal outcome.

Safe and prolonged survival with long-term exposure to pomalidomide in relapsed/refractory myeloma.

BACKGROUND: The IFM2009-02 trial studied pomalidomide (4 mg daily, 21/28 versus 28/28) and dexamethasone in very advanced relapsed or refractory multiple myeloma (RRMM). We observed that 40% of patients had a prolonged progression-free survival (PFS) and subsequently overall survival (OS). We sought to analyze the characteristics of these patients and study the effect of long exposure to pomalidomide. DESIGN: We separated the studied population into two groups: 3 months to 1 year (<1 year) and more than 1 year (≥1 year) of treatment with pomalidomide and dexamethasone based on clinical judgment and historical control studies. We then analyzed the characteristics of patients according to duration of treatment. RESULTS: The overall response rate (ORR) for the <1-year group was 43%, the median PFS 4.6 months [95% confidence interval (95% CI) 3.8-6.4] with only 6% at 12 months, and the median OS was 15 months (11.7-20.3) and 40% at 18 months. For the ≥1-year group, the response rate and survival were strikingly different, ORR at 83%, median PFS 20.7 months (14.7-35.4), median OS not reached, and 91% at 18 months. CONCLUSION: Pomalidomide and dexamethasone favored prolonged and safe exposure to treatment in 40% of heavily treated and end-stage RRMM, a paradigm shift in the natural history of RRMM characterized with a succession of shorter disease-free intervals and ultimately shorter survival. Although an optimization of pomalidomide-dexamethasone regimen is warranted in advanced RRMM, we claim that pomalidomide has proven once more to change the natural history of myeloma in this series, which should be confirmed in a larger study.

[Pomalidomide for multiple myeloma]. / Le pomalidomide dans le myélome multiple.

Once characterized by a very poor outcome, multiple myeloma (MM) now has a significantly prolonged survival, with major improvements allowed by the use of "novel agents": proteasome inhibitors (first-in-class bortezomib) and immunomodulatory compounds (IMiDs; first-in-class thalidomide and lenalidomide). However, the vast majority - if not all - of patients with MM ultimately end up being refractory to all existing drugs, including these efficient novel agents. There is a clear unmet medical need in this situation, which warrants the development of the next generation of proteasome inhibitors and IMiDs, as well as new drug classes. This review focuses on pomalidomide, the next generation IMiD, recently approved by the US FDA and the EMA for patients with relapsed or refractory MM who have received at least two prior therapies, including lenalidomide and bortezomib, and have demonstrated disease progression on their last therapy.

Predicting oculomotor behaviour from correlated populations of posterior parietal neurons.

Oculomotor function critically depends on how signals representing saccade direction and eye position are combined across neurons in the lateral intraparietal (LIP) area of the posterior parietal cortex. Here we show that populations of parietal neurons exhibit correlated variability, and that using these interneuronal correlations yields oculomotor predictions that are more accurate and also less uncertain. The structure of LIP population responses is therefore essential for reliable read-out of oculomotor behaviour.

Brain-machine interface for eye movements.

A number of studies in tetraplegic humans and healthy nonhuman primates (NHPs) have shown that neuronal activity from reach-related cortical areas can be used to predict reach intentions using brain-machine interfaces (BMIs) and therefore assist tetraplegic patients by controlling external devices (e.g., robotic limbs and computer cursors). However, to our knowledge, there have been no studies that have applied BMIs to eye movement areas to decode intended eye movements. In this study, we recorded the activity from populations of neurons from the lateral intraparietal area (LIP), a cortical node in the NHP saccade system. Eye movement plans were predicted in real time using Bayesian inference from small ensembles of LIP neurons without the animal making an eye movement. Learning, defined as an increase in the prediction accuracy, occurred at the level of neuronal ensembles, particularly for difficult predictions. Population learning had two components: an update of the parameters of the BMI based on its history and a change in the responses of individual neurons. These results provide strong evidence that the responses of neuronal ensembles can be shaped with respect to a cost function, here the prediction accuracy of the BMI. Furthermore, eye movement plans could be decoded without the animals emitting any actual eye movements and could be used to control the position of a cursor on a computer screen. These findings show that BMIs for eye movements are promising aids for assisting paralyzed patients.

Decoding the activity of neuronal populations in macaque primary visual cortex.

Visual function depends on the accuracy of signals carried by visual cortical neurons. Combining information across neurons should improve this accuracy because single neuron activity is variable. We examined the reliability of information inferred from populations of simultaneously recorded neurons in macaque primary visual cortex. We considered a decoding framework that computes the likelihood of visual stimuli from a pattern of population activity by linearly combining neuronal responses and tested this framework for orientation estimation and discrimination. We derived a simple parametric decoder assuming neuronal independence and a more sophisticated empirical decoder that learned the structure of the measured neuronal response distributions, including their correlated variability. The empirical decoder used the structure of these response distributions to perform better than its parametric variant, indicating that their structure contains critical information for sensory decoding. These results show how neuronal responses can best be used to inform perceptual decision-making.