Prevenar 20 est un vaccin pneumococcique destin\u00e9 \u00e0 la pr\u00e9vention, chez l\u2019adulte et l\u2019enfant \u00e0 partir de 6 semaines, des pneumonies et des infections invasives dues \u00e0 Streptococcus pneumoniae, ainsi que des otites moyennes aigu\u00ebs chez les enfants de 6 semaines \u00e0 17 ans. Il n\u2019est disponible que sur prescription m\u00e9dicale. L\u2019administration se fait par injection intramusculaire : dans la cuisse chez le nourrisson et dans le haut du bras chez l\u2019enfant plus grand, l\u2019adolescent et l\u2019adulte. Chez l\u2019adulte, une seule injection est pr\u00e9vue ; chez l\u2019enfant et l\u2019adolescent, le nombre d\u2019injections d\u00e9pend de l\u2019\u00e2ge et du statut vaccinal ant\u00e9rieur, selon un sch\u00e9ma d\u00e9fini dans le r\u00e9sum\u00e9 des caract\u00e9ristiques et la notice.<\/p>\n
Le vaccin contient des polysaccharides capsulaires purifi\u00e9s de 20 s\u00e9rotypes de S. pneumoniae, conjugu\u00e9s \u00e0 une prot\u00e9ine porteuse pour renforcer la r\u00e9ponse immunitaire, et adsorb\u00e9s sur un adjuvant \u00e0 base d\u2019aluminium. Le m\u00e9canisme d\u2019action repose sur l\u2019induction d\u2019anticorps dirig\u00e9s contre ces polysaccharides, permettant une r\u00e9ponse plus rapide et plus efficace en cas d\u2019exposition ult\u00e9rieure aux bact\u00e9ries correspondantes.<\/p>\n
Les donn\u00e9es d\u2019efficacit\u00e9 reposent principalement sur des \u00e9tudes immunologiques comparatives chez l\u2019adulte. Dans deux \u00e9tudes principales, Prevenar 20 a induit des r\u00e9ponses immunitaires jug\u00e9es comparables \u00e0 celles de deux vaccins pneumococciques d\u00e9j\u00e0 autoris\u00e9s : Prevenar 13 (ciblant 13 s\u00e9rotypes) et Pneumovax 23 (ciblant 23 s\u00e9rotypes). Ensemble, Prevenar 13 et Pneumovax 23 couvrent les 20 s\u00e9rotypes contenus dans Prevenar 20. La protection de Prevenar 20 contre les maladies pneumococciques est ainsi inf\u00e9r\u00e9e \u00e0 partir de l\u2019efficacit\u00e9 connue de ces vaccins de r\u00e9f\u00e9rence, ce qui constitue un point important de contexte pour l\u2019\u00e9valuation r\u00e9glementaire et la surveillance des politiques vaccinales.<\/p>\n
Dans une \u00e9tude men\u00e9e chez environ 3 000 personnes \u00e2g\u00e9es de 60 ans et plus, les participants ont re\u00e7u soit Prevenar 20, soit une s\u00e9quence Prevenar 13 puis Pneumovax 23 \u00e0 un mois d\u2019intervalle. Un mois apr\u00e8s chaque vaccination, les niveaux d\u2019anticorps \u00e9taient globalement comparables entre les deux groupes pour tous les s\u00e9rotypes de Prevenar 20 sauf un, ce qui sugg\u00e8re une non\u2011inf\u00e9riorit\u00e9 immunologique pour la majorit\u00e9 des s\u00e9rotypes cibl\u00e9s. Cette approche comparative avec des vaccins d\u00e9j\u00e0 en usage constitue un \u00e9l\u00e9ment central pour les autorit\u00e9s sanitaires dans la d\u00e9cision d\u2019autorisation, de recommandation et de suivi d\u2019un \u00e9ventuel d\u00e9ploiement.<\/p>\n
Les principaux enjeux de politique publique portent sur la pr\u00e9vention des infections invasives et des pneumonies d\u2019origine pneumococcique chez des populations larges (adultes, personnes \u00e2g\u00e9es, enfants et adolescents), sur la place de ce vaccin dans les strat\u00e9gies de vaccination existantes par rapport \u00e0 Prevenar 13 et Pneumovax 23, et sur le suivi de l\u2019efficacit\u00e9 et de la s\u00e9curit\u00e9 en vie r\u00e9elle. Les informations disponibles mettent en avant des r\u00e9sultats immunologiques, mais ne d\u00e9taillent pas dans ce segment les r\u00e9sultats cliniques (r\u00e9duction de cas de maladie) ni les donn\u00e9es de tol\u00e9rance, ce qui constitue une limite \u00e0 prendre en compte pour l\u2019analyse des impacts potentiels sur les politiques de sant\u00e9. (contenu r\u00e9sum\u00e9 en fran\u00e7ais par l’IA)\u00a0\u200bLire la Suite<\/a><\/p>","protected":false},"excerpt":{"rendered":" Prevenar 20 est un vaccin pneumococcique destin\u00e9 \u00e0 la pr\u00e9vention, chez l\u2019adulte et l\u2019enfant \u00e0 partir de 6 semaines, des pneumonies et des infections invasives dues \u00e0 Streptococcus pneumoniae, ainsi […]<\/p>\n","protected":false},"author":1,"featured_media":17698,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[7],"tags":[257,227,226],"class_list":["post-21576","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-medicaments-et-produits-de-sante","tag-ema","tag-ia","tag-sources-etrangeres"],"_links":{"self":[{"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/posts\/21576","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=21576"}],"version-history":[{"count":0,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/posts\/21576\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=\/wp\/v2\/media\/17698"}],"wp:attachment":[{"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=21576"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=21576"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/veilles-affaires-sociales.fr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=21576"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}