Supplementary Materials to the Manuscript

Supplementary materials to the manuscript:

ASSESSMENT OF IMMUNE RESPONSES TO H5N1 INACTIVATED INFLUENZA VACCINE AMONG INDIVIDUALS PREVIOUSLY PRIMED WITH H5N2 LIVE ATTENUATED INFLUENZA VACCINE

Larisa Rudenko1, Anatoly Naykhin1, Svetlana Donina1, Daniil Korenkov1, Galina Petukhova1, Irina Isakova-Sivak1, Igor Losev1, Marina Stukova2, Mariana Erofeeva2, Alexandra Nikiforova3, Maureen Power4 and Jorge Flores4

1Institute of Experimental Medicine, Saint Petersburg, Russia; 2Research Institute of Influenza, Saint Petersburg, Russia; 3Department of Preclinical Trials, Microgen, Moscow, Russia; 4PATH, Seattle, WA, USA

Safety of the A(H5N1) inactivated influenza vaccine given to naïve subjects and individuals previously primed with A(H5N2) LAIV.

The A(H5N1) IIV was well tolerated by both study groups, with no clinically significant safety signals detected after one or two vaccine doses. No immediate adverse reactions were reported within the first two hours post vaccination. No local reactions occurred over the 28 days after each dose in both study groups (Table S1). One mild solicited systemic reaction (headache) was recorded in a single subject from the primed group after the first dose. Unsolicited adverse events were similar between study groups (68.4% of subjects after dose 1 and 47.4% after dose 2 in the primed group and 62.5% of subjects after dose 1 and 16.7% after dose 2 in the control group). The most frequent unsolicited adverse events observed following vaccination consisted of mild laboratory chemistry abnormalities, which were generally similar in frequency between treatment groups (Table S2). Importantly, no serious adverse events were reported in either study group after one or two doses of the A(H5N1) IIV. These data suggest that previous exposure to the A(H5N2) LAIV did not increase reactogenicity of the A(H5N1) IIV given intramuscularly 1.5 years later.

1 N= total number of subjects, 2 number of subjects with event, % and CI, 95% confidence interval as calculated by Wilson test

Table S2. Subjects with adverse events following vaccination with A(H5N1) IIV

* moderate grade in one subject;

1 N= total number of subjects, 2 number of subjects with event, % and CI, 95% confidence interval as calculated by Wilson test; ALT – alanine aminotransferase; AAT – aspartate aminotransferase.

Statistical analyses of the HAI and MN antibody immune responses in LAIV-primed and naïve volunteers after immunization with two doses of A(H5N1) inactivated influenza vaccine

P values for the differences in GMT levels between the primed and control groups were calculated by the Mann-Whitney U test (log2-transformed titers were used for the analysis);

P values for the differences in proportions of subjects between the primed and control groups were calculated by the Fisher exact test, two-tailed.

Table S3. Statistical analyses of antibody immune responses (comparison of the primed and control groups)

17/t/Tur (H5N2): А/17/turkey/Turkey/05/133 (H5N2) LAIV strain; NIBRG-23 (H5N1): А/turkey/Turkey/5/05 (H5N1) PR8-based candidate vaccine virus; Indo (H5N1): A/Indonesia/5/2005 (H5N1) PR8-based candidate vaccine virus; d/Pot (H5N2): A/17/duck/Potsdam/86/92 (H5N2) LAIV strain.

statistically significant differences are shown in bold (p<0.05).