0%) versus 9/488 (1.8%) for pertussis toxin; 0/500 (0%) versus 0/496 (0%) for FHA; and 0/503 versus 1/498 for PRN, respectively. Also, comparable percentages of subjects achieved a 4-fold rise for at least two of the three pertussis antigens (i.e., 86% for concomitant Tdap versus 88% for Tdap alone). Similar findings have been reported from three other studies on concomitant use of quadrivalent meningococcal conjugate

vaccines in adolescents [22], Idelalisib purchase [23] and [24] as well as a study of Tdap concomitantly administered with influenza vaccine [25]. In the latter study, the ‘Tdap alone’ group received the vaccine 1 month after influenza vaccine and lower titres were observed for all antigens (non-inferiority criteria missed for PRN only) in the group receiving the Tdap concomitantly with influenza vaccine. The study did not include a group receiving Tdap prior to influenza vaccine so an alternative interpretation might have been, as demonstrated in our study, that sequential administration of Tdap after influenza vaccine enhanced the responses to the pertussis antigens. The immune responses to HPV when given concomitantly or sequentially SCH 900776 mw with MenACWY-CRM and Tdap were non-inferior for all four HPV types when seroconversion and GMTs were used as the endpoints. Similar results were recorded in a study that examined the co-administration of HPV and hepatitis B vaccine in subjects

16–23 years of age [15]. Higher

post-vaccination HPV GMTs were recorded in males and also in younger subjects (11–14 years of age), which is consistent with data reported from other studies which did not include concomitant vaccine use (data not shown) [26], [27] and [28]. Previous studies have shown MenACWY-CRM to be a well-tolerated and immunogenic vaccine with the potential to provide broad meningococcal disease protection from infancy through to adulthood. The development of this vaccine builds upon a history of successful glycoconjugate vaccines using CRM as the carrier protein, including pneumococcal, Haemophilus influenzae type b (Hib) disease, and serogroup C meningococcal conjugate vaccines. The results from this study further demonstrate that MenACWY-CRM is well GPX6 tolerated in adolescents and that concomitant or sequential administration of MenACWY-CRM with HPV or Tdap vaccines does not result in increased reactogenicity or a clinically relevant impact on immune responses for any of the vaccines. This is the first published report of concomitant administration of three recommended adolescent vaccines – Tdap, HPV, and an investigational quadrivalent meningococcal conjugate – and it supports concomitant administration of these vaccines to enhance timely and comprehensive vaccination coverage and, hence, protection against several serious diseases in adolescents. The trial was funded and conducted by Novartis Vaccines.