Plasma with high titers of anti-SARS-Cov2 antibodies improves outcome of COVID-19 in patients with hematological malignancy and cancer in a randomized controlled trial

Background. Patients with hematological malignancy or other cancers as well as immunosuppression bear a high risk for severe COVID-19. Monoclonal antibodies (mAb) are efficient at early stages of the disease but may lose potency with new variants. Trials on plasma from convalescent donors in unselected patients have not shown clinical benefit. No randomized trials focussing on patients with underlying disease have been published. Methods. We conducted an open-label, multicenter, randomized controlled trial to evaluate efficacy of plasma (CVP - convalescent or after vaccination) in patients with COVID-19 at high risk for adverse outcome in Germany. We assessed the effect of high-titer CVP (2 units from different donors, 238-337 ml each, on subsequent days). Patients with hematological or other malignancy (group 1), immunosuppression (group 2), age >50 and <=75 years and lymphopenia and/or high D-dimers (group 3) or age >75 years (group 4) who were hospitalized with confirmed SARS-CoV-2 infection and with an oxygen saturation <=94% were included. Primary outcome measure was time to clinical improvement on a seven-point ordinal scale, secondary outcome was mortality (Janssen et al. Trials 2020 Oct 6;21(1):828). Results. Overall, 133 patients were randomized, 68 received CVP with an additional 10 patients as a crossover on day 10. Median age (range) was 68 years (39-95) in the CVP group and 70 (38-90) in controls. For the entire cohort, no significant difference was seen in time to improvement (median days: CVP 12.5 vs. control 18;HR 1.24 (95% confidence interval (CI) 0.83-1.85), p=0.29). Subgroup analysis (group 1+2) revealed shortened time to improvement (median days CVP 13 vs. control 32;HR 2.03 (95%CI 1.17-3.6), p=0.01) and mortality was reduced (mortality CVP n=6 (18%) vs. control n=10 (29%). No significant differences in time to improvement were observed in group 3 or 4 (HR 0.72 (95%CI 0.41-1.28), p=0.26). No relevant adverse events were observed. Conclusion. CVP improves time to clinical improvement and mortality for COVID-19 patients with underlying hematological disease/cancer or other reasons of impaired immune response. Even with new variants, high-titer CVP may offer a widely available and inexpensive therapy option in high-risk groups. Funding. BMBF FKZ 01KI20152;EudraCT 2020-001632-10.

Neutralization of the SARS-CoV-2 Delta and Omicron Variants in Previous Non-Responder Kidney Transplant Recipients After Short-Term Withdrawal of Mycophenolic Acid

Background: Response to COVID-19 vaccination is significantly impaired in kidney transplant recipients (KTR) even after three doses of an mRNA vaccine. Adaptive immunization strategies are urgently needed to ultimately protect these patients from COVID-19. Method(s): We determined the effect of an additional mRNA-1273 vaccine dose in 76 non-responder KTR with at least 3 previous vaccine doses. In 43 KTR with triple immunosuppressive therapy including a calcineurin inhibitor (CNI), mycophenolic acid (MPA), and corticosteroids (CS), MPA was withdrawn to investigate the effect of short-term MPA withdrawal on COVID-19 vaccine immunogenicity. Seroconversion was determined four weeks after vaccination. In addition, neutralization of the delta and omicron variants was determined using a live-virus assay. In patients with temporary MPA withdrawal, donor-specific antibodies (DSA) and donor-derived cell-free DNA (dd-cfDNA) were monitored before MPA withdrawal and at follow-up. Result(s): After vaccination, 24/69 (35%) KTR showed anti-spike S1 IgG antibodies above the predefined cut-off, excluding 7 breakthrough infections that occurred during follow-up. SARS-CoV-2 specific antibodies were significantly higher in patients where MPA was withdrawn (Figure 1A). Neutralization of the delta variant was significantly better compared to neutralization of the omicron variant (Figure 1B). Higher SARSCoV-2-specific antibodies were associated with better in-vitro neutralization of the delta and omicron variants (Figure 1C). In KTR with MPA withdrawal, no significant changes in S-creatinine, proteinuria or dd-cfDNA were observed. No acute rejection episode occurred during short-term follow-up. However, resurgence of pre-existing DSA was observed in 7 patients and the development of de novo DSA in one patient. Conclusion(s): MPA withdrawal seems reasonable to increase immunogenicity of SARS-CoV-2 vaccination. For safety reasons, this may only be offered to patients without current or previous DSA.

A RANDOMIZED CONTROLLED CLINICAL TRIAL DEMONSTRATES THAT PLASMA FROM CONVALESCENT AND VACCINATED DONORS IMPROVES OUTCOME OF COVID-19 IN PATIENTS WITH HEMATOLOGICAL DISEASE, CANCER OR IMMUNOSUPPRESSION

Background: Therapy options are limited for COVID-19 patients with hematological disease, cancer, immunosuppression or adanced age. Een though no benefit was obsered for conalescent plasma in unselected patients with COVID-19, retrospectie data suggest that it could be effectie in patients unable to mount a sufficient immune response upon SARS-CoV-2 infection. Plasma from accinated donors has not been systematically assessed for COVID-19 treatment. Aims: We conducted a randomized clinical trial to address plasma efficacy in patients at high risk for an aderse outcome. Methods: COVID-19 patients with confirmed SARS-CoV-2 infections and oxygen saturation <=94% were randomized (NCT05200754). Patients receied conalescent or accinated SARS-CoV-2 plasma in two bags (238 - 337 ml plasma each) from different donors on day 1 and 2 (PLASMA) or standard of care (CONTROL). Randomization was stratified according to four clinical patient groups, hematological/solid cancer (group-1), treatment or disease associated immunosuppression (group 2), high risk disease by standard parameters (group-3) or age >=75 years (group-4). Mechanically entilated patients were not eligible. Plasma was obtained from donors with high leel neutralizing actiity (titer >=1:80) either after SARS-CoV-2 infection (conalescent) or after accination with at least two doses of mRNA accines (accinated). Crossoer for the control group was allowed at day 10. The primary endpoint was time to improement as two points on a seen-point ordinal scale or lie discharge from the Hospital (IMPROVEMENT) with prespecified analyses of subgroups (Janssen M, et al. Trials 2020 Oct 6;21(1):828). Results: A total of 133 patients were randomized with 68 receiing PLASMA with a median age of 68 years (range 36-95) or CONTROL (n=65, of which n=10 (15.4%) crossed oer at day 10) with a median age of 70 years (range 38-90). The distribution of the four predefined groups was group-1, n=53;group-2, n=18;group-3, n=35;and group-4, n=27. The intention to treat analysis reealed a non-significant shorter time to IMPROVEMENT for patients in PLASMA (median 12.5 days, 95%-CI [10;16]) compared to patients in CONTROL (median 18 days, 95%-CI [11;28] ), hazard ratio 1.24, 95% confidence interal [0.83;1.85], p=0.29). Oerall, 27 patients died (PLASMA, n=12;CONTROL, n=15;p=0.80). Predefined subgroup analysis reealed a clinically significant benefit in patients with hematological malignancies, other cancers or immunosuppression (group-1, group-2, n=71). With a median time to improement of 13 days (95%-CI [9;19]) for PLASMA and 32 days (95%-CI [17;57]) for CONTROL(HR 2.03, 95%-CI [1.17;3.6], p=0.01). A sensitiity analysis reealed that IMPROVEMENT appeared to be seen een earlier with accinated (median 10 days, 95%-CI [8;14]) compared to conalescent SARS-CoV-2 plasma (median 13 days, 95%-CI [6;38]) and CONTROL. Within group-1 and group-2, six patients in PLASMA (18.2%) and 10 in CONTROL (28.6%) died. No significant differences in improement were obsered in group-3 and group-4 with a HR of 0.72 (95%-CI [0.41;1.28], p=0.26). Within group-3 and group-4, six patients in PLASMA (18.8%) and fie in CONTROL (16.7%) died. No preiously unknown side effects of plasma therapy emerged within the trial. Summary/Conclusion: Plasma from conalescent and particularly accinated donors improed outcome of COVID-19 patients with an underlying hematological disease /cancer or other reasons of impaired immune response. Plasma did not improe outcome in immune-competent patients with other risk factors and/or older age. (Figure Presented).

Cobicistat synergizes with remdesevir to suppress SARS-CoV-2 replication in vitro

Background: The ongoing SARS-CoV-2 pandemic poses an urgent need to identify novel drug treatments that are effective, well tolerated and quickly translatable to a clinical setting. Methods: In-silico binding modes were predicted by molecular docking. The Bavpat1/2020 SARS-CoV-2 isolate was used to infect Calu-3, T84, Vero E6 cells and a primary colon organoid at MOIs of 0.05 or 0.5. Supernatant and intracellular SARS-CoV-2 RNA was quantified by RT-qPCR or immunofluorescence (IF). The activity of the main protease of SARS-CoV-2 (3CLpro) was measured by FRET assay. Viral protein expression was assessed by western blot. Syncytia formation was determined by IF in cells expressing the spike protein. Cell viability was determined by MTT and crystal violet staining. Synergism scores were calculated using the SynergyFinder web-tool. Results: In-silico docking using a library of FDA-approved drugs highlighted cobicistat as candidate inhibitor of SARS-CoV-2 3CLPro. Experiments using two different viral MOIs in three different cell lines proved that cobicistat inhibits SARS-CoV-2 replication at non-toxic, low micromolar concentrations (IC50 0.6-9μM;CC50 39-52 μM) (Fig 1A). However, cobicistat did not inhibit 3CLpro activity in FRET assay, while western blot analysis suggested that cobicistat impacts on spike glycoprotein levels/processing. Accordingly, cobicistat decreased syncytia formation in spike-expressing Vero E6 cells. The range of in-vitro antiviral concentrations of cobicistat was compatible with plasma levels reachable in mice and humans, but above those achieved through standard dosages used to boost HIV-1 protease inhibitors, in line with the failure of trials testing cobicistat-boosted darunavir on SARS-CoV-2 patients. As the booster activity of cobicistat is exerted through inhibition of Cytochrome P4503A (CYP3A) and P-glycoprotein P-gp (known also as multidrug resistance MDR1), we combined it with remdesivir, which is a putative CYP3A and P-gp substrate. The drug combination was able to synergistically rescue the viability of infected cells to levels comparable to uninfected controls and to almost entirely abrogate viral replication in two cell lines and a primary colon organoid (Figure 1B-D). Conclusion: Cobicistat and remdesivir synergistically inhibit SARS-CoV-2 replication and cytopathic effects. Cobicistat can form the backbone of combination treatments due to its dual activity as direct antiviral and pharmacoenhancer.

From Multiplex Serology to Serolomics-A Novel Approach to the Antibody Response against the SARS-CoV-2 Proteome

The emerging SARS-CoV-2 pandemic entails an urgent need for specific and sensitive high-throughput serological assays to assess SARS-CoV-2 epidemiology. We, therefore, aimed at developing a fluorescent-bead based SARS-CoV-2 multiplex serology assay for detection of antibody responses to the SARS-CoV-2 proteome. Proteins of the SARS-CoV-2 proteome and protein N of SARS-CoV-1 and common cold Coronaviruses (ccCoVs) were recombinantly expressed in E. coli or HEK293 cells. Assay performance was assessed in a COVID-19 case cohort (n = 48 hospitalized patients from Heidelberg) as well as n = 85 age- and sex-matched pre-pandemic controls from the ESTHER study. Assay validation included comparison with home-made immunofluorescence and commercial enzyme-linked immunosorbent (ELISA) assays. A sensitivity of 100% (95% CI: 86-100%) was achieved in COVID-19 patients 14 days post symptom onset with dual sero-positivity to SARS-CoV-2 N and the receptor-binding domain of the spike protein. The specificity obtained with this algorithm was 100% (95% CI: 96-100%). Antibody responses to ccCoVs N were abundantly high and did not correlate with those to SARS-CoV-2 N. Inclusion of additional SARS-CoV-2 proteins as well as separate assessment of immunoglobulin (Ig) classes M, A, and G allowed for explorative analyses regarding disease progression and course of antibody response. This newly developed SARS-CoV-2 multiplex serology assay achieved high sensitivity and specificity to determine SARS-CoV-2 sero-positivity. Its high throughput ability allows epidemiologic SARS-CoV-2 research in large population-based studies. Inclusion of additional pathogens into the panel as well as separate assessment of Ig isotypes will furthermore allow addressing research questions beyond SARS-CoV-2 sero-prevalence.