Sandra D. Comer, Ph.D.
Dr. Sandra Comer is a Professor of Clinical Neurobiology in the Department of Psychiatry at the College of Physicians and Surgeons of Columbia University, and a Research Scientist at the New York State Psychiatric Institute. Dr. Comer received her undergraduate degree at Vanderbilt University (1987), and completed her graduate training at the University of Michigan, where she received her Master of Science (1988) and Doctorate in Philosophy (1992) degrees for her research on the effects of opioid drugs in the laboratory of Dr. James H. Woods. Following graduate school, Dr. Comer completed a two year post-doctoral fellowship at the University of Minnesota, Minneapolis. There she received training in preclinical animal models of cocaine self-administration in rodents and non-human primates in the laboratory of Dr. Marilyn Carroll. In 1993, Dr. Comer began working at the Division on Substance Abuse at Columbia University. Here she received training in human preclinical studies under the mentorship of Dr. Marian Fischman and Dr. Richard Foltin. Dr. Comer's research focus has been on the development and testing of novel approaches to the treatment of opioid dependence, and the influence of sex differences and hormonal fluctuations on responses to pain and opioid medications.
Current Research Activities:
A primary focus of the Division on Substance Abuse is to investigate potential treatment medications for opioid dependence using a preclinical human laboratory model. The basic tenet of this model is that in order to determine the potential utility of a medication for opioid dependence, the effects of the medication on drug-taking must be studied directly. Dr. Comer has investigated the effects of selective opioid receptor antagonists (naltrexone) and partial agonists (buprenorphine) on a range of opioid effects (self-administration, subjective ratings, physiological measures). She and her colleagues have shown that a depot formulation of naltrexone produces a dose-dependent antagonism of heroin's effects for up to a month. More recently, Dr. Comer and colleagues have been investigating the effects of memantine, an antagonist at N-methyl-D-aspartate receptors, which may prove to be an effective treatment for opioid dependence by decreasing both craving for heroin and the euphoric effects produced by heroin. In addition, the effectiveness of buprenorphine and the buprenorphine/naloxone combination in reducing heroin's effects have been investigated. Another line of research has examined the conditions under which buprenorphine itself may be reinforcing. In these studies, individuals were given the opportunity to self-administer buprenorphine alone and buprenorphine in combination with naloxone. The reinforcing effects of buprenorphine were also compared to those of the full opioid agonist, methadone. These studies were all conducted in opioid dependent individuals with the aim of understanding and developing new medications for the treatment of opioid dependence.
Dr. Comer was recently awarded another grant to extend this line of research by examining the relative reinforcing effects of several different opioid agonists including oxycodone, buprenorphine, fentanyl, morphine, and heroin. The effectiveness of buprenorphine in reducing the effects of these different agonists will also be studied.
Sex Differences and Hormonal Influences on Pain Responsivity
Dr. Comer and colleagues have developed a laboratory model to investigate the responses to experimentally-induced painful stimuli in men, normally-menstruating women, and women maintained on monophasic oral contraceptives. Previous studies have demonstrated that some opioid medications may be more effective and longer lasting in females, compared to males, but this effect has yet to be fully characterized in humans. Specifically, the effects of morphine, the prototypic agonist at the mu subtype of opioid receptor, and butorphanol, a mixed action opioid with effects at the kappa subtype of opioid receptor, are being studied.
Dr. Comer was recently awarded another grant to extend this line of research by investigating the conditions under which prescription opioid medications may be abused. Self-administration of oxycodone and codeine will be compared in drug abusers and non-drug abusers under conditions of experimentally-induced pain or no pain. This research will potentially shed light on the populations of individuals who may abuse prescription opioids, and the conditions under which these medications may be abused.
Dr. Comer has mentored undergraduate and graduate students completing thesis projects, and contributes to the training of postdoctoral research fellows funded through Dr. Herbert Kleber’s Postdoctoral Fellowship.