Addition of Niraparib to Best Supportive Care as Maintenance Treatment in Patients with Advanced Urothelial Carcinoma Whose Disease Did Not Progress After First-line Platinum-based Chemotherapy: The Meet-URO12 Randomized Phase 2 Trial.

BACKGROUND: Platinum-based chemotherapy (PBCT) is the standard first-line treatment for advanced urothelial carcinoma (UC). Potential cross-sensitivity can be hypothesized between platinum drugs and poly-ADP ribose-polymerase (PARP) inhibitors. OBJECTIVE: To compare maintenance treatment with the PARP inhibitor niraparib plus best supportive care (BSC) versus BSC alone in patients with advanced UC without disease progression after first-line PBCT. DESIGN, SETTING, AND PARTICIPANTS: Meet-URO12 is a randomized, multicenter, open-label phase 2 trial. Patients with advanced UC, without disease progression after four to six cycles of PBCT, with Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, were enrolled between August 2019 and March 2021. Randomization was stratified by ECOG performance status (0/1) and response to PBCT (objective response/stable disease). INTERVENTION: Patients were randomized (2:1) to experimental arm A (niraparib 300 or 200 mg daily according to body weight and baseline platelets, plus BSC) or control arm B (BSC alone). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was progression-free survival (PFS). The analysis was performed on an intention-to-treat basis. The secondary endpoints reported in this primary analysis are progression-free rate at 6 mo and safety (adverse event rate). RESULTS AND LIMITATIONS: Fifty-eight patients were randomized (39 in arm A and 19 in arm B). The median age was 69 yr, ECOG performance status was 0 in 66% and 1 in 34%; and the best response with chemotherapy was objective response in 55% and stable disease in 45%. The median PFS was 2.1 mo in arm A and 2.4 mo in arm B (hazard ratio 0.92; 95% confidence interval 0.49-1.75, p = 0.81). The 6-mo progression-free rates were 28.2% and 26.3%, respectively. The most common adverse events with niraparib were anemia (50%, grade [G]3 11%), thrombocytopenia (37%, G3-4 16%), neutropenia (21%, G3 5%), fatigue (32%, G3 16%), constipation (32%, G3 3%), mucositis (13%, G3 3%), and nausea (13%, G3 3%). The main limitation of the study is the small sample size: in March 2021, approval of maintenance avelumab for the same setting rendered randomization of patients in the control arm to BSC alone unethical, and accrual was stopped prematurely. CONCLUSIONS: Addition of maintenance niraparib to BSC after first-line PBCT did not demonstrate a significant improvement in PFS in patients with UC. These results do not support the conduction of a phase 3 trial with single agent niraparib in this population. PATIENT SUMMARY: In this trial, we tested the efficacy of niraparib as maintenance treatment in patients affected by advanced urothelial cancer after the completion of first-line chemotherapy. We could not demonstrate a significant improvement in progression-free survival with maintenance niraparib.

KRAS-Driven Lung Adenocarcinoma and B Cell Infiltration: Novel Insights for Immunotherapy.

Non-small-cell lung cancer, histologically classified into adenocarcinoma (AD) and squamous cell carcinoma, is one of the most deadly malignancies worldwide. Lung AD (LUAD) could benefit of a plethora of target therapies and, in the last few years, also of immunotherapies. Here we focused on a real-life cohort of LUAD and The Cancer Genome Atlas (TCGA)-LUAD dataset aiming to gain insights into the immune contexture of such a malignancy. We explored the mutational status of 41 genes and the expression of 94 genes, related to immune-checkpoint, inflammation, and stromal microenvironment. Surprisingly, we found that our cohort has a very low mutational burden if we consider our panel as its surrogate. Regarding gene expression data, we identified 31 genes significantly deregulated in tumor tissues compared with a pool of normal samples. Unsupervised hierarchical clustering of the deregulated genes is able to identify two clusters of tumor samples, differently enriched in alterations in actionable genes. In particular, we identified a cluster enriched in patients carrying KRAS alterations. In silico deconvolution, that is the inferring of tumor microenvironment composition by gene expression data, through TIMER algorithm has been performed to explore immune microenvironment. Estimation performed on our gene expression matrix showed that B cell infiltration is lower in the KRAS-mutated enriched cluster, as in the TCGA-LUAD dataset. Such a finding has been validated in situ through immunohistochemistry in an independent cohort. Moreover, cases in LUAD-TCGA with low B cell infiltration have a significantly worse overall survival than those with higher levels. In the real-life cohort we observed that cases belonging to cluster enriched in KRAS-mutated patients have a poor outcome. LUAD driven by KRAS mutation represents an unmet clinical need, being refractory to pharmacological inhibition. Our results link KRAS mutations to B cell infiltration. Thus, the present findings could be helpful in a better definition of immunotherapeutic approaches for KRAS mutated patients.

Modulation of CD20 antigen expression after rituximab treatment: a retrospective study in patients with chronic lymphocytic leukemia.

BACKGROUND: CD20 antigen down-modulation by anti-CD20 rituximab treatment is a well-recognized phenomenon in patients with non-Hodgkin's lymphoma. However, few data are currently available on this topic in other lymphoproliferative disorders, in particular in chronic lymphocytic leukemia (CLL). OBJECTIVE: The aim of this study was to establish how many patients with CLL show a disappearance of CD20 antigen after salvage treatment with rituximab and its possible clinical significance. METHODS: We sequentially analyzed CD20 expression by flow cytometry in patients treated with rituximab in combination with other agents for relapsed/resistant disease. RESULTS: Eleven white patients with CLL (6 females, 5 males; median age, 71.6 years [range, 60-84 years]) were included in the study. Three of the 11 patients were not positive for CD20 due to complete response at baseline. Four of the remaining 8 patients (50%) lacked CD20 antigen on neoplastic cells after monoclonal antibody treatment. Two of them developed Richter's syndrome and died within 4 months. The phenomenon was transient in the other 2 patients, who were alive after a follow-up of 25 and 26 months, respectively, with CD20-positive recurrent disease. CONCLUSIONS: In this study, CD20 antigen disappearance in patients with CLL treated with rituximab-containing salvage regimens occurred in 4 of 8 (50%) tested patients, half of whom developed Richter's syndrome. [Note: Since the initial writing and submission, a third patient developed Richter's syndrome.] In 2 patients (50%), CD20 returned at progression.

Response to recombinant erythropoietin alpha, without the adjunct of granulocyte-colony stimulating factor, is associated with a longer survival in patients with transfusion-dependent myelodysplastic syndromes.

This was a retrospective, comparative study focused on the extended follow-up of 192 transfusion-dependent patients with myelodysplastic syndromes treated (n. 83) or not treated (n. 109) with recombinant erythropoietin alpha (r-EPO) as single agent during the course of their disease. The results supported the safety of this treatment in the long term and also showed a significant survival advantage (median 52 months vs. 31 months, p<0.0095) in responding patients as compared to non-responding ones or to subjects never treated with r-EPO. At multivariate analysis, response to r-EPO maintained an independent prognostic value on OS.

T cells support osteoclastogenesis in an in vitro model derived from human multiple myeloma bone disease: the role of the OPG/TRAIL interaction.

The development of multiple myeloma (MM) bone disease is mediated by increased number and activity of osteoclasts (OCs). Using an in vitro osteoclastogenesis model consisting of unstimulated and unfractionated peripheral blood mononuclear cells (PBMCs) from patients with MM, we showed that T cells support the formation of OCs with longer survival. Different from T-cell-depleted MM PBMC cultures, exogenous macrophage-colony stimulating factor (M-CSF) and receptor activator of nuclear factor-kappaB ligand (RANKL) were necessary for the formation of OCs; however, they did not exhibit longer survival. We found up-regulated production of RANKL, osteoprotegerin (OPG), and TNF-related apoptosis-inducing ligand (TRAIL) by fresh MM T cells. Despite high OPG levels, the persistence of osteoclastogenesis can be related to the formation of the OPG/TRAIL complex demonstrated by immunoprecipitation experiments and the addition of anti-TRAIL antibody which decreases OC formation. OCs overexpressed TRAIL decoy receptor DcR2 in the presence of MM T cells and death receptor DR4 in T-cell-depleted cultures. In addition, increased Bcl-2/Bax (B-cell lymphoma-2/Bcl2-associated protein X) ratio, following Bcl-2 up-regulation, was detected in OCs generated in the presence of T cells. Our results highlight that MM T cells support OC formation and survival, possibly involving OPG/TRAIL interaction and unbalanced OC expression of TRAIL death and decoy receptors.