[Source: The Lancet Infectious Diseases, full page: (LINK). Abstract, edited.]
Immunogenicity and safety of three aluminium hydroxide adjuvanted vaccines with reduced doses of inactivated polio vaccine (IPV-Al) compared with standard IPV in young infants in the Dominican Republic: a phase 2, non-inferiority, observer-blinded, randomised, and controlled dose investigation trial
Prof Luis Rivera, MD, Rasmus S Pedersen, PhD, Lourdes Peña, MD, Klaus J Olsen, PhD, Lars V Andreasen, PhD, Ingrid Kromann, BSc, Pernille I Nielsen, MSc, Charlotte Sørensen, MSc, Jes Dietrich, PhD, Ananda S Bandyopadhyay, MBBS, Birgit Thierry-Carstensen, MSc
Published: 25 April 2017 / Open Access / Article has an altmetric score of 1 / DOI: http://dx.doi.org/10.1016/S1473-3099(17)30177-9
Open access funded by Bill & Melinda Gates Foundation
© 2017 The Author(s). Published by Elsevier Ltd.
Cost and supply constraints are key challenges in the use of inactivated polio vaccine (IPV). Dose reduction through adsorption to aluminium hydroxide (Al) is a promising option, and establishing its effectiveness in the target population is a crucial milestone in developing IPV-Al. The aim of this clinical trial was to show the non-inferiority of three IPV-Al vaccines to standard IPV.
In this phase 2, non-inferiority, observer-blinded, randomised, controlled, single-centre trial in the Dominican Republic, healthy infants aged 6 weeks, not previously polio vaccinated, were allocated after computer-generated randomisation by block-size of four, to receive one of four IPV formulations (three-times reduced dose [1/3 IPV-Al], five-times reduced dose [1/5 IPV-Al], ten-times reduced dose [1/10 IPV-Al], or IPV) intramuscularly in the thigh at 6, 10, and 14 weeks of age. The primary outcome was seroconversion for poliovirus types 1, 2, and 3 with titres more than or equal to four-fold higher than the estimated maternal antibody titre and more than or equal to 8 after three vaccinations. Non-inferiority was concluded if the lower two-sided 90% CI of the seroconversion rate difference between IPV-Al and IPV was greater than −10%. The safety analyses were based on the safety analysis set (randomly assigned participants who received at least one trial vaccination) and the immunogenicity analyses were based on the per-protocol population. This study is registered with ClinicalTrials.gov registration, number NCT02347423.
Between Feb 2, 2015, and Sept 26, 2015, we recruited 824 infants. The per-protocol population included 820 infants; 205 were randomly assigned to receive 1/3 IPV-Al, 205 to receive 1/5 IPV-Al, 204 to receive 1/10 IPV-Al, and 206 to receive IPV. The proportion of individuals meeting the primary endpoint of seroconversion for poliovirus types 1, 2, and 3 was already high for the three IPV-Al vaccines after two vaccinations, but was higher after three vaccinations (ie, after completion of the expanded programme of immunisation schedule): 1/3 IPV-Al 98·5% (n=202, type 1), 97·6% (n=200; type 2), and 99·5% (n=204, type 3); 1/5 IPV-Al: 99·5% (n=204, type 1), 96·1% (n=197, type 2), and 98·5% (n=202, type 3); and 1/10 IPV-Al: 98·5% (n=201, type 1), 94·6% (n=193, type 2), and 99·5% (n=203, type 3). All three IPV-Al were non-inferior to IPV, with absolute differences in percentage seroconversion for each poliovirus type being greater than −10% (1/3 IPV-Al type 1, −1·46 [–3·60 to 0·10], type 2, −0·98 [–3·62 to 1·49], and type 3, −0·49 [–2·16 to 0·86]; 1/5 IPV-Al type 1, −0·49 [–2·16 to 0·86], type 2, −2·45 [–5·47 to 0·27], and type 3, −1·46 [–3·60 to 0·10]; and 1/10 IPV-Al type 1, −1·47 [–3·62 to 0·10], type 2, −3·94 [–7·28 to −0·97], and type 3, −0·49 [–2·17 to 0·86]). Three serious adverse events occurred that were unrelated to the vaccine.
The lowest dose (1/10 IPV-Al) of the vaccine performed well both after two and three doses. Based on these results, this new vaccine is under investigation in phase 3 trials.
Bill & Melinda Gates Foundation.
Keywords: Vaccines; Poliovirus; Poliomyelitis.