Recently Completed Projects.
Nicotine Vaccine as an Aid to Smoking Cessation
The Center recently completed a phase 3, multi-center, randomized, double-blind, placebo-controlled study to assess the efficacy, immunogenicity and safety of NicVAX®, an investigational vaccine being tested to treat nicotine addiction and prevent smoking relapse. Tobacco use is a significant health burden within the United States and worldwide. New agents to help smokers achieve smoking cessation and avoid relapse are needed. NicVAX® is a nicotine conjugate vaccine meant to stimulate a specific antibody response that binds nicotine to prevent it from crossing the blood-brain barrier and interacting with the central nervous system. Results from five phase 1-2 trials have demonstrated efficacy in support of long-term smoking abstinence. If the Phase 3 studies show statistically significant results in helping treat nicotine addiction it will be a novelty breakthrough as a smoking cessation treatment that could provide assistance to millions of people who need help quitting smoking.
The Center successfully enrolled and randomized 54 participants for this phase 3 study. During the one year duration of the study, participants were provided with brief one-on-one behavioral counseling sessions as well as given a series of NicVAX®/placebo injections over a specified timeframe. Upon completion of the study, participants were invited to enroll in a follow-up study to continue to research the safety of NicVAX and analyze how many antibodies are still present in the blood stream 18 and 24 months after participants' first injections.
This study was funded by Nabi Biopharmaceuticals.
Women's Health Research Study
Smokers are significantly more susceptible to bacterial infections than are non-smokers, but few studies have actually evaluated the relationship between smoking and reproductive tract infections such as bacterial vaginosis (BV).
Bacterial vaginosis is a gynecologic condition in reproductive age women and is associated with a marked increased risk to the acquisition of sexually transmitted infections and the human immunodeficiency virus (HIV), the development of chorioaminionitis, preterm delivery, postpartum endometritis, and pelvic inflammatory disease. In observational epidemiologic studies, cigarette smoking has been a strong dose-dependent risk factor for the diagnosis of BV. It is hypothesized that smoking leads to an accumulation of vaginal amines and that the antiestrogenic effect of smoking predisposes an otherwise healthy woman to BV.
In response to the lack of information regarding the link between smoking and BV, the Center recently conducted a pilot study to investigate the relationship between smoking and the vaginal microbial communities as well as the effects of smoking cessation on the vaginal microbiome. Secondary aims focused on the outcome of smoking on the oral and nasal microbiome. The study was divided into two parts, Phase I (cross-sectional), which evaluated the microbiome between female smokers and non-smokers, and Phase II, which evaluated the effects of smoking cessation on the vaginal microbiome. In Phase I, twenty smokers and twenty non-smokers were recruited and asked to collect one oral sample and one nasal sample. Participants also self-collected two samples from the mid-vagina and measured the vaginal pH using a disposable pH glove. The samples were used to characterize the microbial communities in smokers versus non-smokers. The participants in Phase II included nine smokers, who over the course of twelve weeks, self-administered a daily course of an over-the-counter nicotine patch, NicoDerm® CQ®, self-collected daily vaginal samples, and completed a daily diary on activities and events such as sexual behavior and menstrual cycle. Participants also participated in weekly behavioral counseling sessions to help them quit smoking. This data collection ultimately helped us to evaluate the effects of smoking cessation on the vaginal microbiome and add to the knowledge of smoking and reproductive health.
This study was funded by the University of Maryland, College Park and done in collaboration with Rebecca M., Brotman, PhD at the University of Maryland, Baltimore. All data collection took place in College Park and de-identified samples were sent to Baltimore for analysis.
Physiologic Impact of New Smokeless, Spitless Tobacco Products
Smokeless, spitlees, tobacco products (SST), also called "snus", the Swedish word for snuff, is gaining a foot-hold in the US. With the rate of smoking falling, and use of smokeless tobacco increasing, all major cigarette manufacturers world-wide have entered the smokeless market, often using their popular brand names (e.g., Marlboro Snus, Camel Snus). Newly introduced are smokeless, spitless products with high levels of candy flavorings, certain to appeal to adolescents.
We have developed a system for rapid testing of toxicity and abuse potential of these new products. The system will be helpful when FDA is granted regulatory authority over tobacco.
We recently completed a randomized, single-blind, cross-over trial of two SST products to determine if variation in the proportion of free-base nicotine in new SST products influences perceptions of the sensory and hedonistic qualities of the products, plasma nicotine boost, cardiovascular reactivity, and/or speed of nicotine delivery to the brain (using electroencephalogram- EEG).
We completed a study evaluating Selegiline Transdermal System (STS), as an aid to help people quit smoking. Selegiline has previously been approved by the FDA to treat depression and Parkinson Disease symptoms, but not as a smoking cessation aid. Participants were provided with smoking cessation counseling, regardless of their medication assignment. Full study participation lasted approximately 6 months. The study was sponsored by the National Institute on Drug Abuse (NIDA) and the US Department of Veterans Affairs.