Assessing vaccine introduction and uptake timelines in Gavi-supported countries: are introduction timelines accelerating across vaccine delivery platforms?

Abstract

Background: Previous studies identified factors influencing regulatory approval to introduction timelines for individual vaccines. However, introduction and uptake timelines have not been comprehensively assessed across the portfolio of Gavi-supported vaccines.

Methods: We analysed median times between introduction milestones from vaccine licensure to country introduction and uptake across six vaccine-preventable diseases (VPDs), three delivery platforms and 69 Gavi-supported countries. Data were gathered from public, partner and manufacturer records. VPDs and prequalified vaccines analysed included Haemophilus influenzae type b (DTwP-HepB-Hib, pentavalent), pneumococcal disease (pneumococcal conjugate vaccine, PCV), rotavirus diarrhoea (rotavirus vaccine, RVV), cervical cancer (human papillomavirus vaccine, HPV), polio (inactivated polio vaccine, IPV) and meningococcal meningitis (meningococcal group A conjugate vaccine, MenA).

Results: Median time from first vaccine licensure to first Gavi-supported country introduction across VPDs at a 'global level' (Gavi-supported countries) was 5.4 years. Once licensed, MenA vaccines reached first introduction fastest (campaign=0.6 years; routine immunisation (RI)=1.7 years). Most introductions were delayed. Country uptake following first introduction was accelerated for more recently Gavi-supported RI vaccines compared with older ones.

Conclusion: Factors accelerating timelines across delivery platforms included rapid product prequalifications by WHO, strong initial recommendations by the WHO Strategic Advisory Group of Experts (SAGE) on Immunization, achieving target product profiles on first vaccine licensure within a VPD and completing several VPD milestones at a global level prior to licensure. Milestones required for introduction in Gavi-supported countries should start prior or in parallel to licensure to accelerate uptake of vaccines delivered through diverse delivery platforms.

Keywords: health policy; health systems; immunisation; vaccines.

Figure 1

Chronological milestone order and times between milestones for all global-level VPDs, and time from first global-level VPD milestone to first country introduction for all VPDs. Licensure=1st WHO-approved NRA licensure per VPD; SAGE=1st SAGE recommendation; Gavi=Gavi Board approval; PQ=1st WHO prequalified vaccine by VPD; UNICEF=Unicef tender issued; Intro=1st Gavi-supported country introduction; excludes time to target coverage (DTP3) rate reached because only Pentavalent and PCV reached 50% of target coverage (DTP3) rate milestone. Abbreviations: HPV, human papillomavirus vaccine; MenA, meningococcal group A conjugate vaccine; NRA, national regulatory authority; PCV, pneumococcal conjugate vaccine; Penta, pentavalent vaccine; RVV, rotavirus vaccine; SAGE, WHO Strategic Advisory Group of Experts on Immunization; VPD, vaccine-preventable disease.

Figure 2

Country-level introduction milestone data across all country introductions and VPDs. Country-level introduction milestone data across country introductions of pentavalent, PCV (all), RVV, IPV, HPV (national), HPV (RI), MenA (C), MenA (RI) vaccines. Pentavalent and PCV experienced the greatest variation in introduction timelines across Gavi-supported countries. Abbreviations: HPV, human papillomavirus vaccine; IPV, inactivated polio vaccine; MenA, meningococcal group A conjugate vaccine; PCV, pneumococcal conjugate vaccine; RI, routine immunisation; RVV, rotavirus vaccine; VPD, vaccine-preventable disease.

Figure 3

Projected introduction timelines compared with actual introduction timelines. Projected introduction timelines vs actual introduction timelines as stated in Gavi funding applications. The majority of countries introduced after their projected introduction date in the Gavi funding application across all VPDs. Abbreviations: HPV, human papillomavirus vaccine; IPV, inactivated polio vaccine; MenA, meningococcal group A conjugate vaccine; PCV, pneumococcal conjugate vaccine; Penta, pentavalent vaccine; RI, routine immunisation; RVV, rotavirus vaccine; VPD, vaccine-preventable disease.

Figure 4

Progress towards reaching target coverage rates by routine immunisation vaccines. Cumulative percentage of Gavi countries reaching target coverage rate (ie, once a country is within 10% of the country’s own DTP3 rate) each year for pentavalent vaccines (Penta, Hib3 coverage), rotavirus vaccines (RVV, RVV last dose coverage), pneumococcal conjugate vaccines (PCV, PCV3 coverage) and inactivated polio vaccines (IPV, IPV first dose) across all Gavi countries from first licensed vaccine (A), first WHO prequalified vaccine (B) and from first Gavi-supported introduction (C). Progress in reaching target coverage rate for pentavalent vaccines (Penta, Hib3 coverage), rotavirus vaccines (RVV, RVV last dose coverage), pneumococcal conjugate vaccines (PCV, PCV3 coverage) and inactivated polio vaccines (IPV, IPV first dose) across the entire Gavi surviving infant cohort from first licensed vaccine (D), first WHO prequalified vaccine (E) and from first Gavi-supported introduction (F). IPV data are excluded from A, B, D and E given IPV was not included in global-level VPD analysis. PCV data separated out in A and D as the timeline for PCV10 and PCV13 vaccines differed from the timeline for PCV7.