Study of Reactogenicity, Safety, Immunogenicity, and Pock Lesion Formation of a Cell-Cultured Smallpox Vaccine Compared to Dryvax®

A Phase 1 Study of Reactogenicity, Safety, Immunogenicity, and Pock Lesion Formation (Take Rate) of a Cell-Cultured Smallpox Vaccine (CCSV) Compared to a Calf Lymph Vaccine (Dryvax®)

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00042094

Enrollment

350

Registered

2002-07-26

Start date

2002-03-31

Completion date

2003-03-31

Last updated

2011-06-30

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Smallpox

Keywords

Smallpox, Smallpox Vaccine, Vaccinia

Brief summary

This study will evaluate the safety and efficacy of both Dryvax® and the new cell-cultured vaccine (CCSV) in a comparative fashion. Across 3 cohorts, 150 vaccinia-naive volunteers will be randomly assigned to receive either CCSV (100 volunteers) or Dryvax® (50 volunteers) in a blinded fashion. Subjects will be followed closely for up to 6 months and a subgroup of volunteers will be followed up to 3 years in order to evaluate the duration of immunity following vaccination. Another cohort will enroll 100 vaccinia-experienced volunteers and randomly assign them to receive either CCSV (50 volunteers) or Dryvax® (50 volunteers) and a sub group will be followed up to 3 years. A fifth cohort will enroll 100 vaccinia-naive volunteers and randomly assign them to receive different dilutions of CCSV (1:1, 1:5, 1:25, and 1:50).

Interventions

BIOLOGICALCell-Cultured Smallpox Vaccine compared to Dryvax®

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

PREVENTION

Masking

DOUBLE

Eligibility

Sex/Gender

ALL

Age

18 Years to 65 Years

Healthy volunteers

Yes

Inclusion criteria

* Have never received smallpox vaccine or previously received an experimental smallpox vectored vaccine (for vaccinia-naive cohorts only) * Have been previously vaccinated within the last 10 years (vaccinia-experienced cohort only) * Must agree to have blood samples banked for future research testing * Have not participated in any clinical trial using investigational product within past month * No current or past history of exfoliative skin problems * Not have regular contact with children under 3 years of age until scab at site of vaccination has fallen off (around 21 days or 3 weeks after vaccination) * Do not have a positive test for HIV virus, hepatitis C virus, or hepatitis B surface antigen * Are not a health care worker caring for newborns, patients that are immunocompromised or have skin that is adversely altered * Will not engage in direct patient care until immunization scab falls off (around 21 days or 3 weeks after vaccination) if health care worker

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026