Safety and immunogenicity of SIIPL Tdap, a new tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine, in healthy subjects 4-65 years of age: A Phase II/III randomized, observer-blinded, active controlled, multicenter clinical study in Germany

Inci Aydin; Marcus May; Fabio Pisano; Nontsikelelo Mpofu-Maetzig; Leander Grode; Sameer Parekh; Pramod Pujari; Sunil Shewale; Shivani Desai; Hitt Sharma; Harish Rao; Manish Gautam; Sunil Gairola; Umesh Shaligram

doi:10.1016/j.vaccine.2023.09.060

Safety and immunogenicity of SIIPL Tdap, a new tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine, in healthy subjects 4-65 years of age: A Phase II/III randomized, observer-blinded, active controlled, multicenter clinical study in Germany

Vaccine. 2023 Oct 10:S0264-410X(23)01157-X. doi: 10.1016/j.vaccine.2023.09.060. Online ahead of print.

Authors

Affiliations

¹ Serum Life Science Europe GmbH, Hannover, Germany. Electronic address: aydin@sls-eu.com.
² Serum Life Science Europe GmbH, Hannover, Germany.
³ Serum Life Science Europe GmbH, Hannover, Germany. Electronic address: pisano@sls-eu.com.
⁴ Serum Institute of India Private Limited, Pune, India.

PMID: 37827966
DOI: 10.1016/j.vaccine.2023.09.060

Abstract

Background: This study assessed the safety and immunogenicity of a new booster vaccine against tetanus, diphtheria, and pertussis manufactured by Serum Institute of India Pvt. Ltd (SIIPL Tdap).

Methods: The Phase II/III trial was randomized (2:1), observer blinded and active controlled. Healthy subjects aged 4-65 years received a single dose of either SIIPL Tdap or comparator Tdap vaccine (Boostrix®, GlaxoSmithKline, Belgium), and were followed-up for 30 days. Blood samples for safety and immunogenicity assessments were collected pre-vaccination and on day 30 post-vaccination. The study assessed safety and reactogenicity of SIIPL Tdap compared to the comparator Tdap as well as the co-primary immunogenicity outcomes: (i) seroprotection rates against diphtheria toxoid (DT) and tetanus toxoid (TT) and (ii) the booster response rates against pertussis toxoid (PT), filamentous hemagglutinin (FHA) and pertactin (PRN) 30 days post-vaccination in all study subjects. A margin of -10 % was used for non-inferiority testing. Secondary outcomes included the booster response rates against DT and TT, seropositivity rates against pertussis antigens, and antibody geometric mean concentrations (GMCs) for all vaccine components.

Results: At Day 30 post-vaccination, SIIPL Tdap was assessed as non-inferior to the comparator Tdap in terms of: i) seroprotection rates against DT (94.4 % vs. 94.9 %) and TT (99.9 % vs. 100 %) and ii) pertussis booster response rates (93.8 % vs. 88.4 % anti-PT, 89.7 % vs. 90.9 % anti-FHA and 86.3 % vs. 84.4 % anti-PRN), for SIIPL Tdap versus comparator Tdap, respectively. GMCs for anti-PT and anti-PRN were higher in subjects vaccinated with SIIPL Tdap compared to comparator Tdap. All other secondary outcomes were comparable. The overall frequency of local and systemic solicited AEs was comparable; no treatment related SAEs were reported.

Conclusions: Booster vaccination with SIIPL Tdap was non-inferior to comparator Tdap with respect to the immunogenicity of the vaccine components and was equally well tolerated. EudraCT number: 2019-002706-46.

Keywords: Acellular pertussis; Booster; Diphtheria; Tetanus; Vaccine.