1590P Treatment outcomes and antibody immunity to SARS-CoV-2 in patients with hematological malignancies

Abstract

Since SARS-CoV-2 infection heavily affects vulnerable populations including those with immune suppression, it is of special value to study clinical course, treatment outcomes, and immunity in patients (pts) with hematological (hem) malignancies. CHRONOS19 is an ongoing observational study in adult pts (≥18 years) with hem diseases (malignant or non-malignant) and COVID-19 in Russia. This web-based registry collected de-identified data from 15 centers all over the country at 30, 90, and 180 days after lab-confirmed or suspected (based on CT and/or clinical symptoms) COVID-19 diagnosis. The primary endpoint was 30-day all-cause mortality. As of data cut-off on April 14, 2021, 626 pts were enrolled in the study; 562 were eligible for primary endpoint assessment, n (%): M/F 271 (48%) / 291 (52%), median age 56 [18-90] years, malignant disease in 516 (92%) pts, among them induction phase / relapse or refractory / remission / NA in 180 (35%) / 120 (23%) / 187 (36%) / 29 (6%) pts. Thirty-day all-cause mortality in pts with hem malignancies was 19%; 83% of deaths were due to COVID-19 complications. No increase of hem disease relapse rate after COVID-19 was observed at Day 90 or Day 180, although 180-day data was still not mature at the time of analysis. IgG to SARS-CoV-2 was detected in 84% of pts with hem malignancies (167/199). The highest rate of detected antibody immunity was found in pts with chronic myeloproliferative neoplasms (100%; 13/13), HL (100%; 12/12), and multiple myeloma (97%; 34/35), the lowest – in pts with CLL (62%; 8/13) and NHL (60%; 6/10 and 56%; 10/18 for low-grade and high-grade lymphoma, respectively). igG detection rate in CD20+ lymphoma (60%) was significantly lower than in HL or T-cell lymphoma (p=0.004). Pts with ECOG 0-2 throughout the disease had a high rate of antibody immunity (90%; 104/116) vs. those with ECOG 3-4 at the time of COVID-19 diagnosis (77.5%; 31/40) or with worsening of ECOG to 3-4 during the disease (78%; 36/46). Five cases of SARS-CoV-2 re-infection were described. Pts with hem malignancies and COVID-19 have higher mortality than the general population. Low post-disease antibody immunity to SARS-CoV-2 and cases of re-infection may justify vaccination of these pts and warrant further research.