Persistent SARS-CoV-2 infection with multiple clinical relapses in two patients with follicular lymphoma treated with bendamustine and obinutuzumab or rituximab.

PURPOSE: People with hematologic malignancies have a significantly higher risk of developing severe and protracted forms of SARS-CoV-2 infection compared to immunocompetent patients, regardless of vaccination status. RESULTS: We describe two cases of prolonged SARS-CoV-2 infection with multiple relapses of COVID-19 pneumonia in patients with follicular lymphoma treated with bendamustine and obinutuzumab or rituximab. The aim is to highlight the complexity of SARS-CoV-2 infection in this fragile group of patients and the necessity of evidence-based strategies to treat them properly. CONCLUSIONS: Patients with hematological malignancies treated with bendamustine and anti-CD20 antibodies had a significant risk of prolonged and relapsing course of COVID-19. Specific preventive and therapeutic strategies should be developed for this group of patients.

Treatment of COVID-19 with convalescent plasma in patients with humoral immunodeficiency - Three consecutive cases and review of the literature.

Patients lacking humoral response have been suggested to develop a less severe COVID-19, but there are some reports with a prolonged, relapsing or deadly course. From April 2020, there is growing evidence on the benefits of COVID-19 convalescent plasma (CCP) for patients with humoral immunodeficiency. Most of them had a congenital primary immunodeficiency or were on treatment with anti CD20 antibodies. We report on three patients treated in our hospital and review thirty-one more cases described in the literature. All patients but three resolved clinical picture with CCP. A dose from 200 to 800ml was enough in most cases. Antibody levels after transfusion were negative or low, suggesting consumption of them in SARS-CoV-2 neutralization. These patients have a protracted clinical course shortened after CCP. CCP could be helpful for patients with humoral immunodeficiency. It avoid relapses and chronification. CCP should be transfused as early as possible in patients with COVID-19 and humoral immunodeficiency.

Convalescent Plasma Treatment of Patients Previously Treated with B-Cell-Depleting Monoclonal Antibodies Suffering COVID-19 Is Associated with Reduced Re-Admission Rates.

Patients receiving treatment with B-cell-depleting monoclonal antibodies, such as anti-CD20 monoclonal antibodies, such as rituximab and obinutuzumab, either for hematological disease or another diagnosis, such as a rheumatological disease, are at an increased risk for medical complications and mortality from COVID-19. Since inconsistencies persist regarding the use of convalescent plasma (CP), especially in the vulnerable patient population that has received previous treatment with B-cell-depleting monoclonal antibodies, further studies should be performed in thisdirection. The aim of the present study was to describe the characteristics of patients with previous use of B-cell-depleting monoclonal antibodies and describe the potential beneficial effects of CP use in terms of mortality, ICU admission and disease relapse. In this retrospective cohort study, 39 patients with previous use of B-cell-depleting monoclonal antibodies hospitalized in the COVID-19 department of a tertiary hospital in Greece were recorded and evaluated. The mean age was 66.3 years and 51.3% were male. Regarding treatment for COVID-19, remdesivir was used in 89.7%, corticosteroids in 94.9% and CP in 53.8%. In-hospital mortality was 15.4%. Patients who died were more likely to need ICU admission and also had a trend towards a longer hospital stay, even though the last did not reach statistical significance. Patients treated with CP had a lower re-admission rate for COVID-19 after discharge. Further studies should be performed to identify the role of CP in patients with treatment with B-cell-depleting monoclonal antibodies suffering from COVID-19.

Prolonged SARS-CoV-2 Infection and Organizing Pneumonia in a Patient with Follicular Lymphoma, Treated with Obinutuzumab-Challenging Recognition and Treatment.

A Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causing coronavirus disease 2019 (COVID-19) led to a pandemic outbreak in 2019. COVID-19's course and its treatment in immunocompromised patients are uncertain. Furthermore, there is a possibility of protracted SARS-CoV-2 infection and the need for repeated antiviral treatment. Monoclonal antibodies against CD20, which are used, among other things, in the therapy of chronic lymphocytic leukaemia and follicular lymphoma, can induct immunosuppression. We present a case report of a patient with follicular lymphoma, treated with obinutuzumab, who was diagnosed with prolonged, ongoing SARS-CoV-2 infection and related organizing pneumonia. The recognition and the treatment were challenging which makes this case noteworthy. Antiviral therapy with several medications was administrated to our patient and their temporary, positive effect was observed. Moreover, high-dose intravenous immunoglobulin was applied, because slowly decreasing IgM and IgG levels were observed. The patient also received standard treatment of organizing pneumonia. We believe that such a complex approach can create an opportunity for recovery. Physicians should be conscious of the course and treatment possibilities facing similar cases.

A case of prolonged COVID-19 treated with tixagevimab/cilgavimab.

A 54-year-old woman presented to our hospital with a fever and cough. The patient had a medical history of follicular lymphoma treated with obinutuzumab. She was infected with an omicron variant of coronavirus disease 2019 and developed viral pneumonia. Antibiotics, molnupiravir, sotrovimab, and prednisolone were administered but were ineffective. The patient's symptoms and pneumonia persisted. She could not produce antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) because she was administered obinutuzumab. Finally, when we administered 300 mg of tixagevimab and cilgavimab, pneumonia immediately improved. However, the infection was prolonged for more than 4 months. Patients treated with anti-CD20 monoclonal antibodies may have a prolonged SARS-CoV-2 infection. In such cases, tixagevimab/cilgavimab may be effective.

Early efficacy and safety of obinutuzumab with chemotherapy in previously untreated patients with follicular lymphoma: A real-world retrospective report of the Polish Lymphoma Research Group.

BACKGROUND: The first-line obinutuzumab-based immunochemotherapy improves the outcome of patients with follicular lymphoma (FL) compared with rituximab-based regimens. However, infusion-related reactions occur in almost half of patients during the 1st obinutuzumab administration. OBJECTIVES: The study aimed to evaluate the early effectiveness and safety of obinutuzumab-based induction regimens in a real-world setting. MATERIAL AND METHODS: Outcomes of patients diagnosed with FL and treated with obinutuzumab between January 2020 and September 2021 were analyzed. RESULTS: The study group included 143 treatment-naïve patients with FL. The median age was 52 years (range: 28-89 years); 45.1% of patients had a high-risk disease as assessed using the Follicular Lymphoma International Prognostic Index (FLIPI). Induction chemotherapy included: O-CVP (obinutuzumab, cyclophosphamide, vincristine, prednisolone) in 49.0% of patients, O-CHOP (O-CVP plus doxorubicin) in 28.7% and O-BENDA (obinutuzumab, bendamustine) in 22.4%. Complete response (CR) and partial response (PR) rates were 69.9% and 26.5%, respectively. There was no difference in response rates between different regimens (p = 0.309). Maintenance was started in 115 patients (85.2%). In the 1st cycle, obinutuzumab was administered as a single 1000-milligram infusion in 47.9% of patients, whereas in 52.1%, initial infusions were split over 2 days (100 mg/900 mg). Infusion-related reactions were reported only during the 1st administration of obinutuzumab in 9.1% of patients, with a similar incidence in those receiving the total dose on a single day or split over 2 days (p = 0.458). The most common adverse events were hematological. Five patients died from coronavirus disease 2019 (COVID-19). CONCLUSION: The early responses to induction regimens and adverse events profile were similar for every type of induction treatment. The infusion-related reactions were rare and limited to the 1st dose of obinutuzumab.

Prolonged SARS-CoV-2 Infection With Common Features in Two Patients Receiving Anti-CD20 Therapy.

BACKGROUND/AIM: Anti-CD20-depleting monoclonal antibodies predispose patients to the development of severe disease of SARS-CoV-2 infection. These antibodies are given as backbone or maintenance therapy in patients with hematological malignancies and rheumatology diseases, inducing effective B-cell depletion along with antibody-dependent cell-mediated cytotoxicity (ADCC) and disrupting infection-protective antibody responses. CASE REPORT: We describe two cases of prolonged SARS-CoV-2 infection with common features, in two patients receiving anti-CD20 therapies, the first for chronic lymphocytic leukemia (CLL) and the second for rheumatoid arthritis (RA). For CLL patient, despite administration of antiviral therapy, signs and symptoms of SARS-CoV-2 infection persisted for 43 days, with resolution and lymphocyte recovery from day 33. For RA patient, despite administration of two courses of antiviral therapy, signs and symptoms of SARS-CoV-2 infection persisted for 47 days, without resolution and lymphocyte recovery, leading to a fatal outcome due to acute respiratory distress syndrome (ARDS) and unspecified sepsis. CONCLUSION: These two cases highlight the risk for persistent SARS-CoV-2 infection in patients treated with anti-CD20 monoclonal antibodies and support a role for cellular immunity recovery for disease control.

Sequential Treatment by Antiviral Drugs Followed by Immunosuppressive Agents for COVID-19 Patients with Hematological Malignancy.

Background: The detailed treatment regimen of COVID-19 patients with hematological malignancies has been unclear, and some fatalities have occurred, although combination therapy with antiviral agents and corticosteroids has been established for moderate to severe COVID-19 patients. Case Series: Case 1 was a 57-year-old woman who had malignant lymphoma and received CHOP therapy with obinutuzumab, and case 2 was a 70-year-old-man who had myeloma and received molecular targeted therapy with weekly corticosteroid. In both cases, SARS-CoV-2 genes and antigens were detected from their nasal swabs, and treatment was started for moderate to severe COVID-19. Case 1 received antiviral agents with high doses of corticosteroids for a long term simultaneously, but the high titer of viral antigens in her nasal swabs persisted. Ground-glass opacities and interstitial shadows also worsened in both lungs, and she finally died on day 60. In contrast, in case 2, antiviral agents were started first, and restarted the immunosuppressive agents, such as gamma globulin and corticosteroids after no titer of SARS-CoV-2 antigens was confirmed. The patient survived, and his abnormal chest shadows showed gradual improvement. Both of the patients received two vaccinations, but showed the low antibody titers for SARS-CoV-2. Conclusion: Administration of both antiviral agents and corticosteroids has been recommended for moderate to severe COVID-19 patients, but in patients with hematological malignancies, it might be better to use antiviral agents first to reduce the viral titers, and then add steroid and related immunosuppressive agents later appropriately to inhibit the excessive inflammatory state. The dose, timing, and order of the antivirals and immunosuppressive agents for COVID-19 should be considered carefully in the patients with hematological malignancies who showed low vaccine effectiveness.

Monoclonal anti-CD20 antibodies in lymphomas therapy during the COVID-19 pandemic: pro and contra

The review presents the results of a combined analysis of literature data and own clinical observations regarding the safety and feasibility of using monoclonal anti-CD20 antibodies in the treatment of B-cell lymphoproliferative diseases during the COVID-19 pandemic. The main points of the pathogenesis of the influence of monoclonal anti-CD20 antibodies on the course of COVID-19 are described. The current trends in the modification of the accepted algorithms of lymphoproliferative diseases therapy with the inclusion of monoclonal anti-CD20 antibodies are summarized, and the possibilities of specific prevention by vaccination against COVID-19 are also considered. Copyright © 2022 ABV-Press Publishing House. All rights reserved.

Treatment of COVID-19 with convalescent plasma in patients with humoral immunodeficiency - Three consecutive cases and review of the literature.

Patients lacking humoral response have been suggested to develop a less severe COVID-19, but there are some reports with a prolonged, relapsing or deadly course. From April 2020, there is growing evidence on the benefits of COVID-19 convalescent plasma (CCP) for patients with humoral immunodeficiency. Most of them had a congenital primary immunodeficiency or were on treatment with anti CD20 antibodies. We report on three patients treated in our hospital and review thirty-one more cases described in the literature. All patients but three resolved clinical picture with CCP. A dose from 200 to 800ml was enough in most cases. Antibody levels after transfusion were negative or low, suggesting consumption of them in SARS-CoV-2 neutralization. These patients have a protracted clinical course shortened after CCP. CCP could be helpful for patients with humoral immunodeficiency. It avoid relapses and chronification. CCP should be transfused as early as possible in patients with COVID-19 and humoral immunodeficiency.

Treatment with obinutuzumab leads to worse outcomes in hematological patients diagnosed with Omicron variant COVID-19

Background: Hematological malignancies (HM) patients treated with anti-CD20s are at a higher risk for COVID-19 complications, however, little is known about the difference between these agents. Aim: To investigate the prognosis of HM COVID-19 pateints treated with obinutuzumab in comparison to rituximab. Methods: Single-center population-based cohort study including all HM patients treated with anti-CD20s from June 2021 to April 2022. Diagnosis of COVID-19 was based on positive SARS-CoV-2 PCR omicron variant. The Median follow-up was four months. Results: Among 143 HM patients, 47 were diagnosed with COVID- 19, 27 in the rituximab group and 20 in the obinutuzumab group. All obinutuzumab-treated patients had indolent HM, versus only 40.7% among the rituximab group (p <0.001). 13/20 of the obinutuzumab group (65.0%) received anti-CD20s as maintenance therapy, while most of the rituximab patients, 21/27 (77.8%) were on induction phase therapy (p = 0.003). COVID-19 prognosis was worse among obinutuzumab patients with higher admission rates (60.0% vs. 25.9%, p = 0.019), more patients with severe-critical disease (35.0% vs.7.4%, p = 0.017), and accounts for all mortality cases (3/20 vs. 0/27, p = 0.038). Conclusions: Omicron-variant COVID-19 disease outcome was worse among HM patients treated with obinutuzumab comparing to rituximab. As this treatment has not been shown to increase overall survival when given as maintenance, In our opinion, it may be prudent to delay treatment with obinutuzumab or replace it with a less potent anti-CD20 as long as the COVID-19 epidemic continues.

IBRUTINIB PLUS VENETOCLAX IN PATIENTS WITH COMPLEX KARYOTYPE AND CHRONIC LYMPHOCYTIC LEUKEMIA

Background: In the largest study of Baliakas et al. (2019) the presence of at least 5 abnormalities, was associated with dismal clinical outcome, independently of the somatic hypermutation status and TP53 status. The presence of 3 or 4 aberrations is defined as clinically relevant in the absence of TP53. Studies by Kittai (2021) and Al-Sawaf (2020) showed the impact of karyotypic complexity on survival in patients with chronic lymphocytic leukemia (CLL) treated with ibrutinib or venetoclax. The complex karyotype (CK) is a topic that is being intensively researched, both in the aspect of increasing karyotypic complexity stratification and clonal evolution. Optimal therapy for patients with CLL has not yet been developed. The combination therapy of ibrutinib and venetoclax was superior to chlorambucil and obinutuzumab in terms of undetectable minimal residual disease (MRD) responses according to data from the GLOW trial (Tunir, 2021). The importance of achieving a complete response with undetectable MRD as the goal of therapy in CLL was proposed (Montserrat, 2005). Aims: The aim of our study is to evaluate the effectiveness of therapy with ibrutinib and venetoclax in combination for the patients with CLL and CK. Methods: This ambilinear observational study included patients with CLL with high genetic complexity (high-CK), defined as >=5 aberrations or CK (>=3 aberrations) in combination with a 17p deletion (CK+del17p). The first retrospective cohort included patients treated with ibrutinib monotherapy (Imono) to progression or intolerable toxicity since May 2015. The second prospective cohort included patients receiving ibrutinib in combination with venetoclax (IVen) since July 2019. Venetoclax therapy was started at the 3rd month of ibrutinib (from the escalation phase). Combination therapy was continued until a complete response, defined as three consecutive PET-CT-negative and MRD-negative results 3 months apart. If this criterion was not achieved at 24th month of therapy, venetoclax was discontinued and ibrutinib continued indefinitely. Results: Seventy-nine patients are included in the study. Twenty-nine patients in the first cohort and 50 patients in the second cohort. The characteristic is presented in Table. At the current follow-up periods, there were no significant differences in PFS and OS regarding a follow-up period <= 24 months (with the exception of death from COVID-19, since patients were not observed at parallel time intervals). In the group of patients treated with Imono, the majority of patients achieved partial remission or partial remission with lymphocytosis by 12 months. In 21 patients from Iven group, with a median follow-up of 7.4 months, a complete remission was achieved (72.4%);of these, 8 had unmeasurable MRD. Four patients did not complete the escalation period. There was a significant difference in the median MRD response achieved between 3 (log10>10) and 12 (log10<0,1) months in IVen group (p=0,03). In 2 patient from the IVen group progression of the disease was noted. Summary/Conclusion: Combination therapy with ibrutinib and venetoclax is an effective oral regimen for high-risk patients with complex karyotype disorders. PFS in both groups is currently not significantly different, which is obviously due to the short follow-up period. Patients receiving the IVen regimen achieve a significantly better response, which paves the way for allogeneic transplantation in these patients.

B-CELL MALIGNANCIES TREATED WITH TARGETED DRUGS AND SARS-COV-2 INFECTION. A EUROPEAN HEMATOLOGY ASSOCIATION SURVEY (EPICOVIDEHA)

Background: Patients with lymphoproliferatie diseases (LPD) appear particularly ulnerable to SARS-CoV-2 infection, partly because of the effects of the anti-neoplastic regimens (chemotherapy, signaling pathway inhibitors, and monoclonal antibodies) on the immune system. The real impact of COVID-19 on the life expectancy of patients with different subtypes of lymphoma and targeted treatment is still unknown. Aims: The aim of this study is to describe and analyse the outcome of COVID-19 patients with underlying LPD treated with targeted drugs such as monoclonal antibodies (obinutuzumab, ofatumumab, brentuximab, niolumab or pembrolizumab), BTK inhibitors (ibrutinib, acalabrutinib), PI3K inhibitors (idelalisib), BCL2 inhibitors (enetoclax) and IMIDs, (lenalidomide). Methods: The surey was supported by EPICOVIDEHA registry. Adult patients with baseline CLL or non-Hodgkin Lymphoma (NHL) treated with targeted drugs and laboratory-confirmed COVID-19 diagnosed between January 2020 and January 2022 were selected. Results: The study included 368 patients (CLL n=205, 55.7%;NHL n=163, 44.3%) treated with targeted drugs (Table 1). Median follow-up was 70.5 days (range 19-159). Most used targeted drugs were ITKs (51.1%), anti-CD20 other than rituximab (16%), BCL2 inhibitors (7.3%) and lenalidomide (7.9%). Of note, only 16.0% of the patients were accinated with 2 or more doses of accine at the onset of COVID-19. Pulmonary symptoms were present at diagnosis in 244 patients (66.2%). Seere COVID-19 was obsered in 47.8 % patients while 21.7% were admitted to to intensie care unit (ICU), being 55 (26.8%) CLL patients and 25 (15.3%) NHL patients. More comorbidities were reported in patients with seere-critical COVID-19 compared to those with mild- asymptomatic infection (p=0.002). This difference was releant in patients with chronic heart diseases (p=0.005). Oerall, 134 patients (36.4%) died. Primary cause of death was COVID-19 in 92 patients (68.7%), LPD in 14 patients (10.4%), and a combination of both in 28 patients (20.9%).Mortality was 24.2% (89/368) at day 30 and 34.5%(127/368) at day 200. After a Cox multiariable regression age >75 years (p<0.001, HR 1.030), actie malignancy (p=0.011, HR 1.574) and admission to ICU (p<0.00, HR 4.624) were obsered as risk factors. Surial in patients admitted to ICU was 33.7% (LLC 38.1%, NHL 24%). Mortality rate decreased depending on accination status, being 34.2% in not accinated patients, 15.9-18% with one or two doses, decreasing to 9.7% in patients with booster dose (p<0.001). There was no difference in OS in NLH s CLL patients (p=0.344), nor in ITKs s no ITKs treated patients (p=0.987). Additionally, mortality rate dropped from the first semester 2020 (41.3%) to last semester 2021 (25%). Summary/Conclusion: - Our results confirm that patients with B--mallignancies treatted with targeted drugs hae a high risk off seere infection (47.8%) and mortality (36.4%) from COVID-19. - Pressence of comorbidities,, especially heart disease,, is a risk factor for seere COVIID--19 infection in ourr series. - Age >75 years,, actie mallignancy att COVIID--19 onset and ICU admission were mortality risk factors. - COVIID--19 acination was a protectie factor for mortality,, een iin this popullation wiitth humorall immunity impairment. - The learning cure in the management of the infection throughout the pandemiic and the deelopmentt off COVIID--19 treatments showed benefit in this partticullarlly ullnerablle popullation? (Table Presented).

A PHASE 1 STUDY EVALUATING SAFETY AND EFFICACY OF PARSACLISIB IN COMBINATION WITH BENDAMUSTINE + OBINUTUZUMAB IN PATIENTS WITH RELAPSED OR REFRACTORY FOLLICULAR LYMPHOMA (CITADEL-102)

Background: Patients (pts) with follicular lymphoma (FL) generally respond well to first-line CD20-targeted therapies, such as obinutuzumab or rituximab-based regimens. However, many pts relapse and studies suggest that each subsequent relapse is associated with shorter durations of response to the next treatment. Parsaclisib is a potent and highly selective next generation PI3Kδ inhibitor. The combination of bendamustine + obinutuzumab is approved for pts with relapsed/refractory (R/R) FL. We hypothesized that adding parsaclisib may improve clinical benefit with a manageable safety profile in this pt population. Aims: CITADEL-102 (NCT03039114) is an open-label, phase 1, dose-finding study that investigated safety and efficacy of parsaclisib in combination with bendamustine + obinutuzumab in pts with R/R FL following rituximabcontaining regimens. Methods: Pts enrolled were ≥18 years with histologically confirmed CD20-positive FL, R/R to any prior rituximabcontaining regimen, ECOG PS 0-2, ≥1 measurable lesion, and ≤4 prior therapies. Pts received parsaclisib 20 mg orally once daily (QD) for 8 weeks then 20 mg once weekly (QW);bendamustine 90 mg/m2 infusion on days 1 and 2 of cycles 1-6;and obinutuzumab 1000 mg infusion on days 1, 8, and 15 of cycle 1, and day 1 of cycles 2-6, and on every second cycle of cycles 8-30 in pts having complete response/complete metabolic response (CR/CMR), partial response/partial metabolic response (PR/PMR), or stable disease/no metabolic response. Part 1 (safety run-in) used a 3+3 design with dose de-escalation to identify the maximum tolerated dose (MTD) of parsaclisib in combination with bendamustine + obinutuzumab. In Part 2 (dose expansion), the safety and efficacy of this combination were further evaluated. The primary study endpoint was safety and tolerability;secondary endpoints included efficacy outcomes (ORR, DOR, PFS, and OS). Results: A total of 26 pts were enrolled and treated;median (range) age was 65.0 (44-80) years, 25 (96.2%) had ECOG PS ≤1, 11 (42.3%) had ≥2 prior systemic therapies, and 6 (23.1%) had received prior bendamustine. Median (range) parsaclisib exposure was 10.6 (0.4-32.8) months. Main reasons for treatment discontinuation included adverse events (AEs) (8 pts, 30.8%) and progressive disease (6 pts, 23.1%). All pts experienced treatment-emergent AEs (TEAEs);most common any-grade TEAEs (≥10 pts) were pyrexia (53.8%), neutropenia (50%), diarrhea (46.2%), thrombocytopenia, and nausea (each 38.5%). Grade ≥3 TEAEs were experienced by 88.5% of pts;most common grade ≥3 TEAEs (≥2 pts) were neutropenia (34.6%), febrile neutropenia (23.1%), thrombocytopenia (19.2%), ALT and AST increase (each 11.5%), and diarrhea, neutrophil count decreased, and rash maculopapular (each 7.7%). One of 6 evaluable pts in Part 1 had a DLT of grade 4 QTc elongation. The MTD was not reached, and parsaclisib 20 mg QD for 8 weeks then 20 mg QW was the selected dosage for dose expansion in Part 2. Treatment discontinuation due to TEAEs was 30.8%, 7.7%, and 15.4% for parsaclisib, bendamustine, and obinutuzumab, respectively. One fatal TEAE (COVID-19 pneumonia) occurred. ORR (95% CI) as reported by the investigator was 76.9% (56.4-91.0), with 17 pts (65.4%) achieving CR/CMR and 3 pts (11.5%) achieving PR/PMR as the best overall response. Median DOR, PFS, and OS were not reached. Summary/Conclusion: Parsaclisib in combination with bendamustine + obinutuzumab appears to have a manageable safety profile and demonstrated promising efficacy in pts with R/R FL.

EFFICACY AND SAFETY OF IMMUNOCHEMOTHERAPY IN TREATMENT OF FOLLICULAR NONHODGKIN'S LYMPHOMA DURING COVID-19 PANDEMIC: A STUDY OF KROHEM, THE CROATIAN COOPERATIVE GROUP FOR HEMATOLOGIC DISEASES

Background: Follicular lymphoma (FL) is a systemic neoplasm of the lymphoid tissue arising from B cell proliferation. The novel monoclonal anti-CD20 antibody obinutuzumab in combination with chemotherapy has been widely accepted as the first choice in front line treatment of FL. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), responsible for coronavirus disease 2019 (COVID-19) is causing increased mortality among patients with lymphoproliferative disorders compared with the general population. Furthermore, there are some concerns in terms of morbidity and mortality for patients with FL because of their immunocompromised status induced by recent exposure to cytotoxic chemotherapy, especially bendamustine and anti-CD20. Aims: To investigate efficacy and safety of immunochemotherapy protocols for patients with newly diagnosed FL during COVID-19 pandemic. Methods: We retrospectively investigated medical data of all patients with newly diagnosed FL grade 1, 2 or 3A from Croatian hematologic registry in period from April 2019 to March 2021. Only patients which required systemic treatment were included in the analysis. All patients received obinutuzumab (G) in combination with either CHOP, bendamustine (B) or CVP chemotherapy protocol. Treatment response was evaluated using international lymphoma response criteria. Results: We analyzed a total of 114 FL patients treated with G-chemotherapy. Mean age was 62.4 ±10.5 years. Majority of patients were female (71/114 (62.3%)). FL grade I was present in 45/114 (39.5%), grade II in 28/114 (24.6%), grade III in 27/114 (23.7%) and not specified (but not IIIB) in 14/114 (12.3%) patients. A total of 61/114 (53.5%) patients were treated with G-B, 49/114 (43%) with G-CHOP and 4/114 (3.5%) with G-CVP immunochemotherapy. Similar rates of adverse events were observed in patients treated with G-CHOP and G-B Median follow up was 17 months. Overall response rate was 94%, complete remission (CR) in 68% and partial remission (PR) in 25% of patients. Median overall survival (OS) and progression free survival (PFS) were not reached with 12-months rates of 94% and 92%, respectively. Patients treated with G-CHOP had statistically significantly superior OS and PFS compared to patients treated with G-B (P=0.002 and P=0.006, respectively, Fig. 1). More favorable survival course associated with G-CHOP in comparison to G-B persisted in multivariate analysis (P=0,026, HR=15,12) after adjustment for age, sex, FLIPI grade and SARS-CoV-2 infection. Total of 12 patients died during the follow up and COVID-19 was cause of death in 5 patients. During the follow-up SARS-CoV-2 infection was diagnosed in 20/114 (17,5%) patients with overall mortality rate of 25%. All of the 7 patients treated with GCHOP recovered from SARS-CoV-2 infection and mortality rate in infected group of patients treated with G-B was 33% (4/12 patients). Image: Summary/Conclusion: Increased COVID-19 mortality in patients with lymphoproliferative disorders was observed in this study. Our group of patients had reduced OS and PFS compared to the GALLIUM trial and SARS-CoV-2 infection was the most pronounced risk factor for death. Even though in some studies bendamustine has shown to be less toxic and more effective than CHOP in FL, there are some important pandemic aspects that must be considered. Bendamustine exposure seems to be associated with worse outcome in case of the infection with SARS-CoV-2. These intriguing differences could play important role in treatment approach in COVID-19 pandemic. Future studies investigating hematological malignancies in COVID-19 pandemic are warranted.

OUTCOME OF FOLLICULAR LYMPHOMA PATIENTS IN MAINTENANCE TREATMENT WITH ANTICD20 MONOCLONAL ANTIBODIES IN SARS-COV2 ERA: RESULTS FROM A MULTICENTER, RETROSPECTIVEPROSPECTIVE ITALIAN STUDY

Background: Maintenance in FL patients (pts) improves progression free survival (PFS). SARS-Cov2 pandemic posed unique challenges for immunocompromised pts. Aims: The aim is to evaluate the outcome of FL pts in maintenance with antiCD20-MoAb during SARS-Cov2 pandemic and how suspension of therapy affected lymphoma outcome and the risk of SARS-Cov2 infection and its morbidity and mortality. Methods: This is an observational, multicenter, retrospective and prospective study. Results: A total of 420 from 18 Italian Hematological Centers were included in the analysis. Median age was 62 years old (range 27-91 years), 216 pts (51%) were male. Main clinical characteristics of the population were: histological grade 1-2 vs 3A in 288 (69%) vs 109 (26%), while not valuable in 23 (5%) pts;limited I-II vs advanced III-IV stage in 57 (14%) vs 361 (86%) pts, not reported in 2 cases. FLIPI score was low vs intermediate vs high in 71 (17%) vs 151 (36%) vs 192 (46%) patients, respectively, not valuable in 6 cases. All 420 patients included were in maintenance treatment with antiCD20 MoAb at the time of the onset of SARS-Cov2 pandemic (March 2020): 333 (79%) pts were receiving maintenance after a first line, while 87 (21%) after a second line. 342 (81%) pts were receiving Rituximab, while 75 (18%) Obinutuzumab, 3 patients did not start the planned maintenance because of pandemic spread. Status of disease after induction was complete remission (CR) in 374 (89%), partial response (PR) in 41 (10%), progressive disease (PD) in 1, not evaluated in 4 pts, respectively. At the end of maintenance was CR in 265 (63%), PR in 19 (4%), stable disease (SD) in one and PD in 14 (3%) patients, respectively, maintenance is stiil ongoing in 121 (29%) pts. Because of SARS-Cov2 pandemic from March 2020 consequences on maintenance treatment were: temporary suspension in 122 (29%), definitively interruption in123 (29%), no modification in 175 (42%) of pts, respectively. Median number of maintenance treatment administered at the time of SARS-Cov2 pandemic onset was 2 (range 1-12), median number of courses administered at the time of analysis was 8 (range 0-12), in patients who modified treatment because of pandemic median number of performed courses was 7 (range 0-11) and median number of lost cycles were 2 (range 1-12). Pts were divided into two groups according to type of approach to maintenance during pandemic: pts who interrupted maintenance (temporary or definitively): groups A (245 (58%) pts) vs pts who did not modified maintenance: group B (175 (42%) pts). No differences in clinical characteristics, type of therapy and response were observed between the two groups. 29(7%) relapses were observed: 16 (7%) vs 13 (7%) in group A vs B, respectively. 70 (17%) pts experienced SARS-Cov2 positivity: 47 (19%) vs 23 (13%) in group A vs B, respectively. 53 (76%) pts had symptomatic COVID syndrome and 43 (61%) were hospitalized, with no differences between the two groups. Anti-SARS-Cov2 vaccine was administered in 349 patients, serology assessment was done in 46% of cases, showing 21 (13%) reactive vs 138 (87%) not reactive pts, with no differences between the two groups. 21 (30%) pts died because of COVID: 9 (19%) vs 12 (52%) in groups A vs B, respectively. Summary/Conclusion: Suspension of maintenance treatment during SARS-Cov2 pandemic did not show a protection in terms of SARS-Cov2 positivity and morbidity. A trend in lower mortality is suggested. No differences in terms of relapse rate were observed, but longer follow up is needed.

TIME-LIMITED TREATMENT WITH ACALABRUTINIB PLUS OBINOTUZUMAB IN TREATMENT-NAÏVE CHRONIC LYMPHOCYTIC LEUKEMIA PATIENTS INDUCES DEEP REMISSIONS: EARLY RESULTS OF AN ONGOING PHASE 2 TRIAL

Background: The Bruton's tyrosine kinase (BTK) inhibitor acalabrutinib is approved for treatment of chronic lymphocytic leukemia(CLL). Acalabrutinib induces durable remissions in most CLL patients, which mostly are partial remissions (PR), and therefore treatment typically is given as long-term monotherapy. As a potential alternative we developed a time-limited regimen, combining acalabrutinib with obinutuzumab. Aims: Here, we report early results from 14 treatment-naïve patients with CLL who enrolled in this ongoing phase 2 trial (NCT04505254) since September, 2020 at MD Anderson Cancer Center. Methods: Patients and Study Design: Treatment-naïve CLL patients requiring therapy as per iwCLL criteria receive acalabrutinib 100 mg orally twice a day for 24 cycles, combined with monthly obinotuzumab for 6 doses, starting in cycle 3. The first dose of obinutuzumab is divided into 100 mg on day 1 and 900 mg on day 2 of cycle 3;1000 mg are given during subsequent cycles (cycles 4-8). Patients who do not achieve a complete remission (CR) after cycle 8 can receive an additional 6 monthly doses of obinotuzumab during cycles 9 -14. Treatment is discontinued after 24 cycles, and patients will be monitored. The primary objective is to determine the durability of remissions after treatment discontinuation, secondary objectives are to determine clinical and laboratory characteristics that predict for early versus late relapse after time-limited therapy. Results: The median age of the patients is 70 yrs (range, 40 -83 yrs), 14% had del17p or TP53 mutation, 43% had an unmutated IgHV and 71% advance stage disease (RAI stage III and IV). The median baseline absolute lymphocyte count (ALC) and b2 microglobulin at start of therapy were 39.2x109/L (range: 7.1 - 188.4 x 109/L) and 4.2 mg/L (range: 2.2 - 7.9 mg/L), respectively. After a median follow-up of 7 months (2 - 16 months), 13 (93%) of patients remain on study;one patient died (7%) due from complications from a presumed bacterial (COVID19-negative) pneumonia after 2 months on therapy. The estimated one-year PFS and OS for the cohort is 92.8 %. Seven patients were evaluable for response assessment after 8 months of therapy. No patient has yet discontinued therapy. All patients achieved a PR (one patient with undetectable minimal residual disease/U-MRD in the bone marrow), accounting for an overall responsonse rate of 100%. The median levels of bone marrow infiltration by CLL cells, quantified by flow cytometry, declined from 83.6% (range: 54.3 - 94.0 %) at baseline to 4.1% (range, 0.0 - 63.3%, n=7, p<0.05, see figure) after 6 cycles of combination treatment. Sixty-four percent of patients completed all doses of obinotuzumab, 50% requiered a dose reduction of acalabrutinib to 100 mg per day due to adverse events (AE). Grade 33 AE were observed in 4 patients (29%), which included decreased neutrophil counts (n=2), syncope (n=1), and grade 5 lung infection (COVID19 not detected, n=1). The most frequently reported non-serious related AE (3 2 patients) were anemia (n=5 [36%]), decreased platelets counts (n=3 [21%]), bruising (n=3 [21%]), limbs edema (n=2 [15%]) and headache (n=2 [15%]). All these events were grade 1. Importantly, no bleeding or atrial fibrillation events were observed. 3285 (Figure Presented ) Summary/Conclusion: Our preliminary data indicate that combination therapy of acalabrutinib plus obinotuzumab induces remissions with a major reduction in bone marrow disease after 6 months of combination therapy. Longer treatment and follow-up is warranted to determine the durability of responses after therapy discontinuation.

A Biphasic COVID-19 Clinical Course in Anti-CD20 Treated Patients: Case Series and Review of the Literature.

We describe four cases of COVID-19 infection during the Omicron wave, in patients treated with anti-CD20 monoclonal antibodies. All cases follow a similar biphasic clinical course consisting of respiratory deterioration, which occurred a few weeks after convalescence from initial mild to asymptomatic infection. Possible explanations are discussed. LEARNING POINTS: Four cases of COVID-19 infection in anti-CD20 treated patients are described.These cases display a unique biphasic course that was previously undescribed: respiratory deterioration weeks after convalescence.Awareness of such a course and rapid utilisation of bronchoalveolar lavage will lead to quicker diagnosis and more timely, appropriate treatment.

Clinical impact of SARS-CoV-2 delta variant infection in tumor patients and the impact of vaccination on different cancer treatment regimens

Background: Data on SARS-CoV-2 infections in oncological patients in the outpatient settings are scarce. Methods: During the spread of the delta variant between April 2021 and September 2021, a total of 10.677 patients were tested for SARS-CoV-2 infection by RT-qPCR in seven outpatient clinics in Bavaria, Germany. Results: Within the tested patient cohort, 4.960 patients (46.5%) suffered from a malignant disease (74% solid tumors and 26% malignant hematological diseases). This group was compared with 5.717 patients (53.5%) without a malignant disease (33.1% with other hematological diseases and 66.9% patients without a hematological or oncological disease). During the observation period, 119 (2.4%) patients with malignancies were tested positive (88 patients with solid tumors;31 patients with malignant hematological diseases) compared to 115 positive patients (2.0%) in the control group. 32 of 119 positively tested patients (26.9%) suffering from malignant disease required hospitalization and 9/32 patients (28.1%) died during the clinical course. Conclusions: These observations are in clear contrast to data from patients we evaluated during the pre-delta variants period between 15 and 26 April 2020 in the same seven outpatient clinics. In this period, a total of 1.227 patients were tested for SARS-CoV-2 by RT-qPCR. 78/1227 patients (6.3%) were tested positive in RT-qPCR and most showed mild symptoms of infection. None of the SARS-CoV-2 infected patients died. These data were analyzed when no vaccination was available. These data were evaluated during a period where no vaccine was available. Vaccination of patients with malignancies with BiontechPfizer's mRNA vaccines was started in April 2021. The response to the vaccine was tested by an antibody assay (Elecsys Anti-SARS-CoV-2 S-immunoassay, Roche) at the earliest four weeks after the second vaccination. To assess the response, we compared five patient cohorts: Patients who received (i) B cell depleting antibodies, (ii) checkpoint inhibitors (ICI), (iii) chemotherapy, or (iv) tyrosin kinase inhibitors (TKIs), and (v) healthy controls. The patients treated with ICI or TKI showed a comparable vaccination response to the healthy patients, while patients receiving Rituximab/Obinutuzumab showed no significant humoral vaccination response at all. The more severe disease course of patients infected by the SARS-CoV-2 delta variant compared to the initial waves of infections strongly underline the importance of vaccination in cancer patients.

Outcome of follicular lymphoma (FL) patients in maintenance with antiCD20 monoclonal antibodies (MoAb) in SARS-Cov2 era

Background: Maintenance in FL patients (pts) improves progression free survival (PFS). SARS-Cov2 pandemic posed unique challenges for immunocompromised pts. Methods: This is an observational, multicenter, retrospective and prospective study. The aim is to evaluate the outcome of FL pts in maintenance with antiCD20-MoAb during SARS-Cov2 pandemic and how suspension of therapy affected lymphoma outcome and the risk of SARS-Cov2 infection and its morbidity and mortality. Results: 420 pts from 18 Italian Centers were included. Median age was 62 years old (range 27-91), 216 pts (51%) were male. Main clinical characteristics were: histological grade 1-2 vs 3A vs not valuable in 288 (69%) vs 109 (26%) vs 23 (5%), respectively;advanced stage in 361 (86%), high FLIPI score in 192 (46%) pts. All 420 pts were in antiCD20-MoAb maintenance at the time of SARS-Cov2 pandemic onset (March 2020): 333 (79%) were receiving maintenance after a first line, while 87 (21%) after a second line. 342 (81%) pts were receiving Rituximab, while 75 (18%) Obinutuzumab, 3 pts did not start the planned maintenance. Status of disease after induction was complete remission (CR) in 374 (89%), partial response (PR) in 41 (10%), progressive disease (PD) in 1, not evaluated in 4 patients, respectively. At the end of maintenance was CR in 265 (63%), PR in 19 (4%), stable disease (SD) in one and PD in 14 (3%) pts, maintenance is ongoing in 121 (29%) pts. Because of SARS-Cov2 pandemic maintenance treatment was temporary suspended in 122 (29%), definitively interrupted in123 (29%), not changed in 175 (42%). Median number of maintenance treatment administered at March 2020 was 2 (range 1-12), in pts who modified treatment median number of performed vs lost courses was 7 (range 0-11) vs 2 (range 1-12). Patients were divided into two groups according to the approach to maintenance during pandemic: pts who interrupted maintenance (temporary or definitively): groups A (245 (58%) cases) vs pts who did not modified maintenance: group B (175 (42%)). No differences in clinical characteristics, type of therapy and response were observed between the two groups. 29(7%) relapses were observed: 16 (7%) vs 13 (7%) in group A vs B. 70 (17%) pts experienced SARS-Cov2 positivity: 47 (19%) vs 23 (13%) in group A vs B. 53 (76%) pts had symptomatic COVID and 43 (61%) were hospitalized, with no differences between the two groups. Anti-SARS-Cov2 vaccine was administered in 349 patients, serology assessment was done in 46% of cases, showing 21 (13%) reactive vs 138 (87%) not reactive patients, with no differences between the two groups. 21 (30%) pts died because of COVID: 9 (19%) vs 12 (52%) in groups A vs B. Conclusions: Suspension of maintenance during SARS-Cov2 pandemic did not show a protection in terms of SARS-Cov2 positivity and morbidity. A trend in lower mortality is suggested. No differences in terms of relapse rate were observed, but longer follow up is needed.