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Pfizer–BioNTech COVID-19 vaccine
Type of vaccine for humans / From Wikipedia, the free encyclopedia
The Pfizer–BioNTech COVID-19 vaccine, sold under the brand name Comirnaty,[2][32] is an mRNA-based COVID-19 vaccine developed by the German biotechnology company BioNTech. For its development, BioNTech collaborated with the American company Pfizer to carry out clinical trials, logistics, and manufacturing.[44][45] It is authorized for use in humans to provide protection against COVID-19, caused by infection with the SARS-CoV-2 virus.[2][30] The vaccine is given by intramuscular injection.[34] It is composed of nucleoside-modified mRNA (modRNA) that encodes a mutated form of the full-length spike protein of SARS-CoV-2, which is encapsulated in lipid nanoparticles.[46] Initial guidance recommended a two-dose regimen, given 21 days apart;[34][47][48][49] this interval was subsequently extended to up to 42 days in the United States,[34][50] and up to four months in Canada.[51][52]
Clinical trials began in April 2020;[47] by November 2020, the vaccine had entered phase III clinical trials, with over 40,000 people participating.[53] Interim analysis of study data showed a potential efficacy of 91.3% in preventing symptomatic infection within seven days of a second dose and no serious safety concerns.[49][54] Most side effects are mild to moderate in severity and resolve within a few days.[2][55] Common side effects include mild to moderate pain at the injection site, fatigue, and headaches.[56][57] Reports of serious side effects, such as allergic reactions, remain very rare[lower-alpha 1] with no long-term complications documented.[2][59]
The vaccine is the first COVID‑19 vaccine to be authorized by a stringent regulatory authority for emergency use[60][61] and the first to be approved for regular use.[41] In December 2020, the United Kingdom was the first country to authorize its use on an emergency basis.[59] It is authorized for use at some level in the majority of countries.[62][63][64][65] On 23 August 2021, the Pfizer–BioNTech vaccine became the first COVID-19 vaccine to be approved in the US by the Food and Drug Administration (FDA).[29][32][66] The logistics of distributing and storing the vaccine present significant challenges due to the requirement for its storage at extremely low temperatures.[67]
In August 2022, a bivalent version of the vaccine (Pfizer-BioNTech COVID-19 Vaccine, Bivalent) was authorized for use as a booster dose in individuals aged twelve and older in the US.[68][69][70][71] The following month, the BA.1 version of the bivalent vaccine (Comirnaty Original/Omicron BA.1 or tozinameran/riltozinameran)[72] was authorized as a booster for use in the UK.[73][74][75] The same month, the European Union authorized both the BA.1 and the BA.4/BA.5 (tozinameran/famtozinameran) booster versions of the bivalent vaccine.[2][3][40]