Excipient allergy and importance of complete allergy histories

Kan

Chinmoy

et al. 2023

Preprint

Background: Longitudinal whole-population studies can explore new dimensions in drug allergy research. Excipient allergy testing remains a barrier to allergy evaluation in countries without legislations mandating ingredient disclosure in registered drugs. The Comprehensive Excipient and Drug Allergy Registry (CEDAR) was established to investigate Hong Kong’s drug allergy landscape and potential role of excipient registries. Methods: Drug allergy data from over 7,337,778 individuals between 2016-2021 was analyzed. Excipient lists were gathered from all formulations of the top 50 reported drug allergies and checked for the presence of polyethylene glycol (PEG). Results: The absolute-prevalence and -incidence of reported drug allergy was 5.61% and 277/100,000 population in 2021, respectively. Annual incidence of newly reported drug allergy was stable between 2016-2019, until a significant drop in 2020 (-16.3%, p=0.037). The most common implicated drugs were anti-infectives (245,832 [44.5%]), NSAIDs (106,843 [19.3%]), and nervous system drugs (45,802 [8.3%]). There was significant higher incidence among individuals aged >40, contributing to the majority of newly reported allergies (377,004, 68.2%). Beta-lactams and nervous system drugs were the most common reported culprits of anaphylaxis and Stevens-Johnson syndrome. CEDAR was unable to confirm presence or absence of PEG in any of the top reported culprits due to insufficient excipient information. Conclusion: We report the detailed drug allergy landscape of the Hong Kong population. Excipient registries are ineffective in countries without mandatory excipient listings . Contrary to traditional doagma, we identified a disproportionately higher incident drug allergy among middle-aged and older patients. Findings need to be confirmed by region-specific big data studies.

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Disproportionate drug allergy labelling among middle-aged patients and barriers to excipient allergy testing from the Hong Kong Comprehensive Excipient and Drug Allergy Registry (CEDAR)

Kan

Chinmoy

et al. 2023

Preprint

“…While a history of severe, immediate-type allergy to multiple classes of drugs is unlikely to be associated with COVID-19 vaccine allergy, we recommend these patients to receive a non-PEG containing vaccine instead. This is due to Hong Kong’s problematic drug legislation, which does not require full disclosure of excipients in listed drugs, making it extremely difficult to diagnose excipient allergies [ 16 ]. In our local study, although only 2% of prevaccination patients were recommended to defer vaccinations, over 80% of these patients had multiple, suspicious drug allergy histories which could point towards potentially undiagnosed excipient allergies.…”

Section: Discussionmentioning

confidence: 99%

Updated consensus statements on COVID-19 Vaccine Allergy Safety in Hong Kong

Leung

et al. 2022

Asia Pacific Allergy

Self Cite

Due to global concerns over coronavirus disease 2019 (COVID-19) vaccine-associated allergic reactions; the Hong Kong Institute of Allergy (HKIA) formulated an initial set of consensus statements (CS) on COVID-19 Vaccine Allergy Safety (VAS) in early 2021. Following accumulation of both local and international experience on and COVID-19 VAS, the HKIA task force reformed to update the Hong Kong consensus on COVID-19 VAS. A nominated task force of experts managing patients with drug and vaccine allergies in Hong Kong formulated the updated CS by unanimous decision. A total of 9 new statements were established. Individuals with history of food allergies and anaphylaxis unrelated to the components of COVID-19 vaccines do not require allergist review prior to vaccination. Individuals with history suspicious of an excipient allergy may now be vaccinated with a non-PEG containing vaccine without prior allergist assessment. Individuals with suspected mild allergic reactions following prior COVID-19 vaccination can proceed with the next dose. Only individuals who present with immediate-type allergic reaction with systemic symptoms or more severe nonimmediate type reactions should defer their next dose until allergist review. The remaining statements regarding adequate safety during vaccination and advocation for legislative changes regarding excipient disclosure in Hong Kong remained unchanged from the prior CS. The updated CS are updated in accordance with local and international experience thus far and serve as guidance for local frontline healthcare providers to further promote safe COVID-19 vaccine uptake in Hong Kong.

“…[22][23][24] However, this sole exclusion criterion remains impractical in Hong Kong due to deficiencies in our pharmaceutical legislation. 25 Registered drugs in Hong Kong are still not mandated to include excipient lists in product inserts. In the absence of this information, excipient allergies remain almost impossible to diagnose.…”

Section: Discussionmentioning

confidence: 99%

Experience of the first 1127 COVID-19 Vaccine Allergy Safety patients in Hong Kong – Clinical outcomes, barriers to vaccination, and urgency for reform

World Allergy Organization Journal

Mok

Chan

et al. 2022

Self Cite

Introduction Hong Kong has had a low incidence of COVID-19 vaccine related anaphylaxis, partly due to its Vaccine Allergy Safety (VAS) guidelines for screening those at higher risk of COVID-19 vaccine-associated allergic reactions. We characterize the initial experience of the VAS clinics, as well as the impact of unnecessary referrals to the vaccination program. Methods All patients attending the VAS Clinics of the public and private health services between February and June, 2021 were reviewed. Results Out of 1127 patients assessed at VAS clinics, 1102 (97.8%) patients were recommended for vaccination. Out of those contacted, more than 80% (450/558) received vaccination successfully; the remaining had not yet booked their vaccinations. The majority (87.5%) of patients not recommended was due to potential excipient allergies. Males were significantly more likely to be recommended (OR= 5.822, 95% CI=1.361-24.903, p= 0.007), but no other features were associated with recommendation for vaccination. Almost half (45.1%) of public service referrals were rejected due to insufficient information or incorrect indications for referral. The majority of cases (56.2%) of patients referred for suspected “anaphylaxis” did not fulfil diagnostic criteria. Discussion COVID-19 vaccination is very safe and 98% of high-risk patients were recommended for vaccination. Barriers to VAS include a high proportion of inappropriate referrals, inaccurate diagnoses of anaphylaxis and inability to diagnose excipient allergies. Our data validates that a prior history of COVID-vaccine unrelated anaphylaxis should be removed as a precaution for vaccination. Closer collaborations between primary care and allergy specialists and changes in pharmaceutical legislation should be made a priority to promote vaccination uptake.