Table 3.
Ongoing research on current and future tools for polio eradication
| Research Question/Tool | Importance | Status |
|---|---|---|
| Current tools | ||
| Combination schedules of IPV and OPV | Understand role of IPV and bOPV when used together in recommended schedules in developing countries | Immunogenicity (humoral and intestinal) of ≥1 IPV dose combined with bOPV in 6–10–14 wk mixed schedules (Colombia-Dominican Republic-Guatemala-Panama, India, Bangladesh) Immunogenicity (humoral and intestinal) of IPV / bOPV in 2-4-6 mo sequential regimen (Chile) Duration of protection of boosting of intestinal immunity induced by IPV in OPV primed populations (India) |
| Fractional doses of IPV | Reduced cost | Immunogenicity with fractional IPV doses via ID route (The Gambia, Bangladesh) |
| New tools | ||
| Immunogenicity of monovalent IPV-2 (m-IPV2) | Improved humoral and intestinal immunogenicity Reduced cost with 1 dose of m-IPV2 |
Phase I (Belgium) study on safety completed Phase II (Panama) study underway to evaluate safety and immunogenicity |
| Immunogenicity of IPV adjuvants | Reduced cost Increased supply Potential for enhanced mucosal immunity |
Clinical studies being planned to evaluate potential for aluminum salts adjuvants and for dmLT (double-mutant heat-labile enterotoxin) adjuvants for IPV |
| Feasibility of novel routes of administration | Operational advantages Potential for use in SIAs Concomitant use with other vaccines |
Studies in humans being planned or implemented to evaluate impact of IM (Intramuscular) and ID (Intradermal) delivery of IPV through use of disposable jet injectors, microneedle patch, and other novel delivery techniques |
| Development of genetically stable OPV and attenuated IPV seed strains | Potential use in outbreak control (reduced risk of VDPVs and VAPP) or in routine immunization if IPV is considered inadequate in reducing transmission risk Further attenuated and less infectious seed strains for safe IPV manufacture |
In preclinical development or planning phase |
| Immunogenicity with Sabin IPV | Minimize risk of reintroduction of WPV from IPV manufacturing facilities | Sabin IPV has been licensed in Japan Efficacy and feasibility of large-scale production are currently being evaluated |
Adapted from Bandyopadhyay AS, Garon J, Seib K, et al. Polio vaccination: past, present and future. Future Microbiol 2015;801–2. http://dx.doi.org/10.2217/fmb.15.19.