POS0261 TIME SINCE LAST RITUXIMAB TREATMENT IS ESSENTIAL FOR DEVELOPING A HUMORAL RESPONSE TO THE COVID-19 MRNA VACCINE IN PATIENTS WITH RHEUMATIC DISEASES

Background

Concerns about Rituximab (RTX) treatment and potentially inadequate vaccine response were aired early in the pandemic, and initial data seem to support this concern (1). So far, studies regarding rheumatic patients and the COVID-19 vaccines have included a relatively small number of patients receiving rituximab.

Objectives

We aimed to investigate if patients with rheumatic diseases treated with RTX raise a serological response towards the COVID-19 mRNA vaccines and to elucidate the influence of time since the last dose RTX before vaccination on this response.

Methods

We included 201 patients followed at the Department of Rheumatology, Aarhus University Hospital. All had been treated with RTX in the period 2017-2021, and had finished a two-dose COVID-19 mRNA vaccination. All patients and 44 blood donors had total antibodies against SARS-CoV2 spike protein measured. Univariate and multivariate logistic regression were used.

Results

Patients were predominantly female (67%) with a median age of 62 years. The most frequent diagnosis was ANCA-associated vasculitis (32%), rheumatoid arthritis (31%), and myositis (14%), and 97% had the Pfizer/Biontic vaccine. Median number of RTX infusions were 5 (IQR 2-8), with a cumulative dose of 4g (2-8), and 72% had received RTX within the last 15 months. Prednisone was used by 43%, followed by methotrexate (25%), hydroxychloroquine (11%) and azathioprine (10%).

We observed a time-dependent increase in antibody response as the interval from the last RTX treatment to vaccination increased (Table 1). Only 17.3% of patients developed a detectable antibody response after receiving their vaccination 6 months or less after their previous RTX treatment (Figure 1). Positive antibody response increased to 66.7% in patients who had RTX 9-12 months before vaccination. Neither cumulative treatment time nor cumulative RTX dose seemed to influence the serological response to the vaccine (Table 1). Thus, even in patients who have received RTX for a substantial time, expanding time-since-last-RTX treatment could prove beneficial for increasing the chance of a serological response. We further found that “months between last Rtx and vaccination”, prednisone and azathioprine treatment were alle negatively associated with antibody response in a multivariate logistic regression analysis(Table 1). All blood donors (100%) had detectable antibodies after vaccination.

Table 1.

Logistic regression analysis with precense of SARS-CoV-2 antibodies after mRNA vaccination as dependent varaible.

UnivariateOR95% CIP-valueSex, female = ref.0.910.50 - 1.670.77Age, years0.980.96 - 1.000.09Diagnosis1.050.99 – 1.130.08Months between last RTX and vaccination1.061.03 - 1.09<0.001Total number of RTX infusions0.960.92 - 1.010.10Total dose of RTX, mg0.970.92 - 1.020.18Time from first to last RTX treatment1.001.00 - 1.000.57No DMARD treatment0.940.50 - 1.780.85Prednisone, dose in mg0.910.85 - 0.990.02Methotrexate1.710.90 - 3.250.10Hydroxychloroquine0.870.35 - 2.190.77Azathioprine0.230.06 - 0.800.02Multivariate modelMonths between last Rtx and vaccination1.081.04 - 1.11<0.001Prednisone treatment, mg0.910.84 - 0.990.03Azathioprine treatment0.100.02 - 0.440.002

All significant variables in the univariate analysis were included in the multivariate model.

Conclusion

In conclusion, patients with rheumatic diseases treated with RTX have a severely impaired serological response towards the COVID-19 mRNA vaccine. This is especially true if the interval between RTX treatment and vaccination is less than 9 months. For the majority of RTX treated patients, the recommended six months since last RTX is insufficient to develop a humoral response to COVID-19 mRNA vaccines. Our data suggest that the current recommendations of a 6 months interval should be revised.

References

[1]Ammitzbøll C, et al. Impaired antibody response to the BNT162b2 mRNA COVID-19 vaccine in patients with Systemic Lupus Erythematosus and Rheumatoid Arthritis. ACR Open Rheumatol. 2021;

Disclosure of Interests

None declared

POS1198 VACCINATION AGAINST COVID-19 SHOULD BE ENCOURAGED IN PATIENTS WITH RHEUMATIC DISEASE, AS MOST PATIENTS DEVELOP A SEROLOGICAL RESPONSE AGAINST THE VACCINE AND VACCINATION REDUCES SELF-IMPOSED ISOLATION AND SHIELDING BEHAVIOR

Background

Vaccine trials of the SARS-CoV-2 mRNA vaccines were encouraging but excluded most patients with rheumatic diseases (RD) and patients treated with immunosuppressive therapy. However, reports of a more severe COVID-19 disease course in patients with RDs prompted strategies for expediting vaccination of RD patients in most countries.

In addition to the impact experienced by most people of the pandemic, patients with RDs were adversely impacted by the potential risk of severe COVID-19 due to their disease and immunosuppressive treatment. Fear of COVID-19 led to disproportionate anxiety, self-isolation, and shielding behavior for many RD patients at the beginning of the pandemic.

Objectives

We investigated antibody levels in serum against SARS-CoV-2 after a two-dose vaccination with an mRNA vaccine in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). Further, we examined the association between reactogenicity and immunogenicity and how vaccination influenced patient behavior concerning fear of COVID-19 and shielding.

Methods

Patients with SLE or RA from the COPANARD (Corona PANdemic Autoimmune Rheumatic Disease)1 cohort received two doses of an mRNA vaccine between January and August 2021 and had total antibodies against SARS-CoV-2 measured before vaccination and 2 and 9 weeks after the second vaccination. In addition, patients answered an electronic questionnaire before and eight weeks after vaccination concerning behavior, anxiety, and symptoms of depression (PHQ-9).

Results

Three-hundred-and-three patients and 44 blood donors (healthy controls) were included. Significantly fewer patients (90%) had measurable antibodies against SARS-CoV-2 compared to blood donors (100%) after the second vaccination (p<0.001) (Figure 1). Treatment with Rituximab was the strongest predictor of unfavorable vaccine response, as only 27% were seropositive after vaccination. We found a negative effect of prednisone and methotrexate but no effect of age, comorbidity, or pausing medication on seroconversion. Patients experienced significant improvement after vaccination in 10 out of 12 questions regarding behavior and fear of COVID-19, but no change was observed in symptoms of depression (p=0.62) or anxiety (p=0.46).

Figure 1.

Total antibody response against SARS-CoV-2 after two mRNA vaccines. Antibody response against mRNA COVID-19 vaccine pre-vaccination, 1 and 9 weeks after in patients with rheumatic diseases and 5-6 weeks after vaccination in blood donors. (A) Percentage with measurable SARS-CoV-2 antibody results after vaccination. (B) Levels of SARS-CoV-2 antibodies in serum.

Conclusion

The majority of patients with SLE or RA had a measurable serological response to the COVID-19 mRNA vaccine after two doses. Treatment with Rituximab was the strongest predictor of no seroconversion.

Our findings warrant encouragement of vaccination against COVID-19 for patients with RD, as most patients benefits with both a serological immune response and reduced isolation and shielding behavior.

References

[1]Ammitzbøll C, Andersen JB, Vils SR, Mistegaard CE, Mikkelsen S, Erikstrup C, Thomsen MK, Hauge EM, Troldborg A. Arthritis Care Res (Hoboken). 2021 May 31:10.1002/acr.24716. doi: 10.1002/acr.24716. Online ahead of print.

Disclosure of Interests

None declared

Flow cytometry detection of vitamin D receptor changes during vitamin D treatment in Crohn's disease

Crohn's disease (CD) is a chronic inflammatory disease associated with a dysregulated T cell response towards intestinal microflora. Vitamin D has immune modulatory effects on T cells through the nuclear vitamin D receptor (VDR) in vitro. It is unclear how oral vitamin D treatment affects VDR expression. The aim of this study was to establish a flow cytometry protocol, including nuclear and cytoplasmic VDR expression, and to investigate the effects of vitamin D treatment on T cell VDR expression in CD patients. The flow cytometry protocol for VDR staining was developed using the human acute monocytic leukaemia cell line (THP-1). The protocol was evaluated in anti-CD3/CD28-stimulated peripheral blood mononuclear cells (PBMCs) from vitamin D3- (n = 9) and placebo-treated (n = 9) CD patients. Anti-VDR-stained PBMCs were examined by flow cytometry, and their cytokine production was determined by cytokine bead array. VDR, CYP27B1 and RXRα mRNA expression levels in CD4(+) T cells were measured by quantitative reverse transcriptase polymerase chain reaction. The flow cytometry protocol enabled detection of cytoplasmic and nuclear VDR expression. The results were confirmed by confocal microscopy and supported by correlation with VDR mRNA expression. VDR expression in CD4(+) T cells increased following stimulation. This VDR up-regulation was inhibited with 30% by vitamin D treatment compared to placebo in CD patients (P = 0027). VDR expression was correlated with in-vitro interferon-γ production in stimulated PBMCs (P = 0.01). Flow cytometry is a useful method with which to measure intracellular VDR expression. Vitamin D treatment in CD patients reduces T cell receptor-mediated VDR up-regulation.

Vitamin D3 treatment of Crohn's disease patients increases stimulated T cell IL-6 production and proliferation

BACKGROUND

Vitamin D3 has shown immune-modulating effects in CD4+ T cells from Crohn's disease patients in vitro.

AIM

To investigate the effects of in vivo vitamin D3 treatment on T cells in Crohn's disease patients.

METHODS

Peripheral blood mononuclear cells (PBMC) were isolated at week 0 and at week 26 from 10 vitamin D3- and 10 placebo-treated Crohn's disease patients participating in a randomized, placebo-controlled, clinical trial study. Monocyte-depleted PBMC were stimulated with anti-CD3 and anti-CD28, and cultured for 7, days, to investigate CD4+ T-cell proliferation and T-cell cytokine production.

RESULTS

In vitamin D3-treated patients, the median 25-hydroxyvitamin D3 levels increased 70 nmol/L compared with -5 nmol/L in the placebo group. Vitamin D3 treatment increased interleukin-6 production (delta = 188 pg/mL, range: -444 to 4071) compared with a decrease in the placebo group (delta = -896 pg/mL, range: -3841 to 1323) (P < 0.02, Wilcoxon rank sum test). Interestingly, vitamin D3 increased the amount of proliferating stimulated CD4+ T cells from median 41% (range: 10-75%) to 56% (range: 26-77%) (P = 0.02, Wilcoxon rank sum test).

CONCLUSIONS

Vitamin D3 treatment of Crohn's disease patients increased the IL-6 levels. Interestingly, vitamin D3 treatment enhanced the CD4+ T cell proliferation.

Clinical trial: vitamin D3 treatment in Crohn's disease - a randomized double-blind placebo-controlled study

BACKGROUND

Vitamin D has immune-regulatory functions in experimental colitis, and low vitamin D levels are present in Crohn's disease.

AIM

To assess the effectiveness of vitamin D3 treatment in Crohn's disease with regard to improved disease course.

METHODS

We performed a randomized double-blind placebo-controlled trial to assess the benefits of oral vitamin D3 treatment in Crohn's disease. We included 108 patients with Crohn's disease in remission, of which fourteen were excluded later. Patients were randomized to receive either 1200 IU vitamin D3 (n = 46) or placebo (n = 48) once daily during 12 months. The primary endpoint was clinical relapse.

RESULTS

Oral vitamin D3 treatment with 1200 IU daily increased serum 25OHD from mean 69 nmol/L [standard deviation (s.d.) 31 nmol/L] to mean 96 nmol/L (s.d. 27 nmol/L) after 3 months (P < 0.001). The relapse rate was lower among patients treated with vitamin D3 (6/46 or 13%) than among patients treated with placebo (14/48 or 29%), (P = 0.06).

CONCLUSIONS

Oral supplementation with 1200 IE vitamin D3 significantly increased serum vitamin D levels and insignificantly reduced the risk of relapse from 29% to 13%, (P = 0.06). Given that vitamin D3 treatment might be effective in Crohn's disease, we suggest larger studies to elucidate this matter further. ClinicalTrial.gov(NCT00122184).