Can vaccines interact with drug metabolism?

[Vaccination Against COVID-19 in Patients Treated with Psychotropic Drugs]

Vaccines against SARS-CoV-2 have been available in the European Union since December 2020. Persons suffering from mental illness have an increased risk of a severe or fatal course following an infection with SARS-CoV-2. Thus, the question arises to what extent interactions between the newly approved vaccines and psychotropic drugs may be expected. Data on the tolerability and efficacy of vaccines against SARS-CoV-2 under treatment with psychotropic drugs are not available to date - however, potential interactions can be derived from previous investigations on vaccines against other pathogens, such as a reduced immune response with lower clinical efficacy and an increase in drug plasma levels due to the indirect vaccine-mediated inhibition of metabolizing enzymes. On the other hand, depressed patients treated with antidepressant medication show a better immune response.

Influenza immunization does not predominantly alter levels of phenytoin, and cytochrome P-450 enzymes in epileptic patients receiving phenytoin monotherapy

OBJECTIVE

The study aims to test the effect of influenza vaccination on phenytoin, CYP2C9, and IFNγ levels in epileptic patients receiving phenytoin monotherapy METHODS: Thirty-one epileptic patients receiving stable-dose phenytoin monotherapy were enrolled onto the study. Serum concentrations of phenytoin, CYP2C9, and IFNγ were compared before and after influenza immunization. The participants were given 0.5 mL of quadrivalent influenza vaccine types A and B subvirion. Blood samples were drawn at baseline, and days 3, 7, 14 post-immunization. The outcomes were levels of phenytoin, CYP2C9, IFNγ, and the incidence of adverse events.

RESULTS

No significant changes in serum phenytoin, IFNγ, and CYP2C9 levels between baseline and days 3, 7, and 14 after immunization were found. The mean levels of phenytoin, IFNγ, and CYP2C9, respectively, were 11.94 ± 7.43, 1.14 ± 0.98, and 47.69 ± 37.53 pg/mL (baseline); 12.15 ± 6.57, 2.13 ± 3.41, and 49.44 ± 39.83 pg/mL (day 3); 12.19 ± 7.69, 1.15 ± 0.94, and 49.48 ± 33.83 pg/mL (day 7); 12.79 ± 7.94, 2.15 ± 3.11, and 53.65 ± 40.91 pg/mL (day 14). The incidence of vaccine-related adverse events, which were generally mild and resolved without clinical consequences, was 58.1 %. No seizure or changes in seizure frequency were observed during the study. One patient experienced dizziness and ataxia which were symptoms attributed to phenytoin toxicity (34.57 μg/mL) by day 14.

CONCLUSIONS

Influenza vaccine has no significant effect on the serum phenytoin and CYP2C9 levels in epileptic patients receiving chronic phenytoin monotherapy. The administration of influenza vaccine to epileptic patients receiving phenytoin monotherapy appears to be safe. Therefore, it is not necessary to routinely measure the serum phenytoin level after influenza immunization.

Personalized Cancer Vaccines: Clinical Landscape, Challenges, and Opportunities

Tremendous innovation is underway among a rapidly expanding repertoire of promising personalized immune-based treatments. Therapeutic cancer vaccines (TCVs) are attractive systemic immunotherapies that activate and expand antigen-specific CD8⁺ and CD4⁺ T cells to enhance anti-tumor immunity. Our review highlights key issues impacting TCVs in clinical practice and reports on progress in development. We review the mechanism of action, immune-monitoring, dosing strategies, combinations, obstacles, and regulation of cancer vaccines. Most trials of personalized TCVs are ongoing and represent diverse platforms with predominantly early investigations of mRNA, DNA, or peptide-based targeting strategies against neoantigens in solid tumors, with many in combination immunotherapies. Multiple delivery systems, routes of administration, and dosing strategies are used. Intravenous or intramuscular administration is common, including delivery by lipid nanoparticles. Absorption and biodistribution impact antigen uptake, expression, and presentation, affecting the strength, speed, and duration of immune response. The emerging trials illustrate the complexity of developing this class of innovative immunotherapies. Methodical testing of the multiple potential factors influencing immune responses, as well as refined quantitative methodologies to facilitate optimal dosing strategies, could help resolve uncertainty of therapeutic approaches. To increase the likelihood of success in bringing these medicines to patients, several unique development challenges must be overcome.

Examining Socioeconomic and Computational Aspects of Vaccine Pharmacovigilance

BACKGROUND

Vaccine pharmacovigilance relates to the detection of adverse events, their assessment, understanding, and prevention, and communication of their risk to the public. These activities can be tedious and long lasting for regulatory authority scientists and may be affected by community practices and public health policies. To better understand underlying challenges, we examined vaccine adverse event reports, assessed whether data-driven techniques can provide additional insight in safety characterization, and wondered on the impact of socioeconomic parameters.

METHODS

First, we integrated VAERS content with additional sources of drug and molecular data and examined reaction and outcome occurrence by using disproportionality metrics and enrichment analysis. Second, we reviewed social and behavioral determinants that may affect vaccine pharmacovigilance aspects.

RESULTS

We describe our experience in processing more than 607000 vaccine adverse event reports and report on the challenges to integrate more than 95500 VAERS medication narratives with structured information about drugs and other therapeutics or supplements. We found that only 12.6% of events were serious, while 8.97% referred to polypharmacy cases. Exacerbation of serious clinical patient outcomes was observed in 8.88% VAERS cases in which drugs may interact with vaccinations or with each other, regardless of vaccine activity interference. Furthermore, we characterized the symptoms reported in those cases and summarized reaction occurrence among vaccine-types. Last, we examine socioeconomic parameters and cost-management features, explore adverse event reporting trends, and highlight perspectives relating to the use and development of digital services, especially in the context of personalized and collaborative health-care.

CONCLUSIONS

This work provides an informative review of VAERS, identifies challenges and limitations in the processing of vaccine adverse event data, and calls for the better understanding of the socioeconomic landscape pertaining vaccine safety concerns. We expect that adoption of computational techniques for integrated safety assessment and interpretation is key not only to pharmacovigilance practice but also to stakeholders from the entire healthcare system.

Did the New Italian Law on Mandatory Vaccines Affect Adverse Event Following Immunization's Reporting? A Pharmacovigilance Study in Southern Italy

Despite the well-recognized role of vaccines, coverage is far from optimal especially in children, representing a growing concern also in Italy. In order to reverse this emergency, the Italian Ministry approved in July 2017 the Law 119/2017, which renders mandatory and free of charge 10 vaccinations for patients aged 0–16. We aim to investigate the effects of the new Law 119/2017 on the reporting of adverse events following immunization related to mandatory vaccines into the Italian Pharmacovigilance database (Rete Nazionale di Farmacovigilanza – RNF). Therefore, we analyzed the spontaneous reports of suspected adverse events following immunization recorded in Campania Region (South of Italy) from December 1, 2016, to March 31, 2018. During the study period, 69 reports, covering 179 AEFIs, related to mandatory vaccines were sent to Campania Pharmacovigilance Regional Center. A substantial increase in AEFIs reporting was observed after the adoption of Law 119/2017. Out of 69 reports, 62% reported AEFIs that were considered as not serious and 78% had a favorable outcome. Out of 179 AEFIs, more than half referred to the following SOC: “general disorders and administration site conditions,” “nervous system disorders,” and “psychiatric disorders.” The highest number of reports came from patient/citizen. After the adoption of the Law 119/2017, there was an increase in the number of reports (18 before the adoption of the Law vs. 51 after). According to reported AEFIs during the entire period, no worrying safety data have emerged. In our opinion, the increase in the number of AEFIs’ reports should be related to the increase in vaccination coverage as well as to the intense debate that has followed the new Law. In this context, the continuous monitoring of vaccine safety and the fully implementation of vaccine–vigilance programs play a key role in achieving higher confidence in immunization programs and optimal vaccination coverage rate.

No signal of interactions between influenza vaccines and drugs used for chronic diseases: a case-by-case analysis of the vaccine adverse event reporting system and vigibase

BACKGROUND

An increasing number of reports indicates that vaccines against influenza may interact with specific drugs via drug metabolism. To date, actual impact of vaccine-drug interactions observed in the real world clinical practice has not been investigated.

METHODS

From VAERS and VigiBase, we collected Adverse Event Following Immunization (AEFI) reports for individuals receiving vaccines against influenza recorded as suspect and selected cases where predictable toxicity was recorded with oral anticoagulants, antiepileptics and statins (i.e. hemorrhages, overdosage and rhabdomyolysis, respectively). We applied AEFI and Drug Interaction Probability Scale (DIPS) Algorithms to assess causality of drug-vaccine interactions.

RESULTS

116 AEFI reports submitted to VAERS and 83 from Vigibase were included in our analysis; antiepileptics and statins were related to the highest number of indeterminate/consistent (93.7%; 65.3%) and possible/probable (50%; 57.7%) cases according to the AEFI and DIPS, respectively. The majority of cases occurred within the first week after vaccine administration (5-7 days).

CONCLUSION

The relative paucity of detected interactions does not impact on the benefit of the vaccination against influenza, which remains strongly recommended; this does not exclude that closer monitoring for selected patients exposed to concomitant chronic pharmacological therapies and affected by predisposing factors may be useful.

The Role of Cytochromes P450 in Infection

Cytochromes are expressed in many different tissues of the human body. They are found mostly in intestinal and hepatic tissues. Cytochromes P450 (CYPs) are enzymes that oxidize substances using iron and are able to metabolize a large variety of xenobiotic substances. CYP enzymes are linked to a wide array of reactions including and O-dealkylation, S-oxidation, epoxidation, and hydroxylation. The activity of the typical P450 cytochrome is influenced by a variety of factors, such as genus, environment, disease state, herbicide, alcohol, and herbal medications. However, diet seems to play a major role. The mechanisms of action of dietary chemicals, macro- and micronutrients on specific CYP isoenzymes have been extensively studied. Dietary modulation has effects upon the metabolism of xenobiotics. Cytochromes harbor intra- or interindividual and intra- or interethnic genetic polymorphisms. Bacteria were shown to express CYP-like genes. The tremendous metabolic activity of the microbiota is associated to its abundant pool of CYP enzymes, which catalyze phase I and II reactions in drug metabolism. Disease states, intestinal disturbances, aging, environmental toxic effects, chemical exposures or nutrition modulate the microbial metabolism of a drug before absorption. A plethora of effects exhibited by most of CYP enzymes can resemble those of proinflammatory cytokines and IFNs. Moreover, they are involved in the initiation and persistence of pathologic pain by directly activating sensory neurons and inflammatory cytokines.

Immunizations in Children Requiring Warfarin Therapy

Children with conditions requiring chronic warfarin therapy have increased. The importance of receiving immunizations in this population is magnified due to potential weakness in their immune response. There is concern about immunizing on therapeutic anticoagulation due to risk of hematomas and the influence of vaccine on warfarin metabolism. This study evaluated the influence of vaccines on warfarin effect as measured by the International Normalized Ratio and the clinically relevant hematomas or bruising postimmunization. There were no clinically relevant negative outcomes postimmunizations. This study demonstrates that immunizations may be safely administered to children receiving therapeutic warfarin therapy.

Risk of gastrointestinal complications associated to NSAIDs, low-dose aspirin and their combinations: Results of a pharmacovigilance reporting system

Gastrointestinal (GI) complications are one of the most limiting cause of use of NSAIDs. Beyond others well defined factors, history of peptic ulcer, older age, Helicobacter pylori infection and use of gastrotoxic drugs may affect their GI safety profile. In particular, the risk of GI complications associated to the use of antiplatelet drugs, especially low-dose acetylsalicylic acid (LDA) should deserve much attention. However, only few studies have focused on the effect of combination LDA/NSAIDs on the GI tract compared with the monotherapy and much less studies assessed this effect with multiple NSAIDs use. We aimed to characterize the GI safety profile of NSAIDs and LDA as monotherapy or their combinations in real-life conditions by analysing spontaneous adverse drug reactions (ADRs) reporting system in a Southern Italy. We used the case/non-case method in the Italian Pharmacovigilance Network (RNF). Cases were reports of GI events in the RNF between January 2007 and December 2011. Non-cases were all other reports during the same period. The association between NSAID and suspected GI ADRs was calculated using the reporting odds ratio (ROR) with 95% confidence intervals as a measure of disproportionality while adjusting for age, and concomitant use of antineoplastic agents or drugs for cardiovascular diseases. Sub-analysis were performed within the NSAID class. Among the 2816 adverse drug reactions recorded, we identified 374 (13.3%) cases of GI complications. Upper GI complications were the most frequently reported type of events. The highest associations were found for the combined use of NSAIDs and/or LDA, whilst the lowest associations were for their respective monotherapy. Looking at individual NSAIDs the highest association with GI events was observed for ketorolac exposure followed by nimesulide, diclofenac, aspirin, ketoprofen, and ibuprofen. This study highlights the primary role of the national spontaneous reporting system to bring out potential signals, such as the inappropriate drug use pattern, which however, have to be furtherly studied in-depth with ad hoc population-based studies.

Immunogenicity of meningococcal quadrivalent (serogroup A, C, W135 and Y) tetanus toxoid conjugate vaccine: systematic review and meta-analysis

Meningococcal meningitis represents one of the leading cause of bacterial meningitis in developed countries. Among the thirteen described serogroups, only five are usually responsible of invasive infections making immunisation against multiple serogroups the best strategy to protect individuals from this disease. Herein we carried out a systematic review and meta-analysis, in accordance with the PRISMA statement, of the recently EU-licensed meningococcal ACWY-tetanus toxoid conjugate vaccine (MenACWY-TT). We included 15 randomised clinical trials, comparing MenACWY-TT and Men-PS (ten studies), MenACWY-TT and MenC-CRM197 (four studies) and MenACWY-TT and MenACWY-DT (one study). All studies included in the meta-analysis showed high immunogenicity for MenACWY-TT vaccines in all tested serogroups. Our results suggest that the MenACWY-TT vaccine is as immunogenic as the other commercial available meningococcal vaccines.