id	author	title	date	pages	extension	mime	words	sentences	flesch	summary	cache	txt
cord-285128-48l1w65p	Custers, Jerome	Vaccines based on replication incompetent Ad26 viral vectors: standardized template with key considerations for a risk/benefit assessment	2020-10-03		.txt	text/plain	4728	295	39	A replication incompetent adenoviral vector based on human adenovirus type 26 (Ad26) has been evaluated in several clinical trials. Clinical trials have not shown meaningful impact of pre-existing immunity to Ad26 on vaccine immunogenicity, even in the presence of Ad26 neutralizing antibody titers or Ad26-targeting T cell responses at baseline. For example, a seroprevalence study of the 51 human adenovirus serotypes known at the time showed that several serotypes from particularly subgroups B and D, including Ad26, were rare in a Belgian population (3) , suggesting that vectors (rAd) derived from these serotypes might be useful alternatives to Ad5-based vectors for vaccine development, since for Ad5-based vectors it was shown that their high prevalence hampered their clinical use (4) (5) (6) (7) (8) . What is known about the effect of pre-existing immunity, including both natural immunity and repeat administration of the vector or the vaccine, on 'take', safety or efficacy in any animal model or human studies using this vector?	./cache/cord-285128-48l1w65p.txt	./txt/cord-285128-48l1w65p.txt