Trial Outcomes & Findings for A Randomized Trial of Vaccine Adherence in Young Injection Drug Users (NCT NCT00244374)

NCT ID: NCT00244374

Last Updated: 2013-09-30

Results Overview

The primary outcome was the completion of the four-dose vaccine series in a 12 month period.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

546 participants

Primary outcome timeframe

12 months

Results posted on

2013-09-30

Participant Flow

Between 08/31/2004 and 11/30/2007, street-based outreach workers distributed study invitation cards to potential subjects in neighborhoods of San Francisco where young injection drug users (IDU) are known to congregate. Initial Contact form included self-reported age, IDU in last 30 days, hepatitis B immunization and HIV-positive status.

1304 persons completed initial contact form; 645 were eligible and 546 opted to participate in the cross-sectional study. The vaccine adherence cohort (n=167) included participants enrolled prior to 3/31/2007 who met additional eligibility criteria.

Participant milestones

Participant milestones
Measure
Cross-sectional/Screening
Cross-sectional screening to determine eligibility for vaccine adherence trial
AIC Only
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
Pre-Randomization Cross-sectional Study
STARTED
546
0
0
0
0
Pre-Randomization Cross-sectional Study
COMPLETED
409
0
0
0
0
Pre-Randomization Cross-sectional Study
NOT COMPLETED
137
0
0
0
0
Evaluation for Vaccine Adherence Cohort
STARTED
440
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Eligible for Vaccine Adherence Cohort
217
0
0
0
0
Evaluation for Vaccine Adherence Cohort
COMPLETED
167
0
0
0
0
Evaluation for Vaccine Adherence Cohort
NOT COMPLETED
273
0
0
0
0
Vaccine Adherence Cohort
STARTED
0
47
43
36
41
Vaccine Adherence Cohort
COMPLETED
0
47
43
36
41
Vaccine Adherence Cohort
NOT COMPLETED
0
0
0
0
0

Reasons for withdrawal

Reasons for withdrawal
Measure
Cross-sectional/Screening
Cross-sectional screening to determine eligibility for vaccine adherence trial
AIC Only
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
Pre-Randomization Cross-sectional Study
Did not complete baseline procedures
105
0
0
0
0
Pre-Randomization Cross-sectional Study
Technical difficulty loss of data
17
0
0
0
0
Pre-Randomization Cross-sectional Study
Did not respond to willingness questions
14
0
0
0
0
Pre-Randomization Cross-sectional Study
Interviewer lack confidence in responses
1
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Evidence of hepatitis B immunization
172
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Unable/unwilling to complete enrollment
51
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Did not return for screening test result
34
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Returned for results after enroll window
4
0
0
0
0
Evaluation for Vaccine Adherence Cohort
Declined to participate in cohort
12
0
0
0
0

Baseline Characteristics

A Randomized Trial of Vaccine Adherence in Young Injection Drug Users

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
All Participants
n=546 Participants
Participants in pre-randomization cross-sectional study
Age, Customized
Age 0 - 14 years
0 Participants
n=5 Participants
Age, Customized
Age 15 - 29 years
546 Participants
n=5 Participants
Age, Customized
Age >= 30 years
0 Participants
n=5 Participants
Sex/Gender, Customized
Female
149 Participants
n=5 Participants
Sex/Gender, Customized
Male
395 Participants
n=5 Participants
Sex/Gender, Customized
Unknown/Other/Not Reported
2 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
52 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
460 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
34 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
10 Participants
n=5 Participants
Race (NIH/OMB)
Asian
7 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
2 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
11 Participants
n=5 Participants
Race (NIH/OMB)
White
392 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
63 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
61 Participants
n=5 Participants
Region of Enrollment
United States
546 participants
n=5 Participants

PRIMARY outcome

Timeframe: 12 months

The primary outcome was the completion of the four-dose vaccine series in a 12 month period.

Outcome measures

Outcome measures
Measure
AIC Only
n=47 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
n=43 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
n=36 Participants
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
n=41 Participants
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
Vaccine Series Completion
Completed <4 vaccine doses
31 participants
23 participants
28 participants
31 participants
Vaccine Series Completion
Completed 4 vaccine doses
16 participants
20 participants
8 participants
10 participants

SECONDARY outcome

Timeframe: 12 months

Population: 139 participants who completed 3 vaccine doses were included in the analysis. Enrollment for this aim continued after enrollment into the 12-month vaccine adherence trial closed; an additional 51 persons were found eligible and enrolled.

To examine the effect of hepatitis C virus (HCV) infection on vaccine effectiveness, we compared anti-HBs (antibody to the hepatitis B surface antigen) seroconversion after three vaccine doses between anti-HCV (antibody to the hepatitis C virus) positive and anti-HCV negative participants.

Outcome measures

Outcome measures
Measure
AIC Only
n=31 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
n=108 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
Hepatitis B Surface Antibody Seroconversion After 3 Vaccine Doses
anti-HBs positive
20 Participants
90 Participants
Hepatitis B Surface Antibody Seroconversion After 3 Vaccine Doses
anti-HBs negative
11 Participants
18 Participants

SECONDARY outcome

Timeframe: Baseline

Population: Cross-sectional analysis of 355 subjects enrolled between 2004 and 2006

In a cross-sectional analysis of 355 subjects enrolled between 2004 and 2006, we estimate the associations between travel in the 3 months prior to baseline and behaviors occurring in the 30 days prior to baseline, such as drug and alcohol and sexual behaviors, that may facilitate the spread of viral infections.

Outcome measures

Outcome measures
Measure
AIC Only
n=221 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
n=134 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
Viral Transmission Risk Behavior Association With Travel
Used (injected/snorted/smoked) crack cocaine
56.5 percentage of participants
45.5 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Used (injected/snorted/smoked) methamphetamine
67.4 percentage of participants
78.4 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Injected daily, past 30 days
23.5 percentage of participants
33.6 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Number of injecting partners >=5
59.7 percentage of participants
41.1 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Used (injected/snorted/smoked) heroin
83.7 percentage of participants
76.1 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Used (injected/snorted/smoked) powder cocaine
55.7 percentage of participants
41.0 percentage of participants
Viral Transmission Risk Behavior Association With Travel
More than one of the above (poly-substance use)
87.2 percentage of participants
76.3 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Heavy drinking (>14, >21 per week; women, men)
52.3 percentage of participants
13.7 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Drank until blacked out
36.8 percentage of participants
13.7 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Lent a needle/syringe
53.3 percentage of participants
46.3 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Injected with someone else's used needle/syringe
52.3 percentage of participants
37.8 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Pooled money to buy drugs
86.4 percentage of participants
66.2 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Shared cooker/spoon to prepare drugs
67.0 percentage of participants
48.1 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Syringe was backloaded
62.7 percentage of participants
47.4 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Did someone's "rinse"
42.5 percentage of participants
34.3 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Median number of sexual partners >=2
58.4 percentage of participants
38.1 percentage of participants
Viral Transmission Risk Behavior Association With Travel
Traded sex for money or drugs
11.3 percentage of participants
11.9 percentage of participants
Viral Transmission Risk Behavior Association With Travel
>90% condom use if sexually active
24.3 percentage of participants
22.5 percentage of participants

SECONDARY outcome

Timeframe: Baseline

Population: Per the Participant Flow, 409 participants in the cross-sectional study had complete and valid baseline data

We assessed knowledge about vaccine trials and willingness to participate in preventive HIV vaccine trials by asking the question: "How willing would you be to join a study of a vaccine to prevent HIV infection, if the study were to start tomorrow?". Willingness was measured on a 4-point response scale, ranging from 1 (Definitely not willing) to 4 (Definitely willing).

Outcome measures

Outcome measures
Measure
AIC Only
n=409 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
HIV Vaccine Trial Willingness
4=Definitely willing
147 Participants
HIV Vaccine Trial Willingness
1=Definitely not willing
24 Participants
HIV Vaccine Trial Willingness
2=Probably not willing
68 Participants
HIV Vaccine Trial Willingness
3=Probably willing
170 Participants

SECONDARY outcome

Timeframe: Baseline

Population: Per the Participant Flow, 409 participants in the cross-sectional study had complete and valid baseline data

Participants were asked if they agreed or disagreed with or were unsure of each of eight statements about HIV vaccine trial concepts from the HIV Network for Prevention Trials (HIVNET). 1. Preventive HIV vaccine studies enroll people who are HIV-positive and HIV-negative. 2. Some participants in HIV vaccine studies will get a real vaccine, and some will get a placebo (an inactive substance). 3. Only vaccines known to be at least 50% effective at preventing HIV are tested in HIV vaccine studies. 4. Once a large scale HIV vaccine study begins, we can be sure the vaccine is completely safe. 5. Participants are told whether they got the HIV vaccine or the placebo at the end of HIV vaccine studies. 6. HIV vaccines will never affect a person's HIV test results. 7. An HIV vaccine can infect a person with HIV disease. 8. People in vaccine studies know whether or not they got the placebo because only the vaccines cause side effects.

Outcome measures

Outcome measures
Measure
AIC Only
n=409 Participants
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC), for administration of viral hepatitis immunizations at Month 1, 2, 6.
AIC + Outreach
Subjects randomized to a public health department clinic, the Adult Immunization Clinic (AIC)) for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
SEP Only
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6.
SEP + Outreach
Subjects randomized to a set of syringe exchange programs for administration of viral hepatitis immunizations at Month 1, 2, 6, plus outreach worker adherence support to receive all immunizations
HIV Vaccine Trial Knowledge
5-8 Correct answers
94 Participants
HIV Vaccine Trial Knowledge
0-4 Correct answers
315 Participants

Adverse Events

AIC Only

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

AIC + Outreach

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

SEP Only

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

SEP + Outreach

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Dr. Paula J. Lum

University of California, San Francisco

Phone: 415-476-4082

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place