POS0260 LONG-TERM HUMORAL RESPONSE TO SARS-CoV-2 VACCINATION IN PATIENTS WITH IMMUNE-MEDIATED INFLAMMATORY DISEASE

Background

The first vaccine against SARS-CoV-2 was approved in December 2020. Immunogenicity of SARS-CoV2 vaccines in patients with immune-mediated inflammatory disease (IMID) have so far been evaluated in the 2-6 weeks following complete vaccination and risk groups for poor early vaccine response have been identified leading to specific vaccination recommendations. However, data on the long-term course and persistence of vaccine response in IMID patients, as well as the outcomes of the specific recommendations are lacking.

Objectives

To evaluate the long-term course of humoral response to SARS-CoV-2 vaccination in a large prospective cohort of IMID patients and non-IMID controls with a follow-up duration of up-to to 10 months after the first vaccine dose.

Methods

We have initiated a prospective dynamic cohort of IMID patients and healthy controls in February 2020 to monitor immune response to SARS-CoV-2 and respiratory infections including COVID-19 (1). Participants who contributed data starting from the 4 weeks before their first vaccination onwards were included in this analysis. Antibodies against SARS-CoV-2 spike protein were quantified with an ELISA from Euroimmun (Lübeck, Germany) with an optical density cutoff of 0.8. We fitted linear mixed-effect models for log-transformed antibody levels using time splines with adjustment for age and sex. Marginal mean antibody levels with 95% confidence intervals (CI) were estimated at selected time points for IMID patients and controls with double vaccination. We descriptively analyzed the observed antibody levels over time in cohort participants receiving two vaccinations vs. three vaccinations.

Results

Among 5076 cohort participants, 3147 IMID patients and healthy controls (mean (SD) age 49 (16)) provided 4756 samples for this analysis between December 2020 and 2021, with a median (IQR) 28 (14-31) weeks of follow-up after the first vaccination (Table 1). 2965 (94%) participants had received at least 2 and 223 (7%) participants had received three vaccine doses by the date of their latest sampling. In IMID patients, age and sex-adjusted estimated marginal mean antibody levels waned after week 16 and were substantially reduced at all time points compared to the controls, finally dropping to the borderline range (1.01, 95%CI 0.86 to 1.19) at week 40 (Figure 1A, Table 1). A third dose was given to 128 (7%) of IMID patients with a poor response to 2 vaccine doses after a median 20 weeks of the second dose (IQR 10 to 26 weeks). After the third dose, antibody levels in IMID patients were comparable to those of healthy controls at 40 weeks who had three vaccine doses. These were also higher than that of IMID patients and controls who did not receive a third dose (Figure 1B).

Table 1.

Participant characteristics and antibody levels

Healthy controlsIMID N11991948 Age, mean (SD)40.8 (13.5)54.3 (14.8) Follow-up, weeks, median (IQR)31.1 (23.8-36.6)19.6 (12.3-26.6) Follow-up range, weeks,1.6-46.11.7-46.3Sex, n(%) Female554 (46.2)1136 (58.3)Vaccine intervals, ´median (IQR) 1st to 2nd dose4.6 (3.0-6.0)6.0 (5.0-6.1) 2nd to 3rd dose29.6 (26.9-36.4)19.9 (10.0-26.1)Diagnosis, n (%) Spondyloarthritis-713 (36.6) Rheumatoid arthritis-489 (25.1) Autoimmune disease, systemic+-420 (21.5) Inflammatory bowel disease-219 (11.2) Psoriasis-107 (5.5)Mean* antibody levels after 1st dose Week-84.16 (3.89 to 4.45)2.97 (2.83 to 3.12) Week-168.39 (7.81 to 9.02)5.04 (4.81 to 5.28) Week-325.02 (4.73 to 5.33)2.52 (2.32 to 2.74) Week-402.14 (1.95 to 2.35)1.01 (0.86 to 1.19)

+ Systemic lupus, systemic sclerosis, Sjögren’s syndrome, vasculitis

* Estimated marginal means adjusted for age and sex.

Figure 1.

Conclusion

Humoral response to vaccination against SARS-CoV-2 was weaker in IMID patients compared to controls at all time points after the first vaccine dose and practically disappeared after 1 year. IMID patients can still achieve a good antibody response with a third dose even after a weak response with two doses.

References

[1]Simon D et al Nat Commun 2020

Disclosure of Interests

None declared

Impact of cytokine inhibitor therapy on the prevalence, seroconversion rate and longevity of the humoral immune response against SARS-CoV-2 in an unvaccinated cohort

OBJECTIVE

To investigate the impact of biological DMARD treatment on the prevalence, seroconversion rate and longevity of the humoral immune response against SARS-CoV-2 in IMID patients.

METHODS

Anti-SARS-CoV-2 IgG antibodies were measured in a prospective cohort of healthcare and non-healthcare controls and IMID patients receiving no treatment or treated with conventional or biological DMARDs during the first and second COVID-19 waves. Regression models adjusting for age, sex, sampling-time and exposure risk behavior were used for calculating relative risks of seropositivity. Seroconversion rates were assessed in participants with PCR-proven SARS-CoV-2 infection. Antibody response longevity was evaluated by re-assessing participants who tested positive during the first wave.

RESULTS

4508 participants (2869 IMID patients, 1639 total controls) were analyzed. Unadjusted (RR 0.44; 95% CI: 0.31-0.62) and adjusted (RR 0.50; 95% CI: 0.34-0.73) relative risks for SARS-CoV2 IgG were significantly (p<0.001) lower in IMID patients treated with bDMARDs compared to non-healthcare controls, primarily driven by TNF-alpha, IL-17 and IL-23 inhibitors-treated patients. Adjusted relative risks of untreated IMID patients (1.12; 0.75-1.67) or IMID patients receiving csDMARDs (0.70; 0.45-1.08) were not significantly different from non-healthcare controls. Lack of seroconversion in PCR+ participants was more common (38.7%) among bDMARD-treated patients than in non-healthcare controls (16%). Overall 44% of positive participants lost SARS-CoV2 antibodies at follow-up, with higher rates in IMID patients treated with bDMARDs (RR:2.86; 95%CI: 1.43-5.74).

CONCLUSIONS

IMID patients treated with bDMARDs have a lower prevalence of SARS-CoV-2 antibodies, seroconvert less frequently after SARS-CoV-2 infection and may exhibit a reduced longevity of their humoral immune response. This article is protected by copyright. All rights reserved.

Patients with immune-mediated inflammatory diseases receiving cytokine inhibitors have low prevalence of SARS-CoV-2 seroconversion

Immune-mediated inflammatory diseases (IMIDs) of the joints, gut and skin are treated with inhibitors of inflammatory cytokines. These cytokines are involved in the pathogenesis of coronavirus disease 2019 (COVID-19). Investigating anti-SARS-CoV-2 antibody responses in IMIDs we observe a reduced incidence of SARS-CoV-2 seroconversion in IMID patients treated with cytokine inhibitors compared to patients receiving no such inhibitors and two healthy control populations, despite similar social exposure. Hence, cytokine inhibitors seem to at least partially protect from SARS-CoV-2 infection.

Weak Agonistic LPS Restores Intestinal Immune Homeostasis

Generated by gram-negative bacteria, lipopolysaccharides (LPSs) are one of the most abundant and potent immunomodulatory substances present in the intestinal lumen. Interaction of agonistic LPS with the host myeloid-differentiation-2/Toll-like receptor 4 (MD-2/TLR4) receptor complex results in nuclear factor κB (NF-κB) activation, followed by the robust induction of pro-inflammatory immune responses. Here we have isolated LPS from a common gut commensal, Bacteroides vulgatus mpk (BVMPK), which provides only weak agonistic activity. This weak agonistic activity leads to the amelioration of inflammatory immune responses in a mouse model for experimental colitis, and it was in sharp contrast to strong agonists and antagonists. In this context, the administration of BVMPK LPS into mice with severe intestinal inflammation re-established intestinal immune homeostasis within only 2 weeks, resulting in the clearance of all symptoms of inflammation. These inflammation-reducing properties of weak agonistic LPS are grounded in the induction of a special type of endotoxin tolerance via the MD-2/TLR4 receptor complex axis in intestinal lamina propria CD11c⁺ cells. Thus, weak agonistic LPS represents a promising agent to treat diseases involving pathological overactivation of the intestinal immune system, e.g., in inflammatory bowel diseases.