Humoral response to coronavirus disease-19 vaccines is dependent on dosage and timing of rituximab in patients with rheumatoid arthritis

Effectiveness and Safety of the COVID-19 Vaccine in Patients with Rheumatoid Arthritis in a Real-World Setting

Novel mechanisms of COVID-19 vaccines raised concern about their potential immunogenicity in patients with rheumatoid arthritis (RA) undergoing immunomodulatory treatments. We designed a retrospective single-center study to investigate their effectiveness and safety in this population, analyzing data from the first vaccination program (December 2020-October 2021). Inclusion criteria were availability of post-vaccination serology and a minimum subsequent follow-up of 6 months. Binding antibody units (BAU/mL) ≥ 7.1 defined an adequate serological response. Post-vaccine COVID-19 incidence and its timing since vaccination, adverse events (AEs), and RA flares were recorded. Adjusted logistic and linear multivariate regression analyses were carried out to identify factors associated with vaccine response. We included 118 patients (87.2% women, age 65.4 ± 11.6 years, evolution 12.0 ± 9.6 years), of whom 95.8% had a complete vaccination schedule. Adequate humoral immunogenicity was achieved in 88.1% of patients and was associated with previous COVID-19 and mRNA vaccines, whereas smoking, aCCP, age, and DMARDs exerted a negative impact. Post-vaccine COVID-19 occurred in 18.6% of patients, a median of 6.5 months after vaccination. Vaccine AE (19.5%) and RA flares (1.7%) were mostly mild and inversely associated with age. Our results suggest that COVID-19 vaccines induce adequate humoral immunogenicity, with an acceptable safety profile in RA patients.

Infection incidence, timing and dose dependency in rheumatoid arthritis patients treated with rituximab: a retrospective cohort study

OBJECTIVES

Rituximab (RTX) is a safe and effective treatment for RA. However, there are some concerns about infection risk and preliminary data suggest dose and time dependency. This study aims to determine the infection incidence in a large real-life population of RA patients using RTX, with special focus on (ultra-)low dosing and time since last infusion.

METHODS

RA patients treated with 1000, 500 or 200 mg RTX per cycle between 2012 and 2021 at the Sint Maartenskliniek were included in a retrospective cohort study. Patient-, disease-, treatment- and infection characteristics were retrieved from electronic health records. Infection incidence rates, dose and time relations with RTX infusion were analysed using mixed-effects Poisson regression.

RESULTS

Among 490 patients, we identified 819 infections in 1254 patient years. Most infections were mild and respiratory tract infections were most common. Infection incidence rates were 41, 54 and 71 per 100 patient years for doses of 200, 500 and 1000 mg. Incidence rate ratio (IRR) was significantly lower for 200 mg compared with 1000 mg (adjusted IRR 0.35, 95% CI 0.17, 0.72, P = 0.004). In patients receiving 1000 or 500 mg RTX, infections seemed to occur more frequently within the first two months after infusion compared with later on in the treatment cycle, suggesting an association with peak concentration.

CONCLUSION

Ultra-low dosing (200 mg) of RTX is associated with a lower risk of infections in RA. Future interventions focusing on ultra-low dosing and slow release of RTX (e.g. by subcutaneous administration) may lower infection risk.

Long-term clinical and radiological effectiveness and safety of ultralow doses of rituximab in rheumatoid arthritis: observational extension of the REDO trial

BACKGROUND

The REDO trial (REtreatment with Rituximab in RhEmatoid arthritis: Disease Outcome after Dose Optimisation) showed similar disease activity for retreatment with ultralow doses (200 mg and 500 mg per 6 months) compared with standard low-dose rituximab (RTX, 1000 mg per 6 months). We performed an observational extension study of the REDO trial to assess long-term effectiveness.

METHODS

Patients from the REDO trial were followed from start of the trial to censoring in April 2021. RTX use was at the discretion of patient and rheumatologist using treat to target. The primary outcome was disease activity (disease activity score in 28 joints C-reactive protein (DAS28-CRP)), analysed using a longitudinal mixed model by original randomisation and time-varying RTX dose. The original DAS28-CRP non-inferiority (NI) margin of 0.6 was used. RTX dose and persistence, safety and radiological outcomes were also assessed.

FINDINGS

Data from 126 of 142 REDO patients was collected from 15 December 2016, up to 30 April 2021. Drop-outs continued treatment elsewhere (n=3) or did not consent (n=13).Disease activity did not differ by original randomisation group: 1000 mg mean DAS28-CRP (95% CI) of 2.2 (2.0 to 2.5), 500 mg 2.3 (2.1 to 2.4) and 200 mg 2.4 (2.2 to 2.5). Lower time-varying RTX dose was associated with higher DAS28-CRP (0.22 (95% CI 0.05 to 0.40) higher for 200 mg/6 months compared with 1000 mg/6 months), but remained within the NI-margin. RTX persistence was 93%. Median RTX dose was 978 mg (IQR 684-1413) per year, and no association was found between RTX dose and adverse events or radiological damage.

INTERPRETATION

Long-term use of ultralow doses of RTX is effective in patients with rheumatoid arthritis responding to standard dose RTX.

Outcomes of COVID-19 Omicron variant in patients with rheumatoid arthritis: a nationwide Greek cohort study

OBJECTIVES

Patients with RA were at increased risk for COVID-19-associated hospitalization and death during the first year of the pandemic in Greece. We aimed to examine their outcomes after the SARS-Cov-2 Omicron, a more contagious but with milder clinical impacts variant, prevailed.

METHODS

A retrospective, nationwide study was conducted between 1 January 2022 and 30 June 2022 in all RA patients under treatment and matched (1:5) on age, sex and region of domicile random general population comparators. Confirmed SARS-CoV-2 infections, hospitalizations and deaths, anti-rheumatic medications, prior COVID-19, vaccinations and anti-viral medications were recorded.

RESULTS

Among 34 182 RA patients, infections (n = 5569, 16.29%), hospitalizations (n = 489, 1.43%) and deaths (n = 106, 0.31%) were more frequent than among comparators. Incidence rates per 1000 person/years of infection [IRR (95% CI):1.19 (1.16, 1.23)], hospitalization [IRR (95% CI):2.0 (1.82, 2.24)], and death [IRR (95% CI):1.81 (1.44, 2.27)] were increased in RA despite better vaccination coverage (89% vs 84%) and more frequent use of anti-viral medications (2.37% vs 1.08). Logistic regression analysis after correcting for age, sex, vaccinations, prior COVID-19, and anti-viral medications in SARS-CoV-2 infected RA patients and comparators revealed increased risk of hospitalization (OR: 2.02, 95% CI: 1.79, 2.27) and death [OR: 1.73, (95% CI: 1.36, 2.20)] in RA. Among infected RA patients, rituximab treatment conferred increased risks for hospitalization [OR: 6.12, (95% CI: 2.89, 12.92)] and death [OR: 12.06 (95% CI: 3.90, 37.31)], while JAK inhibitors increased only hospitalization risk [OR: 2.18 (95% CI: 1.56, 3.06)].

CONCLUSION

RA remains a risk factor for hospitalization and death in an era of a relatively low COVID-19 fatality rate, pointing to the need of perseverance in vaccination programs and wider use of anti-viral medications.

Safety and efficacy of SARS-CoV-2 vaccination in patients with immune thrombocytopenia: A two-centre review

Multiple studies have reported immune thrombocytopenia (ITP) relapse following SARS-CoV-2 vaccination, however baseline ITP relapse rate and antibody response to vaccination are not known. Patients with ITP who received at least one of the first three SARS-CoV-2 vaccination doses were included in the study. One hundred and twenty-four patients met the inclusion criteria. Relapse rate was 4.2% following a first vaccine dose, 9.1% after a second and 2.9% after a third; baseline relapse rate was 7.6%. Ninety-four per cent of patients who received three vaccine doses developed a clinical antibody response. SARS-CoV-2 vaccination appears to be safe and effective in patients with ITP.

1-year results of treatment with rituximab in polymyalgia rheumatica: an extension study of a randomised double-blind placebo-controlled trial

BACKGROUND

Rituximab was effective for patients with polymyalgia rheumatica in the 21-week BRIDGE-PMR randomised controlled trial. Here, we aimed to assess rates of glucocorticoid-free remission up to 1 year after infusion in an extension of this trial.

METHODS

BRIDGE-PMR was a randomised controlled proof-of-concept trial that enrolled participants with polymyalgia rheumatica according to 2012 European League Against Rheumatism-American College of Rheumatology classification criteria at the Sint Maartenskliniek, Nijmegen, Netherlands. Patients were randomly allocated in a 1:1 ratio to receive one intravenous dose of 1000 mg rituximab or placebo, with identical pre-medication and accelerated glucocorticoid tapering over 17 weeks. After the 21-week study, patients were followed in a double-blind extension until 1 year after infusion during which standard-of-care treatment was provided. The primary outcome after 52 weeks was between-group difference in glucocorticoid-free remission (ie, polymyalgia rheumatica activity score [PMR-AS] <10), assessed in all randomly allocated participants, with data imputed using a predictive mean matching model (provided data were missing at random). A sensitivity analysis restricted to patients with complete data (complete case analysis) was also done. This trial is registered with EudraCT (2018-002641-11) and the Dutch trial database (NL7414).

FINDINGS

Between Dec 18, 2019 and June 8, 2021, 47 patients enrolled in the BRIDGE-PMR were followed up in this extension study (23 [11 women and 12 men] allocated rituximab and 24 [13 women and 11 men] allocated placebo), of who 38 had recently diagnosed polymyalgia rheumatica and nine had relapsing polymyalgia rheumatica. Mean (SD) age was 64 (10) years in the rituximab group and 66 (9) years in the placebo group. All participants were White. Missing data were imputed for six participants (four rituximab, two placebo); because the data were probably missing at random, a complete case analysis was added as sensitivity analyses. In the imputed analysis, the between-group absolute difference reached statistical significance (12 [52%] of 23 in the rituximab group in glucocorticoid-free remission vs five [21%] of 24 participants in the placebo group; absolute difference 31% [95% CI 5 to 57], RR 2·5 [1·0 to 6·0]; p=0·04). In the complete case analysis, nine (47%) of 19 patients in the rituximab group were in glucocorticoid-free remission 1 year after infusion compared with five (23%) of 22 in the placebo group (absolute difference 25% [95% CI -4 to 53], relative risk (RR) 2·1 [95% CI 0·8 to 5·2]; p=0·12). Eight (33%) patients in the placebo group and six (26%) in the rituximab group had adverse events.

INTERPRETATION

After a single dose of rituximab (1000 mg), the proportion of patients with polymyalgia rheumatica in glucocorticoid-free remission remained stable at 1 year after infusion, and a glucocorticoid sparing effect was evident. A larger trial including possibility for retreatment is warranted to confirm these results.

FUNDING

Sint Maartenskliniek.

Optimal time for COVID-19 vaccination in rituximab-treated dermatologic patients

Background

By depleting circulating B lymphocytes, rituximab time-dependently suppresses coronavirus disease 2019 (COVID-19) vaccines’ humoral immunogenicity for a prolonged period. The optimal time to vaccinate rituximab-exposed immune-mediated dermatologic disease (IMDD) patients is currently unclear.

Objective

To estimate the vaccination timeframe that equalized the occurrence of humoral immunogenicity outcomes between rituximab-exposed and rituximab-naïve IMDD patients.

Methods

This retrospective cohort study recruited rituximab-exposed and age-matched rituximab-naïve subjects tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific immunity post-vaccination. Baseline clinical and immunological data (i.e., immunoglobulin levels, lymphocyte immunophenotyping) and SARS-CoV-2-specific immunity levels were extracted. The outcomes compared were the percentages of subjects who produced neutralizing antibodies (seroconversion rates, SR) and SARS-CoV-2-specific IgG levels among seroconverters. The outcomes were first analyzed using multiple regressions adjusted for the effects of corticosteroid use, steroid-spearing agents, and pre-vaccination immunological status (i.e., IgM levels, the percentages of the total, naïve, and memory B lymphocytes) to identify rituximab-related immunogenicity outcomes. The rituximab-related outcome differences with a 95% confidence interval (CI) between groups were calculated, starting by including every subject and then narrowing down to those with longer rituximab-to-vaccination intervals (≥3, ≥6, ≥9, ≥12 months). The desirable cut-off performances were &lt;25% outcome inferiority observed among rituximab-exposed subgroups compared to rituximab-naïve subjects, and the positive likelihood ratio (LR+) for the corresponding outcomes ≥2.

Findings

Forty-five rituximab-exposed and 90 rituximab-naive subjects were included. The regression analysis demonstrated a negative association between rituximab exposure status and SR but not with SARS-CoV-2-specific IgG levels. Nine-month rituximab-to-vaccination cut-off fulfilled our prespecified diagnostic performance (SR difference between rituximab-exposed and rituximab-naïve group [95%CI]: -2.6 [-23.3, 18.1], LR+: 2.6) and coincided with the repopulation of naïve B lymphocytes in these patients.

Conclusions

Nine months of rituximab-to-vaccination interval maximize the immunological benefits of COVID-19 vaccines while avoiding unnecessary delay in vaccination and rituximab treatment for IMDD patients.

Antibody acquisition after second and third SARS-CoV-2 vaccinations in Japanese kidney transplant patients: a prospective study

BACKGROUND

Kidney transplant patients have lower antibody acquisition after SARS-CoV-2 vaccination. The efficacy of vaccines in Japanese kidney transplant patients with specific characteristics, such as predominant living-donor, ABO-incompatible kidney transplant, and low-dose immunosuppression, requires verification.

METHODS

We conducted a prospective study to estimate anti-SARS-CoV-2 antibody levels in 105 kidney transplant patients and 57 controls. Blood samples were obtained before vaccination, 1, 3, and 6 months after second vaccination, and 1 month after third vaccination. We investigated antibody acquisition rates, antibody levels, and factors associated with antibody acquisition.

RESULTS

One month after second vaccination, antibody acquisition was 100% in the controls but only 36.7% in the kidney transplant group (P < 0.001). Antibody levels in positive kidney transplant patients were also lower than in the controls (median, 4.9 arbitrary units vs 106.4 arbitrary units, respectively, P < 0.001). Years after kidney transplant (odds ratio 1.107, 95% confidence interval 1.012-1.211), ABO-incompatible kidney transplant (odds ratio 0.316, 95% confidence interval 0.101-0.991) and mycophenolate mofetil use (odds ratio 0.177, 95% confidence interval 0.054-0.570) were significant predictors for antibody acquisition after second vaccination. After third vaccination, antibody positivity in the kidney transplant group increased to 75.3%, and antibody levels in positive patients were 71.7 arbitrary units. No factors were associated with de novo antibody acquisition.

CONCLUSIONS

In Japanese kidney transplant patients, years after kidney transplant, ABO-incompatible kidney transplant and mycophenolate mofetil use were predictors for antibody acquisition after second vaccination. Third vaccination improves antibody status even in patients who were seronegative after the second vaccination.

Safety and immunogenicity of COVID-19 vaccination in immunocompromised patients

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic poses a great threat to public health. Individuals who are immunocompromised because of the progression of the primary disease or receiving immunosuppressive medications are prone to severe COVID-19 complications and poor outcomes. Abundant data have shown that many COVID-19 vaccines are safe and effective in large-scale populations; however, these clinical trials have excluded immunocompromised populations. Available evidence indicates that immunocompromised populations have a blunted immune response to other vaccines, raising concerns regarding the efficacy of COVID-19 vaccination in these populations. Thus, there is an urgent need to delineate the efficacy of COVID-19 vaccines in these vulnerable populations. Here, we review the characteristics of specific humoral and cellular responses to COVID-19 vaccination in immunocompromised populations, including HIV-infected patients and those receiving immunosuppressive treatment, especially solid organ transplant recipients and those undergoing anti-CD20 treatment. We also addressed the challenges that immunocompromised populations will face in the future pandemic and the need for basic and clinical translational studies to highlight the best vaccination strategies for these populations.

Seroconversion after a third COVID-19 vaccine is affected by rituximab dose but persistence is not in patients with rheumatoid arthritis

Objectives

In patients with rheumatoid arthritis (RA) treated with (ultra-)low dose rituximab (RTX), we investigated (1) the association of dosing and timing of rituximab (RTX) on seroconversion after third COVID-19 vaccination, and (2) persistence of humoral response after two-dose vaccination.

Methods

In this monocentre observational study, patients from the COVAC-cohort were included in the third vaccine analysis if humoral response was obtained 2-6 weeks after third vaccination in previous non-responders, and in the persistence analysis if a follow-up humoral response was obtained before third vaccination in previous responders. Dichotomization between ‘positive’ and ‘negative’ response was based on the assay cut-off. The association between latest RTX dose before first vaccination, timing between latest rituximab and vaccination, and response was analysed with univariable logistic regression.

Results

Of the 196 patients in the cohort, 98 were included in the third vaccine analysis and 23 in the persistence analysis. Third vaccination response was 19/98 (19%) and higher for 200 mg RTX users (5/13, 38%) than 500 and 1000 mg (7/37, 19% and 7/48, 15%). Non-significant trends were seen for higher response with lower dosing (200 versus 1000 mg: OR 3.66, 95% CI 0.93-14.0) and later timing (per month since infusion: OR 1.16, 0.97-1.35). Humoral response persisted in 96% (22/23) and in 89% (8/9) of patients who received RTX between the two measurements.

Conclusion

Repeated vaccination as late as possible after the lowest RTX dose possible seems the best vaccination strategy. A once positive humoral response after COVID-19 vaccination persists irrespective of intercurrent rituximab infusion.

Trial registration

Netherlands Trial Register, https://www.trialregister.nl/, NL9342