Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT02250664 |
Other study ID # |
P50DA036114:P2S2 |
Secondary ID |
P50DA036114 |
Status |
Completed |
Phase |
Phase 1/Phase 2
|
First received |
|
Last updated |
|
Start date |
October 2016 |
Est. completion date |
October 2019 |
Study information
Verified date |
October 2022 |
Source |
University of Vermont |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
This study will examine extended exposure to cigarettes varying in nicotine content among
adults with opioid use disorder. Those with opioid use disorder are at increased risk for
smoking, nicotine dependence, and using high nicotine yield cigarettes and are also at
significantly increased risk for smoking-related adverse health consequences, including site
specific cancers, heart disease, and premature death. Studies testing an innovative
regulatory strategy of reducing the nicotine content of cigarettes to a non-addictive level
have shown promising beneficial effects (decreased smoking rate, reduced toxicant exposure,
and increased cessation) in the general population of smokers. However, these studies have
uniformly excluded vulnerable populations like those with opioid use disorder who may respond
differently considering their greater vulnerability to smoking and nicotine dependence. Thus,
little is known scientifically about how this highly vulnerable subgroup of smokers might
respond to a nicotine reduction policy. This project is designed to address that substantial
knowledge gap. This same study was also conducted in two additional vulnerable populations
under a similar protocol.
Description:
The primary overall objective of these studies is to evaluate the effects of extended
exposure to cigarettes differing in nicotine content in adults with opioid use disorder using
a 3-condition, parallel groups design. After a baseline period in which daily smoking rate
and other baseline assessments are completed, participants will be randomly assigned to one
of three cigarette conditions (nicotine content: 0.04, 2.4, and 15.8 mg nicotine/gram of
tobacco) for the 12-week experimental period.
The cigarettes to be used in this study were made under an NIH contract with production being
overseen by the Research Triangle Institute (referred to as "Spectrum cigarettes"). NIH
currently has approximately 10 million of these cigarettes (of varying types) for research
purposes. The cigarettes selected for the study span the range of yields likely to produce
the hypothesized effects, as described above. The Spectrum cigarettes are not currently
commercially available, although they are similar in many ways to marketed cigarettes (e.g.,
similar manufacturing, filter, paper, etc.).
The primary overall objective of this study is to evaluate the effects of extended exposure
to cigarettes differing in nicotine content in male and female adults with opioid use
disorder using a 3-condition, parallel groups design. After a baseline period in which daily
smoking rate and other baseline assessments are completed, participants will be randomly
assigned to one of three cigarette conditions (nicotine content: 0.04 mg, 2.4 mg, and 15.8 mg
nicotine/g of tobacco) for the 12-week experimental period.
Participants will be seen weekly throughout the 12-week experimental period to obtain
research cigarettes. Cigarettes smoked per day will be obtained by participants completing
daily Interactive Voice Response (IVR) reports of cigarettes in past 24 hours. This daily
data will be used to calculate weekly means, with week-12 means serving as the primary
outcome.
This same study was conducted in two additional vulnerable populations under a similar
protocol, with differences between protocols consisting of data collection specific to that
vulnerable population. This included information such as additional assessments of anxiety
and depression for individuals with affective disorders or other measures specific to
disadvantaged women of reproductive age. In order to explore potential differences across
individuals with different vulnerabilities, data from all three studies were combined for
analysis. A vulnerable population-by-condition or population-by-condition-by-time interaction
term was included in all analyses. In the event that these interaction terms were
statistically significant, all pairwise comparisons were conducted using a Bonferroni
multiple comparison adjustment.