key: cord-1003583-yxpauc2k
authors: Prentice, Ralley E.; Rentsch, Clarissa; Al‐Ani, Aysha H.; Zhang, Eva; Johnson, Douglas; Halliday, John; Bryant, Robert; Begun, Jacob; Ward, Mark G.; Lewindon, Peter J.; Connor, Susan J.; Ghaly, Simon; Christensen, Britt
title: SARS‐CoV‐2 vaccination in patients with inflammatory bowel disease
date: 2021-07-23
journal: GastroHep
DOI: 10.1002/ygh2.473
sha: b45e00f8818f89e4eb726ac12a812b4105fb57d8
doc_id: 1003583
cord_uid: yxpauc2k

BACKGROUND: The current COVID‐19 pandemic, caused by Severe Acute Respiratory Syndrome‐Coronavirus‐2 (SARS‐CoV‐2), has drastically impacted societies worldwide. Vaccination against SARS‐CoV‐2 is expected to play a key role in the management of this pandemic. Inflammatory conditions such as inflammatory bowel disease (IBD) often require chronic immunosuppression, which can influence vaccination decisions. AIM: This review article aims to describe the most commonly available SARS‐CoV‐2 vaccination vectors globally, assess the potential benefits and concerns of vaccination in the setting of immunosuppression and provide medical practitioners with guidance regarding SARS‐CoV‐2 vaccination in patients with IBD. METHODS: All published Phase 1/2 and/or Phase 3 and 4 studies of SARS‐CoV‐2 vaccinations were reviewed. IBD international society position papers, safety registry data and media releases from pharmaceutical companies as well as administrative and medicines regulatory bodies were included. General vaccine evidence and recommendations in immunosuppressed patients were reviewed for context. Society position papers regarding special populations, including immunosuppressed, pregnant and breast‐feeding individuals were also evaluated. Literature was critically analysed and summarised. RESULTS: Vaccination against SARS‐CoV‐2 is supported in all adult, non‐pregnant individuals with IBD without contraindication. There is the potential that vaccine efficacy may be reduced in those who are immunosuppressed; however, medical therapies should not be withheld in order to undertake vaccination. SARS‐CoV‐2 vaccines are safe, but data specific to immunosuppressed patients remain limited. CONCLUSIONS: SARS‐CoV‐2 vaccination is essential from both an individual patient and community perspective and should be encouraged in patients with IBD. Recommendations must be continually updated as real‐world and trial‐based evidence emerges.

The COVID-19 pandemic is one of the most devastating global events in modern history and one for which the full toll on humanity remains to be seen. At first recognition of SARS-CoV-2 human transmission, the emergent need for a preventative vaccine became apparent. This was the catalyst for the expedient and rigorous manufacturing of a successful vaccine, an astounding feat unparalleled in history. SARS-CoV-2 vaccination provides our global community with hope for stabilisation and eventual recovery, with healthcare workers playing an essential role in safe vaccine delivery. The rapidity of vaccine development, together with the urgent need for their safe deployment, also presents significant challenges, given the paucity of experience. This is particularly the case for groups excluded from vaccine trial populations, such as immunosuppressed individuals, in whom it is prudent to balance the need for protective vaccination against safety concerns.

Inflammatory bowel disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is characterised by dysregulated inflammation in the gastrointestinal tract. The primary goal of IBD management is controlling this inflammation, with a significant number of patients requiring immune-based therapies. 1 These therapies include immunomodulators, tumour necrosis factors (TNF) -antagonists, non-TNF targeted biologics and targeted small molecule therapies. 2 Active IBD and the immunosuppressive therapies integral to its management may weaken the immune system, thereby placing patients with IBD at increased risk of infections. 3 Although current data suggest that IBD alone does not increase the risk of acquisition or severity of symptomatic SARS-CoV-2 infection, thiopurines and baseline corticosteroid use may increase the risk of developing severe COVID-19. [4] [5] [6] Furthermore, SARS-CoV-2 can directly infect gastrointestinal tract cells, via the membrane-bound angiotensin-converting enzyme (ACE) 2 receptor, precipitating colonic inflammation 7 with gastrointestinal symptoms occurring in up to 17.6% of IBD patients with COVID-19. 8 The role of SARS CoV-2 in precipitating and/or aggravating an IBD flare is ill-defined, but it may precipitate or perpetuate disease activity. 9 Effective vaccination is therefore vital, given the potential risk of adverse COVID-19 outcomes in select IBD patients. Non-live vaccinations can be administered in IBD irrespective of medical therapy. 10, 11 Importantly with respect to the SARS-CoV-2 vaccinations, IBD patients on immunosuppression were excluded from clinical trials hence evidence to direct clinical decisions is sparse, but emerging. Practicable guidance to support individuals both delivering and receiving SARS-CoV-2 vaccinations in this population is therefore paramount.

The aim of this review is to summarise the commonly available SARS-CoV-2 vaccination vectors currently available globally, assess the potential benefits and concerns of vaccination in the setting of IBD and immunosuppression, and provide clinicians with advice regarding SARS-CoV-2 vaccination in patients with IBD.

The need for this review was recognised following the international implementation of vaccination programmes. A review utilising EMBASE, MEDLINE and PubMed was conducted. Existing literature and international guidelines pertaining to general vaccinations in the IBD population, including their efficacy and safety, were reviewed for the frame of reference. Evidence regarding the use of the SARS-CoV-2 vaccines, including their efficacy, safety and mechanisms of action, was also reviewed to provide context. This included reference to published position statements from the British Society of Gastroenterology 12 and the International Organisation for the Study of Inflammatory Bowel Disease (IOBD) 13 regarding SARS-CoV-2 recommendations in immunosuppressed patients were reviewed for context. Society position papers regarding special populations, including immunosuppressed, pregnant and breast-feeding individuals were also evaluated. Literature was critically analysed and summarised.

Results: Vaccination against SARS-CoV-2 is supported in all adult, non-pregnant individuals with IBD without contraindication. There is the potential that vaccine efficacy may be reduced in those who are immunosuppressed; however, medical therapies should not be withheld in order to undertake vaccination. SARS-CoV-2 vaccines are safe, but data specific to immunosuppressed patients remain limited.

Conclusions: SARS-CoV-2 vaccination is essential from both an individual patient and community perspective and should be encouraged in patients with IBD.

Recommendations must be continually updated as real-world and trial-based evidence emerges. vaccination in patients with IBD. The focus was on vaccinations likely to become available in the short-to medium-term globally with at least phase 2 data published at the time of writing.

Articles specific to the use of the COVID-19 vaccinations in patients with IBD, pregnant, breastfeeding and immunosuppressed   patients consist mainly of expert opinion, regulatory agency, safety reporting registry data and society position statements, thus are based on low levels of evidence. As such, recommendations must be interpreted with caution and will be subject to reassessment and revision.

Due to the frequent need for immunosuppressive therapies, there has been concern that IBD patients are at increased risk of contracting SARS-CoV-2 and developing COVID-19 complications. Over the last year, the international registry of patients with IBD and COVID-19

(the SECURE-IBD registry) has attempted to determine if this is in fact the case. Reassuringly, existing data have demonstrated that IBD alone does not appear to increase the risk of developing severe SARS-CoV-2 infection. 4 As with the wider population, host-related factors, including increasing age and comorbidities, are the main factors associated with an increased risk of severe COVID-19. 4-6 (Table 1) While biologic monotherapy has not been associated with the development of severe COVID-19, thiopurines and baseline corticosteroid use are both risk factors. [4] [5] [6] The evidence regarding 5-aminosalicylates (5ASAs) and risk of severe COVID-19 is mixed. Danish registry data failed to demonstrate an association, 14 while SECURE-IBD data were suggestive of an increased risk in comparison to those exposed to anti-TNF and other medical therapies, but not in comparison to those receiving no medical therapy and there is no discernible dose-response. 5 Further large cohort data are required, but the risk is postulated to be driven by confounders. 14 

An exhaustive discussion of the SARS-CoV-2 vaccine mechanism is beyond the scope of this review. In brief, available vaccines target various pathways of SARS-CoV-2 infection, aiming to induce an immune response mimicking that induced by exposure to the virus itself. COVID-19 enters the cell via its spike protein (glycoprotein S), which contains a receptor-binding domain (RBD). This domain interacts with ACE-2 receptors on the human cell surface, permitting cellular entry. 15 Humoral immune response to the viral surface glycoproteins is key to achieving immunity. Preventing viral protein and cellular receptor interaction with neutralising antibodies enables viral clearance. 16 The T cell response to SARS-CoV-2 is also critical. Anti-viral cytokines are released by SARS-CoV-2 specific CD4+ T helper 1 (TH1) cells, including interferon (IFN)-gamma and TNF-alpha. Cytotoxic CD8+ T cells additionally directly kill virally infected cells. T helper cells provide stimulation for ongoing B cellmediated antibody response to viral surface antigens. Thus, an effective vaccination must induce both a humoral and T cell response to provide durable immunisation. 16 Successful SARS-CoV-2 vaccination formats have demonstrated both T and B cell response,   as measured via antibody response and IFN-gamma production respectively. 17

The vaccine platforms most commonly being implemented include mRNA, viral vector-based, inactivated vaccines, and recombinant protein formats. 18 Similarly, the Sinovac whole inactivated virus vaccine may increase neutralising antibody titres when the interval at which it is provided is extended from two to four weeks. 36 Consequently, providers and regulatory agencies worldwide must remain cognisant of the fact that evidence regarding both the overall efficacy of and optimal schedule for providing the available SARs-CoV-2

vaccinations is continually evolving. 

As vaccination programmes are instituted internationally, further phase As an extension to this data, the same group evaluated the seroconversion rates to the Pfizer/BioNtech and AstraZeneca vaccines in 865 infliximab-exposed patients, compared to a reference cohort of 428 vedolizumab-treated patients without prior evidence of infection. 54 Antibody responses were assessed at weeks 3 to 10 following vaccination. Older age, immunomodulator use, Crohn's disease (vs UC or IBD unclassified), and current smoking were associated with lower anti-SARS-CoV-2 antibody concentrations irrespective of the vaccine received. As predicted by the original CLARITY IBD data, anti-SARS-CoV-2 antibody levels and rates of seroconversion were lower following primary (first dose) vaccination with both the Pfizer/BioNtech and AstraZeneca vaccines in patients with IBD treated with infliximab compared to vedolizumab. Importantly, however, after two vaccines only 18% of infliximab exposed and 8% of vedolizumab-exposed patients failed to mount an adequate serological response. 54 Thus, ensuring the complete vaccine schedule is completed in a timely fashion is important in biologic-exposed patients.

The 

The In the CLARITY IBD study, 54 Combination therapy with an immunomodulator and anti-TNF also have lower rates of seroprotective response to influenza vaccination compared to non-immunosuppressed patients. [79] [80] [81] This does not vary with the timing of vaccine and anti-TNF schedule, 80 but may be overcome with high dose vaccination.

Booster dosing has not been shown to be effective in enhancing vaccine efficacy. 82, 83 As discussed previously, data from the CLARITY-IBD study suggest those exposed to anti-TNF may have an attenuated serological response to both SARS CoV-2 vaccination and infection. 53, 54 However, protective antibody titre levels can be obtained, and are common following completion of a two-dose vaccine schedule. 58, 65, 84 The same is observed with hepatitis A vaccination, with 86% of anti-TNF treated IBD patients achieving adequate seroprotection with two vaccine doses. 74 

Ustekinumab, an IL12/23p40 subunit antibody, is a well-established therapeutic option in CD, with evidence and experience accumulating in UC. 85 The antibody response to the first dose of SARS-COV-2 vaccination may be lower in IBD patients receiving immunomodulators; however, the overall antibody response is adequate after completing the vaccination schedule. Treatment with immunomodulators should not deter patients from SARS-CoV-2 vaccination.

• Vaccine efficacy may be decreased by anti-TNF therapy, particularly in combination with an immunomodulator, although data are conflicting. • A seroprotective vaccine response is still achieved with the majority of vaccines. • Recent data suggest seroprotection may be reduced with SARS-CoV-2 vaccines following a single dose however patients responded appropriately after their second dose; therefore, prompt administration of the second dose where relevant should be instigated.Anti-TNF therapy commencement should be delayed two weeks post SARS-CoV-2 vaccination to optimise efficacy where safe to do so. • Treatment with anti-TNF should not be interrupted to vaccinate with non-live or non-replicative viral vector vaccines including SARS-CoV-2 vaccines.

Vaccines are efficacious in IBD patients receiving ustekinumab, although data are limited. Treatment with ustekinumab should not be interrupted to vaccinate with non-live or non-replicative viral vector vaccines including SARS-CoV-2 vaccines.

Due to its gut-specific mechanism of action, the effects of vedolizumab on parenteral vaccination response are unlikely to be marked. A recent study in patients receiving vedolizumab was inconclusive with respect to influenza vaccination efficacy on the basis of high baseline influenza antibody titres. 89 Parenteral hepatitis B vaccination response in healthy controls receiving a dose of vedolizumab, compared to those receiving placebo are equivalent. 89, 90 In comparison to anti-TNF therapy,

the CLARITY-IBD study demonstrated more robust antibody responses to SARS-CoV-2 vaccination, but the ICARUS-IBD study identified a lower antibody response to mRNA vaccination in vedolizumab-exposed patients in comparison to healthy controls. 54 

When counselling prior to vaccination, patients must be informed of the relatively common incidence of mild injection site tenderness and systemic flu-like reactions. Fatigue and headache were reported in 59% and 54% respectively of young vaccine recipients following the second dose of the Pfizer-BioNTech vaccine, 25 as opposed to 23% and 24% respectively in the placebo group.

This is comparable to the side effect profile of commonly utilised vaccines. 12 Similarly, injection site tenderness was reported in over 60% of patients receiving the AstraZeneca vaccine. Myalgia, chills, malaise, arthralgia and fever were also common. 99 Given the paucity of safety data regarding the administration of any SARS-CoV-2 vaccine and other vaccines in conjunction, including the influenza vaccine, it is prudent to ensure a 14-day interval is maintained. 101 More recently, concern regarding the risk of vaccine provoked Vaccine efficacy may be decreased with the use of tofacitinib although data are limited. Delaying SARS-CoV-2 vaccination until patients have completed tofacitinib induction and are receiving maintenance doses of 5 mg BD is recommenced where this will not be expected to delay vaccination excessively. Tofacitinib commencement should be delayed two weeks postvaccination to optimise efficacy where safe to do so. Tofacitinib therapy should not be interrupted to vaccinate with nonlive or non-replicative viral vector vaccines including SARS-CoV-2 vaccines occurring within four to 20 days of the first dose in the majority of cases. 102 Although rare, the incidence of this highly morbid and frequently mortal (at the time of writing (18/86)) 102,103 adverse event was seven times the expected rate in a German population, with a plausible connection to vaccination. 104 The majority of cases have occurred in women under the age of 50 with no associated co-morbidities. The

European Medicines Agency (EMA) has formally recognised the association but presently suggests the benefits of vaccination outweigh the risks. However, specific government directives in each country must be considered and are highly variable in accordance with the risk of SARS-CoV-2 acquisition. 105 CI 0.10-0.94; P = 0.049). 110 Whether the reduction in rates of adverse events reflects the reduced serologic response to vaccination observed in existing cohort studies 54,55 is uncertain, but theoretically plausible.

Pregnancy poses an increased risk for severe COVID-19, thus immunisation must be considered particularly in those at high risk of SARS-CoV-2 acquisition or with additional risk factors for severe disease. 12, 111, 112 This includes pregnant, immunosuppressed patients with IBD, particularly those receiving corticosteroids, thiopurines or combination anti-TNF therapy. There is a distinct lack of evidence regarding the safety of existing SARS-CoV-2 vaccines in pregnancy, with pregnant patients excluded from the seminal trials. 25, 100 Currently, it is recommended that SARS-CoV-2 vaccination be offered to pregnant and lactating women with IBD if they would otherwise be offered the vaccine (ie if they did not have IBD). 13 Registry data will inform future practice, including from the v-safe registry. This is established and maintained by the CDC as an electronic reporting tool for outcomes subsequent to SARS-CoV-2 vaccination, has thus far included more than 30,000 self-reported pregnant women. The majority of women were vaccinated in the first trimester and with the Pfizer-BioNTech vaccine. Thus far, there has been no signal for any pregnancy-specific safety concerns, with the observed miscarriage rate comparable to that of the background population. 113 While this is reassuring, specific guidance from regulatory agencies is awaited.

Like in the setting of pregnancy, data specific to the safety of SARS-CoV-2 vaccination in breastfeeding women is extremely limited. 114 The British Royal College of Obstetricians and Gynaecologists recommends that breastfeeding women be offered the SARS-CoV-2 vaccination if they otherwise would be, following informed discussion with respect to the lack of specific safety data. 115 Of interest, a pre-print study of six women who received a COVID-19 mRNA vaccine while lactating, found that following vaccination the breast milk transmissible SARS-CoV-2 immunoglobulins which potentially may be protective for infants. 116

Most of the existing SARS-CoV-2 vaccines are not approved in children younger than 16 years old, due to exclusion from initial trials. Fortunately, paediatric IBD patients appear to be at low risk of severe COVID-19 irrespective of medication exposures. 117 Vaccination trials are ongoing in the paediatric population. The use of the Pfizer vaccine in a cohort of 2260 children aged 12-15 had been demonstrated to be 100% effective with no concerning or unexpected safety signals, and there has been recent emergency use authorisation for this vaccine in this age group. 118 A phase 1/2/3 trial in 6 months to 11-year-olds has recently commenced. 118

The COVID-19 pandemic continues to evolve rapidly, with a need to prioritise the prevention of acquisition and progression to severe disease. These recommendations, based on the available evidence presently, will be modified as data specific to the immunosuppressed IBD population accumulates. Clinicians must focus on providing patients with sound, well-reasoned advice to support their decision to vaccinate. This is especially important in the setting of an immunosuppressive medical condition, where safety and efficacy concerns may be particularly anxiety-provoking.

All patients with IBD should be vaccinated against pneumococcal and influenza in accordance with pre-existing international society guidelines, regardless of IBD medical therapy.

SARS-CoV-2 vaccination is recommended for all adult non-pregnant individuals with IBD without contraindication, regardless of IBD medical therapy.

Individuals on immunosuppressive therapies for IBD including corticosteroids, immunomodulators and anti-TNFs may have reduced vaccine efficacy, in particular, to single-dose vaccination but this should not deter patients or practitioners from vaccinating and should encourage completion of a two-dose vaccination course.

Individuals receiving immunosuppressive medical therapies for IBD must continue to implement non-pharmaceutical practices to minimise the risk of SARS-CoV-2 acquisition due to the theoretical risk of reduced vaccine efficacy.

Data regarding the use of SARS-CoV-2 in pregnant individuals remain limited. Therefore, the relative risks and benefits of vaccination must be discussed with each patient individually.

SARS-CoV-2 vaccination cannot be recommended in individuals with IBD younger than 12 years of age presently, due to lack of efficacy and safety data and the relatively low risk of severe COVID-19 in this population, although data are emerging rapidly.

Individuals with a past history of anaphylaxis to medicines should consult with their medical practitioner prior to receiving a SARS-CoV-2 vaccine. SARS-CoV-2 vaccinations are contraindicated in individuals with a history of anaphylaxis to a SARS-CoV-2 vaccine or their components according to manufacturer recommendations. However, speciality immunologist review should be considered if the risks of COVID-19 in the individual outweigh the risks of medically supervised vaccination.

Women with IBD who are pregnant, or breastfeeding should be offered SARS-CoV-2 if they would otherwise be a candidate for it, with an individualised and collaborative risk-benefit analysis undertaken for each patient.

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