P1531: tixagevimab-cilgavimab therapy in the prevention of sars-cov2 infection in non-hodgkin-b lymphomas and hodgkin lymphomas under treatment: our experience

Topic: 30. Infections in hematology (incl. supportive care/therapy) Background: Patients with B-cell malignancies who become infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are at an increased risk of morbidity and mortality due to advanced age, use of B-cell-depleting therapies, and immunodeficiency. Despite development of COVID-19 messenger RNA vaccines, the majority of patients with B-cell malignancies fail to develop anti-SARS-CoV-2 spike antibodies in response to vaccination, and mortality rates secondary to COVID-19 infection over 10% have been reported. Preexposure prophylaxis with tixagevimab-cilgavimab may be an alternative strategy to decrease the incidence or severity of COVID-19 for patients with NHL B-cell malignancies. Tixagevimab-cilgavimab is a monoclonal antibody (MoAb) that inhibits attachment of the SARS-CoV-2 spike protein to the surface of cells, thereby preventing viral entry and infection by the COVID-19 virus. Tixagevimabcilgavimab was authorized based on results of the phase III PROVENT study, which demonstrated a breakthrough infection rate of 0.5% in unvaccinated adults at an increased risk of inadequate response or exposure to COVID-19. However, only 7% of patients had cancer or a history of cancer, and 3% were actively receiving immunosuppressive therapy. Aims: The aim of the study is to evaluate the impact of prevention with texagevimab-cilgavimab in a cohort of patients, observed in our Division, with non-Hodgin B lymphoma or Hodgkin’s lymphoma under treatment or who had finished treatment in the previous 6 months. Methods: From 1 July 2022 to 31 January 2023, we evaluated 101 pts 48 F and 53 M with a median age of 65 years (range 16-91 years) a cohort of patients (pts), who started or were under specific treatment, to whom we performed tixagevimab-cilgavimab in the prevention of SARS-CoV-2. 95% of pts had previously received the recommended vaccine doses, median 2 (range 2-4 doses). 12HD; 88 NHLs; 1 HCL. In 33 (33%) pts has been effectued before the start of treatment and 68 (67%) during treatment. 47 (46.5%) were on induction treatment, 47 (46.5%) on maintenance therapy with anti-CD20 or imbruvica or venetoclax and 7 (7%) had finished treatment within the previous 3 months. Results: Of the 101 pts, 21% were developed covid infection during observation: 12 M and 9 F median age 65 years (range 21-83 years) 2 HD and 19 NHL. 14 pts were in maintenance therapy (9 rituximab; 4 Obinutuzumab and 1 pc ibrutinib + Rituximab) and 7 in induction treatment (2 AdAVD;1 G-CVP;2 R-MACOP-B;1 R-BAC and 1 R-COMP). 12 pts (57%) had mild symptoms (median age 55 years) while 9 (43%) had severe symptoms who has required hospitalization (median age 75 years). 6 patients (28.5%),with a median age of 75 years, died of COVID. In 9/21 pts (43%) the treatment was not interrupted (4 patients in induction therapy and 5 patients in maintenance therapy) all with mild COVID symptoms, no COVID-related complication was documented in these patient. 4 pts regularly terminated the treatment while 5 are still in treatment. Of the patients who died, 1 had finished induction therapy (R-BAC) while 5 were on maintenance therapy (3 rituximab and 2 obinutuzumab). Summary/Conclusion:From our experience, prevention therapy does not seem to have changed the incidence and prognosis of the SARS-COV2 infection, certainly variables that seem to influence are age (75 vs 55 years) and the total IgG value (patients with severe symptoms had a median IgG of 415 mg/dl vs 817 mg/dl in patients with mildly symptomatic COVID), further in patients with mild symptoms the COVID infection did not interfere with the continuation of the specific treatment, we do not know if in these cases it could to helping the preventive therapy. A larger cohort of patients is needed to consolidate or confirm the data of our observation. Keywords: Prophylaxis, NHL, COVID-19