Dissolvable microneedle patches for the influenza vaccine are tolerated just as well as vaccinations delivered by a needle or syringe, according to a study published in the Lancet. Microneedle patches provide simplicity, cost-effectiveness, acceptability, and safety.
This partly blinded, placebo-controlled randomized study was conducted in 2015 at Emory University. It included non-pregnant, immunocompetent adults age 18 to 49 who were naïve to the 2014-2015 flu vaccine. They were randomly assigned to 1 of 4 groups: they received a single dose of inactivated influenza vaccine (fluvirin: 18 μg of haemagglutinin per H1N1 vaccine strain) 17 μg of haemagglutinin per H3N2 vaccine strain, and 15 μg of haemagglutinin per B vaccine strain) either by an unmasked healthcare worker either via (1) microneedle patch, (2) intramuscular injection, (3) placebo via microneedle patch, or (4) self-administration of inactivated vaccine by microneedle patch.
The participants were not blinded to the method of vaccination. The primary safety outcome measures included adverse events within 180 days related to the study product, grade 3 solicited or unsolicited adverse events in 28 days, and solicited injection site and reactogenicity up to 7 days after administration. Chronic illness within 180 days and unsolicited adverse events within 28 days were considered secondary safety outcomes.
There were 100 participants enrolled and assigned to each group. In the 3 vaccinated groups — administered by a healthcare worker via microneedle patch or intramuscular injection or self-administered microneedle patch — had overall solicited adverse events of n=89, n=73, and n=73, respectively, and unsolicited adverse events of n=18, n=12, and n=14, respectively.
After intramuscular injection in 25 participants, reactogenicity was mild, transient, and commonly reported as tenderness in 15 (60%) participants (95% CI, 39-79) and pain in 11 (44%) (95% CI, 24-65). After administration via microneedle patch, adverse events in 50 participants were reported as tenderness in 33 (66%) patients (95% CI, 51-79), erythema in 20 (40%) (95% CI, 26-55), and pruritus in 41 (82%) (95% CI, 69-91).
Rouphael NG, Paine M, Mosley R, et al. The safety, immunogenicity, and acceptability of inactivated influenza vaccine delivered by microneedle patch (TIV-MNP 2015): a randomised, partly blinded, placebo-controlled, phase 1 trial. Lancet. 2017;390(10095): 649-658.