Randomized controlled clinical trial of fractional doses of inactivated poliovirus vaccine administered intradermally by needle-free device in Cuba.
BACKGROUND
As part of an evaluation of strategies to make inactivated poliovirus vaccine (IPV) affordable for developing countries, we conducted a clinical trial of fractional doses of IPV in Cuba.


METHODS
We compared the immunogenicity and reactogenicity of fractional-dose IPV (0.1 mL, or 1/5 of a full dose) given intradermally using a needle-free jet injector device compared with full doses given intramuscularly. Subjects were randomized at birth to receive IPV at 6, 10, and 14 weeks.


RESULTS
A total of 471 subjects were randomized to the 2 study groups, and 364 subjects fulfilled the study requirements. No significant differences at baseline were detected. Thirty days after completing the 3-dose schedule of IPV, 52.9%, 85.0%, and 69.0% of subjects in the fractional-dose IPV arm seroconverted for poliovirus types 1, 2, and 3, respectively, whereas 89.3%, 95.5%, and 98.9% of subjects in the full-dose IPV arm seroconverted for poliovirus types 1, 2, and 3, respectively (all comparisons, P < .001). The median titers of each poliovirus serotype were significantly lower in the intradermal arm than in the intramuscular arm (P < .001). Only minor local adverse effects and no moderate or serious adverse events were reported.


CONCLUSIONS
This large-scale evaluation demonstrates the feasibility of fractional doses of IPV given intradermally as an antigen-sparing strategy but also shows that IPV given to infants at 6, 10, and 14 weeks of age results in suboptimal immunogenicity (especially for the fractional-dose arm).
Resik
Sonia
S
Pedro Kouri Institute, Havana, Cuba.
Tejeda
Alina
A
Lago
Pedro Mas
PM
Diaz
Manuel
M
Carmenates
Ania
A
Sarmiento
Luis
L
Alemañi
Nilda
N
Galindo
Belkis
B
Burton
Anthony
A
Friede
Martin
M
Landaverde
Mauricio
M
Sutter
Roland W
RW
D003462:Cuba; D004306:Dose-Response Relationship, Immunologic; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D007223:Infant; D007273:Injections, Intramuscular; D007277:Injections, Jet; D008297:Male; D011051:Poliomyelitis / Q000276:immunology / Q000517:prevention & control; D011054:Poliovirus Vaccine, Inactivated / Q000008:administration & dosage* / Q000276:immunology
D011054:Poliovirus Vaccine, Inactivated