Closely held PharmaJet has highlighted a peer-reviewed publication in the AI-powered open science publishing platform Qeios, which evaluated the evidence on implementation of novel technologies for intradermal (ID) delivery of fractional-dose inactivated polio vaccine (fIPV).
The publication titled A Narrative Review and Perspective on Implementation Research on Intradermal Delivery Methods for Fractionated-Dose Inactivated Poliomyelitis Vaccine, examined available ID delivery options, associated implementation challenges and benefits, and the potential for broader application of ID delivery across additional vaccines, including rabies, malaria, and monkeypox (mpox).
Recent trends in vaccination policy, as seen in the Global Polio Eradication Initiative and the mpox pandemic, have reinforced that vaccine administration to the dermis (ID) is a valuable alternative to intramuscular administration with needles. However, traditional ID delivery using needles (the Mantoux technique), remains challenging to implement at scale due to the technical difficulty of administration and the extensive training required to ensure consistent dose accuracy and injection depth. Operational constraints have hindered the broader adoption of ID vaccination, particularly in settings with healthcare workforce constraints. This highlights the need for alternative technologies that reduce training burden, improve safety and efficiency, and, above all, improve the user and patient experience, an important success factor in any vaccination setting.
To assess the performance of novel ID delivery approaches, a literature search was conducted using PubMed to identify relevant publications between January 2015 and June 2024 using the terms “inactivated polio vaccine” and “intradermal delivery”. Of the 59 publications identified, 14 met the criteria for original studies in human subjects using novel delivery methods for ID administration of commercially available fIPV vaccines. Evaluated delivery methods included needle-free injectors, microneedle-based technologies, and needle adapters. The authors found that the most reported implementation factors included child’s distress associated with injection; acceptability (preference) with vaccinators; acceptability (preference) with caregivers; immunization coverage; training requirements and adequacy; vaccine wastage; ergonomics; acceptability among adult recipients; and feasibility.
As the only commercialized, WHO-prequalified ID technology in the review, Tropis was uniquely identified to improve campaign and routine immunization coverage, reduce total immunization costs, decrease training and administration time, and achieve high levels of acceptability with caretakers and healthcare workers. 2,3 Unlike micro-array patches, Tropis has the advantage of compatibility with traditional vaccine vial presentations without the need for reformulation. In reference to endemic country use, WHO has noted that the use of fIPV is well-supported in specific areas where the deployment of injectors can improve vaccine demand and enhance overall coverage with both oral polio vaccine (OPV) and inactivated polio vaccine (IPV).
In a statement, Paul LaBarre, Senior Vice President – Global Business Development, PharmaJet, commented, “Tropis is commercially available and has demonstrated its ability to perform efficiently in large scale campaigns, with more than 20 million Needle-free Tropis Syringes provided to date for campaigns and supplemental immunization activities across Asia and Africa. With compelling data supporting improved coverage, cost savings, and high acceptability, we are seeing increased interest in expanded use of Tropis in polio vaccine programs and for new applications such as mpox and rabies immunization.”
