tetano
Editor, Senior Moderator
Vaccine
. 2023 Dec 1:S0264-410X(23)01396-8.
doi: 10.1016/j.vaccine.2023.11.050. Online ahead of print. Safety and immunogenicity of locally produced trivalent inactivated influenza vaccine (Tri Fluvac) in healthy Thai adults aged 18-64 years in Nakhon Phanom: A Phase III double blinded, three-arm, randomized, controlled trial
Kriengkrai Prasert[SUP] 1 [/SUP], Prabda Praphasiri[SUP] 2 [/SUP], Hatairat Lerdsamran[SUP] 3 [/SUP], Sutthichai Nakphook[SUP] 4 [/SUP], Darunee Ditsungnoen[SUP] 5 [/SUP], Sutthinan Chawalchitiporn[SUP] 6 [/SUP], Kanlaya Sornwong[SUP] 6 [/SUP], Kittisak Poopipatpol[SUP] 7 [/SUP], Ponthip Wirachwong[SUP] 7 [/SUP], Piengthong Narakorn[SUP] 7 [/SUP], Somchaiya Surichan[SUP] 7 [/SUP], Nava Suthepakul[SUP] 7 [/SUP], Napawan Thangsupanimitchai[SUP] 7 [/SUP], Chakrarat Pittayawonganon[SUP] 8 [/SUP], Pilaipan Puthavathana[SUP] 5 [/SUP], William W Davis[SUP] 9 [/SUP], Joshua A Mott[SUP] 10 [/SUP], Sonja J Olsen[SUP] 10 [/SUP], Jayanton Patumanond[SUP] 11 [/SUP]
Affiliations
Background: Domestic influenza vaccine production facilitates a sustainable supply for mitigating seasonal influenza and improves national health security by providing infrastructure and experience for pandemic vaccine production, if needed.
Methods: A Phase III, double blind, randomized controlled trial was conducted from Sep 2019-Oct 2020 in healthy adults 18-64 years in Nakhon Phanom, Thailand. Randomization (3:3:1) compared study vaccine (Tri Fluvac), saline placebo, and an active comparator (licensed vaccine). Primary outcomes were superior efficacy compared to placebo based on RT-PCR-confirmed influenza virus infection within 12 months and non-inferiority compared to active comparator based on immunogenicity (HAI assay) at 28 days. Safety was also assessed.
Results: The trial enrolled 4,284 participants (Tri Fluvac = 1,836; placebo = 1,836; active comparator = 612). There were 29 RT-PCR positive influenza infections (10 Tri Fluvac, 5.5/1,000 PY; 19 placebo, 10.4/1,000PY; 0 comparator) for an absolute protective efficacy of 46.4 (95 % CI = -22.0-76.5) compared with placebo, but the power was 43.7 %. Seroconversion difference rates between Tri Fluvac and comparator at Day 28 were 1.74 (95 % CI: -2.77, 6.25), 2.22 (-2.40, 6.84), and -0.57 (-5.41, 4.27) for A(H1N1), A(H3N2), and B strains, respectively. Adverse and severe adverse events occurred in 175 (9.5 %) Tri Fluvac, 177 (10.8 %) placebo, and 66 (10.8 %) comparator arms (p-value = 0.437, Tri Fluvac vs. comparator) CONCLUSIONS: Tri Fluvac was well tolerated, and immunogenicity was non-inferior to the active comparator, meeting U.S. Food and Drug Administration (FDA) criteria for adult vaccine licensure. Few acute respiratory infections were reported during intense COVID-19 pandemic restrictions, resulting in insufficient power to evaluate clinical efficacy.
Keywords: Adult; Clinical trial; Influenza vaccines; Thailand.
. 2023 Dec 1:S0264-410X(23)01396-8.
doi: 10.1016/j.vaccine.2023.11.050. Online ahead of print. Safety and immunogenicity of locally produced trivalent inactivated influenza vaccine (Tri Fluvac) in healthy Thai adults aged 18-64 years in Nakhon Phanom: A Phase III double blinded, three-arm, randomized, controlled trial
Kriengkrai Prasert[SUP] 1 [/SUP], Prabda Praphasiri[SUP] 2 [/SUP], Hatairat Lerdsamran[SUP] 3 [/SUP], Sutthichai Nakphook[SUP] 4 [/SUP], Darunee Ditsungnoen[SUP] 5 [/SUP], Sutthinan Chawalchitiporn[SUP] 6 [/SUP], Kanlaya Sornwong[SUP] 6 [/SUP], Kittisak Poopipatpol[SUP] 7 [/SUP], Ponthip Wirachwong[SUP] 7 [/SUP], Piengthong Narakorn[SUP] 7 [/SUP], Somchaiya Surichan[SUP] 7 [/SUP], Nava Suthepakul[SUP] 7 [/SUP], Napawan Thangsupanimitchai[SUP] 7 [/SUP], Chakrarat Pittayawonganon[SUP] 8 [/SUP], Pilaipan Puthavathana[SUP] 5 [/SUP], William W Davis[SUP] 9 [/SUP], Joshua A Mott[SUP] 10 [/SUP], Sonja J Olsen[SUP] 10 [/SUP], Jayanton Patumanond[SUP] 11 [/SUP]
Affiliations
- PMID: 38042698
- DOI: 10.1016/j.vaccine.2023.11.050
Background: Domestic influenza vaccine production facilitates a sustainable supply for mitigating seasonal influenza and improves national health security by providing infrastructure and experience for pandemic vaccine production, if needed.
Methods: A Phase III, double blind, randomized controlled trial was conducted from Sep 2019-Oct 2020 in healthy adults 18-64 years in Nakhon Phanom, Thailand. Randomization (3:3:1) compared study vaccine (Tri Fluvac), saline placebo, and an active comparator (licensed vaccine). Primary outcomes were superior efficacy compared to placebo based on RT-PCR-confirmed influenza virus infection within 12 months and non-inferiority compared to active comparator based on immunogenicity (HAI assay) at 28 days. Safety was also assessed.
Results: The trial enrolled 4,284 participants (Tri Fluvac = 1,836; placebo = 1,836; active comparator = 612). There were 29 RT-PCR positive influenza infections (10 Tri Fluvac, 5.5/1,000 PY; 19 placebo, 10.4/1,000PY; 0 comparator) for an absolute protective efficacy of 46.4 (95 % CI = -22.0-76.5) compared with placebo, but the power was 43.7 %. Seroconversion difference rates between Tri Fluvac and comparator at Day 28 were 1.74 (95 % CI: -2.77, 6.25), 2.22 (-2.40, 6.84), and -0.57 (-5.41, 4.27) for A(H1N1), A(H3N2), and B strains, respectively. Adverse and severe adverse events occurred in 175 (9.5 %) Tri Fluvac, 177 (10.8 %) placebo, and 66 (10.8 %) comparator arms (p-value = 0.437, Tri Fluvac vs. comparator) CONCLUSIONS: Tri Fluvac was well tolerated, and immunogenicity was non-inferior to the active comparator, meeting U.S. Food and Drug Administration (FDA) criteria for adult vaccine licensure. Few acute respiratory infections were reported during intense COVID-19 pandemic restrictions, resulting in insufficient power to evaluate clinical efficacy.
Keywords: Adult; Clinical trial; Influenza vaccines; Thailand.