CLL-461 Humoral Response to COVID-19 Vaccine: A Challenge in CLL

Chronic lymphocytic leukaemia (CLL) is associated with some degree of immune dysfunction as a result of the disease itself and/or treatment. COVID-19 has a major impact on patients with CLL who are at increased risk for severe disease and death. In this study, we aimed to understand the efficacy of anti-SARS-CoV-2 vaccines in patients with CLL. From January 2021, we collected data on 166 vaccinated patients with CLL followed at our site. Median age was 68 years (range 41-92); 43 (26%) were treatment-naïve (TN), 25 (15%) were previously treated, 95 (57%) were on active therapy, and 3 (2%) were experiencing relapse. Most patients received BNT162b2 (87%), followed by mRNA-1273 (4%) and ChAdOx1-S (3%); data is missing in 6%. Serology testing was performed with the SARS-CoV-2 S1/S2 IgG assay (Elecsys® Anti-SARS-CoV-2) 2 to 3 weeks after second and third vaccine doses and considered negative for antibody titers below 0.4 U/ml. Vaccine response was evaluated post-dose 2 in 119 patients and post-dose 3 in 74 patients. Post second dose, a higher seroconversion rate was observed in TN patients and those with sustained clinical response after therapy discontinuation (42% and 46% respectively) compared with actively treated patients (20.5%; [p=0.024; p=0.048]). Antibody response rate in patients receiving BTKi was considerably lower 19.7% (12/61). Three (42.9%) out of 7 patients who received venetoclax monotherapy seroconverted. None of the patients exposed to anti-CD20 antibodies (3/8 with targeted therapy, 2/8 with chemotherapy, 3/8 as single agent) <12 months before vaccination responded. Among patients actively treated who failed to achieve a humoral response after two-dose, 25.6% responded to the third dose of vaccine, although with a weak antibody level (median 8.64 U/ml, range 0.55-175). Overall, post third dose a higher median (IQR) antibody titer (127.9 U/mL; 0.55-2500) was observed compared to one post second dose (19.2 U/ml; 0.86-2500) in patients on therapy. Notably, all patients in clinical remission after treatment present titers above the upper limit of quantification (>2500 U/mL) post third dose. Conclusions: Humoral immune response to the COVID-19 vaccine is impaired in most patients with CLL and correlates with treatment status.

Prognostic impact of tumor-associated macrophages, lymphocyte-to-monocyte and neutrophil-to-lymphocyte ratio in diffuse large B-cell lymphoma

INTRODUCTION

Microenvironment has a prognostic influence in diffuse large B-cell lymphoma (DLBCL); among its components, tumor-associated macrophages (TAM) play a leading role. TAM can be classified into M1 (anti-tumor) and M2 (pro-tumor). Another prognostic factor could be represented by lymphocyte-to-monocyte and neutrophil-to-lymphocyte ratio (LMR and NLR).

OBJECTIVE

The aim of the study is to evaluate the prognostic impact of M1 and M2 TAM subtypes, LMR and NLR in DLBCL.

METHODS

We analyzed 37 consecutive patients between 2009 and 2013. Out of 37 patients, 28/37 (75.6%) received R-CHOP/CHOP-like regimens, 9/37 (24.4%) less intensive therapies. Immunohistochemistry was performed with antibodies against CD68 and CD163. We divided our cohort into 2 categories according to the Steidl score. TAM who coexpressed CD68 and CD163 were considered as M2. For LMR and NLR we used previously published cut-offs of 2.71 and 2.81.

RESULTS

CR rate was 70.3%; we did not record a significant correlation between CD68+ TAM, CD163+ TAM, CD68+/CD163+ TAM, LMR, NLR and CR. We observed a reduced PFS in patients with IPI ≥ 2 and high M2 TAM expression and a trend between higher expression of CD68+ TAM and improved PFS.

CONCLUSION

M2 TAM could have a prognostic role for IPI ≥ 2 DLBCL patients receiving R-CHOP, which thus warrants further investigation.

Durable response after VNCOP-B and rituximab in an elderly patient with high-grade B-cell lymphoma

OBJECTIVES AND METHODS

 High-grade B-cell lymphoma, NOS (HGBL) have an aggressive clinical behavior and poor outcome using regimens currently employed for diffuse large B-cell lymphoma (DLBCL) such as rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Promising results have been reported with more intensive regimens but this strategy is not suitable for elderly or unfit patients. Rituximab in association with cyclophosphamide, mitoxantrone, vincristine, etoposide, bleomycin, and prednisone (R-VNCOP-B) demonstrated high efficacy and manageable toxicity as first-line treatment for elderly aggressive non-Hodgkin lymphoma patients.

RESULTS AND CONCLUSION

In this case study, we report the rapid improvement, long-lasting complete remission, and mild toxicity of R-VNCOP-B regimen in an elderly, triple-expressor HGBL patient, with aggressive disease and poor-risk profile.

Therapeutic Use of Brentuximab Vedotin in CD30+ Hematologic Malignancies

The CD30 antigen is strongly expressed on neoplastic cells in classical Hodgkin lymphoma (HL), anaplastic large cell lymphoma (ALCL) and other hematologic malignancies (such as DLBCL and cutaneous TCL), while is almost undetectable on healthy tissues, representing an ideal immunotherapeutic target. Since unconjugated anti-CD30 antibody (SGN-30) demonstrated limited clinical activity, researchers' effort aimed to create an antibody-drug conjugate (ADC), leading to discovery of SGN-35 (brentuximab vedotin), in which an anti-CD30 antibody is linked to the antimitotic agent monomethyl auristatin E (MMAE). In the first phase I study in CD30+ hematologic malignancies (the majority of patients with HL), the maximum tolerated dose was fixed respectively at 1.8mg/Kg every 3 weeks, overall response rate (ORR) and complete response (CR) rate were 38% and 24%. In 2 subsequent phase II studies, amazing results were reported, that permitted accelerated FDA approval for relapsed/refractory patients and led to the development of many clinical trials including BV as first-line HL and ALCL treatment. Moreover, as CD30 antigen may be expressed by other malignancies, the potential therapeutic application is increasing, including at least diffuse large B-cell lymphoma, T-cell lymphomas other than ALCL and cutaneous lymphoproliferative disorders. BV is administrated as outpatient regimen and is usually well tolerated; sensorial peripheral neuropathy represents the most common toxic effect, although it is dose-dependent and at least partially reversible in most cases, after dose reduction and/or treatment ending.

Chemoimmunotherapy with oral low-dose fludarabine, cyclophosphamide and rituximab (old-FCR) as treatment for elderly patients with chronic lymphocytic leukaemia

Median age at diagnosis for chronic lymphocytic leukaemia (CLL) patients is now 72 years, thus a consistent number of patients may not tolerate standard doses i.v. of fludarabine, cyclophosphamide and rituximab (FCR), the best available therapy, due to unacceptable myelotoxicity and risk of severe infections. We studied safety and efficacy of the addition of rituximab to the oral low-dose FC regimen (old-FCR) in a selected population of 30 elderly (median age 75, 15 untreated, 15 treated with 1 prior therapy) CLL patients. Complete remission (CR) rate was 80% in the untreated patients (overall response rate, ORR 93%), and 30% in pretreated patients (ORR 74%). Progression free survivals (PFS) were 45 months and 30 months in the untreated and treated patients, respectively. In patients achieving CR, old-FCR led to PFS of 67 months. Moreover, haematological toxicity was mild (grade 3-4: 15%) and patients were treated mostly in outpatient clinic. Old-FCR could be a good therapy option for elderly CLL patients outside clinical trials, larger studies are needed to confirm our findings.