Freeze-dried live attenuated smallpox vaccine prepared in cell culture "LC16-KAKETSUKEN": Post-marketing surveillance study on safety and efficacy compliant with Good Clinical Practice.

Abstract

BACKGROUND:

In Japan, production of smallpox vaccine LC16m8 (named LC16-KAKETSUKEN) was restarted and was determined to be maintained as a national stockpile in March 2002.

OBJECTIVE:

To conduct a post-marketing surveillance study of the vaccination of freeze-dried live attenuated smallpox vaccine prepared in cell culture LC16-KAKETSUKEN using attenuated vaccinia strain LC16m8. The study complied with Good Clinical Practice, focusing on a comparison between primary vaccinees and re-vaccinees.

METHOD:

268 personnel (261 males and 7 females) of the Japan Ground Self-Defense Force were inoculated with LC16-KAKETSUKEN and thereafter adverse events and efficacy were evaluated.

RESULTS:

Among 268 vaccinee participants, the following vaccinees showed adverse events, none serious: 53 of 196 primary vaccinees (without previous smallpox vaccination), 4 of 71 re-vaccinees (with previous smallpox vaccination) and 1 vaccinee with unknown previous vaccination history. A breakdown of adverse events observed in this study (total 268 vaccinees) showed the following minor or mild adverse events: 52 (19.4%) swelling of axillary lymph node, 4 (1.5%) fever, 2 (0.7%) fatigue, 1 (0.4%) of rash, 14 (5.2%) erythema at the inoculation site, 1 (0.4%) swelling at the inoculation site and 1 (0.4%) autoinoculation. The incidence of adverse events for primary vaccinees (53/196; 27.0%) was significantly higher than for re-vaccinees (4/71; 5.6%). However, the proportion of vaccine take was significantly higher for primary vaccinees (185/196; 94.4%) than for re-vaccinees (58/71; 81.7%). Although the proportion of vaccine take of re-vaccinees was significantly lower than for primary vaccinees due to preexisting immunity by previous vaccination, no significant difference was found in neutralizing antibody titers between primary vaccinees and re-vaccinees at 1, 4 and 7 months after LC16-KAKETSUKEN vaccination.

CONCLUSION:

The present post-marketing surveillance study compliant with Good Clinical Practice demonstrated the efficacy and safety of the smallpox vaccine LC16-KAKETSUKEN in an adult population. LC16-KAKETSUKEN is the sole currently available licensed smallpox vaccine for both adult and pediatric populations.

• Authors: Yasumasa Nishiyama, Tatsuya Fujii, Yasuhiro Kanatani, Yasuhiko Shinmura, Hiroyuki Yokote, So Hashizume
• Journal: Vaccine (Vaccine) Vol. 33 Issue 45 Pg. 6120-7 (Nov 09 2015) ISSN: 1873-2518 [Electronic] Netherlands
• PMID: 26455406 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Chemical References

• Antibodies, Neutralizing
• Antibodies, Viral
• Smallpox Vaccine
• Vaccines, Attenuated
• smallpox vaccine LC16m8

Topics

• Adult
• Adverse Drug Reaction Reporting Systems
• Antibodies, Neutralizing (blood)
• Antibodies, Viral (blood)
• Cell Culture Techniques
• Female
• Freeze Drying
• Humans
• Immunization Programs
• Immunization, Secondary
• Japan
• Male
• Middle Aged
• Product Surveillance, Postmarketing
• Smallpox (prevention & control)
• Smallpox Vaccine (administration & dosage, adverse effects, immunology, standards)
• Vaccination
• Vaccines, Attenuated (administration & dosage, adverse effects, immunology)
• Vaccinia virus (immunology)
• Young Adult