>>SOUTH SAN FRANCISCO, Calif., March 15 /PRNewswire-FirstCall/ -- Pain Therapeutics, Inc. (Nasdaq: PTIE - news), a medical research company, today presented new data on its two novel opioid painkillers, OxyTrex(TM) and MorViva(TM), at the 21st Annual Scientific Meeting of the American Pain Society in Baltimore, Maryland.
``The Company's new data present an intriguing challenge to the conventional view that opioid therapy is necessarily tied to drug dependence and tolerance,'' said Grant Schoenhard, Ph.D., Pain Therapeutics' chief scientific officer. ``In conjunction with our academic collaborators, today we presented comprehensive animal data showing that chronic doses of oxycodone and morphine need not necessarily be associated with opioid tolerance, dependence or withdrawal.''
The Company presented two technical posters today at The American Pain Society meeting:
"OxyTrex(TM), a Novel Formulation of Oxycodone, Shows Absence of
Tolerance, Physical Dependence and Naloxone-Precipitated Withdrawal
Effects in Mice," and
"MorViva(TM) Reverses and Prevents Morphine-Induced Tolerance and
Naloxone-Precipitated Withdrawal In Mice Chronically Treated with
Morphine."
Study Abstracts
Oxycodone is a widely used opioid painkiller chemically related to morphine. With repeat use, the development of tolerance and physical dependence is an often-observed feature of all opioid drugs. Pain Therapeutics is developing an alternative drug to oxycodone called OxyTrex(TM), and an alternative drug to morphine called MorViva(TM). The Company believes these two proprietary drugs offer minimal opioid tolerance and physical dependence following chronic administration. Investigators recently conducted two pre-clinical experiments to test this hypothesis.
In the first experiment, two groups of healthy mice were given chronic doses of either morphine or MorViva(TM) over ten days. As expected, mice that received morphine quickly became tolerant to the drug and no longer responded to a standard assay of analgesia by day three. Mice that received MorViva(TM), however, did not show drug tolerance; these mice showed a continuous analgesic response during the entire seven day study (p<0.01). Furthermore, when morphine tolerant mice were switched over to MorViva(TM), these mice showed an analgesic response without subsequent redevelopment of tolerance (p<0.01). These results demonstrate the ability of MorViva(TM) to prevent and to reverse opioid tolerance in laboratory animals after chronic treatment.
In the second experiment, two groups of healthy mice were given chronic doses of either oxycodone or OxyTrex(TM) over seven days. Mice that received oxycodone quickly developed drug tolerance. In contrast, mice that received OxyTrex(TM) showed an absence of opioid tolerance. In addition, OxyTrex(TM) was more potent than oxycodone over the entire duration of the study.
At the end each study mice were given naloxone to reverse the effects of both oxycodone and morphine. Mice that had been receiving oxycodone or morphine went into a classic opioid withdrawal behavior, indicating the presence of physical dependence. Mice that had been receiving OxyTrex(TM) or MorViva(TM) did not do so, indicating the absence of physical dependence (p<0.01).
The results of these pre-clinical experiments indicate the Company's OxyTrex(TM) and MorViva(TM) drugs:
Do not result in analgesic tolerance (p<0.01)
Are more potent than oxycodone and morphine, respectively (p<0.01)
Remain efficacious longer than oxycodone and morphine, respectively
(p<0.01)
Prevent withdrawal behavior, indicating the lack of physical dependence (p<0.01)
The Company's scientific posters will be available on its website, www.paintrials.com.
About Opioid Painkillers
Opioid (``narcotic'') painkillers are drugs derived from opium and the poppy plant. The clinical use of opioid drugs to treat severe pain is widely accepted throughout the world. In the United States, opioid drugs exceed $3 billion in annual sales and account for over five percent of all prescription drug sales. Despite widespread use, opioid painkillers have debilitating effects that limit their usefulness at all doses. Chronic use may lead to tolerance, dependence, abuse, or, more rarely, addiction. As a result, some patients prefer to suffer through pain rather than endure the ill effects of opioid drugs. The under-treatment of pain is a serious and growing problem in the U.S. For example, according to the National Institutes of Health, over 40 million Americans are unable to find relief from their pain.<<
Although safety data is good, pain is not a life threatening condition; thus I wouldn't expect the FDA to be overly or underly (vocabulary police are hammering my door with a battering ram) critical. OTOH, the p numbers imply a slight lack of certainty (another zero after the decimal would be nice, but perhaps this is as good as it gets for behavioral data?), and the stock is off about 5% as I type.
Cheers, Tuck |
