SANTA MONICA, Calif., Oct. 06, 2022 (GLOBE NEWSWIRE) -- Opiant Pharmaceuticals, Inc. (Opiant) (NASDAQ: OPNT), a specialty pharmaceutical company developing medicines to treat addictions and drug overdose, today announced that the last patient has been enrolled in the Phase 2 clinical trial of OPNT002, nasal naltrexone, for patients with Alcohol Use Disorder (AUD). The total trial duration per patient is 20 weeks, with the last patient enrolled expected to complete the study in early 2023 and with top line data anticipated to follow mid-year.

"We are pleased to have completed patient enrollment ahead of schedule and are looking forward to concluding the treatment phase of this study and releasing top-line data next year,” said Roger Crystal, M.D., President and Chief Executive Officer of Opiant. "This study is a critical step in our effort to develop alternative therapeutic treatment options to improve the lives of people suffering from alcohol use disorder."

Opiant launched its Phase 2 clinical study of OPNT002 for the treatment of alcohol use disorder in January 2022. The multi-center, double-blind, randomized, placebo-control Phase 2 study is being conducted in Europe, and is designed to evaluate OPNT002 efficacy, safety, and tolerability in 300 patients with AUD. The trial is being conducted using a Sequential Parallel Comparison Study Design, which is useful in psychiatric studies to reduce the impact of the placebo effect on the assessment of treatment response. The primary end point will be measured by the proportion of patients showing an improvement in World Health Organization (WHO) Risk Levels of Alcohol Consumption consisting of a 2-level reduction from baseline to end of treatment. 

About OPNT002
Clinical and preclinical studies have shown that alcohol releases endorphins, which are the brain’s endogenous opioids. These endorphins are thought to activate opioid receptors, which contribute to alcohol’s reinforcing and addictive properties. Current naltrexone treatments work to block mu-opioid receptors when administered orally or through injection. However, converging lines of evidence indicate that activation of delta-opioid receptors also contributes to the reinforcing properties of alcohol. The effective blockade of delta‐opioid receptors requires much higher plasma naltrexone concentrations than is achieved by currently approved naltrexone products¹.

Opiant is developing OPNT002 to rapidly increase plasma concentrations of naltrexone following dosing and thereby block mu and delta-opioid receptors. In previous research, OPNT002 has demonstrated rapid nasal absorption, delivering high levels of naltrexone yet with a short half-life. Results from Phase 1 studies demonstrate that OPNT002 produces maximum plasma concentrations that are approximately 50% higher than orally administered naltrexone. This feature, along with a very rapid onset and a short plasma half-life, are characteristics ideally suited to developing OPNT002 for ‘as needed’ nasal dosing in anticipation of drinking, or once drinking has started^2,3. 

About Alcohol Use Disorder
Alcohol use disorder is a chronic relapsing brain disease characterized by compulsive use of alcohol and the inability to control intake. It is the third leading preventable cause of death in the United States, and according to the WHO, harmful use of alcohol is responsible for 5.1% of the global burden of disease^4,5. A report by the Centers for Disease Control and Prevention, found that deaths from alcohol use increased by 43% from 2006 to 2018⁶. Currently, less than 10% of individuals with AUD seek treatment for their drinking problems⁷, and many individuals with AUD who do not seek alcohol treatment report not wanting to stop drinking as their primary reason for not seeking treatment⁸. Individuals with AUD who do not initially accept an abstinence goal may find treatment more appealing if it is focused on reductions in drinking.

About Opiant Pharmaceuticals, Inc. 
Opiant Pharmaceuticals, Inc., the company that developed NARCAN^® Nasal Spray, is building a leading franchise of new medicines to combat addictions and drug overdose. For more information visit: www.opiant.com.

Forward-Looking Statements
This press release contains forward-looking statements, including the anticipated results of the Phase 2 study in 2023. These statements relate to future events or our future financial performance and involve known and unknown risks, uncertainties and other factors that may cause our or our industry's actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activity, performance or achievements expressed, implied or inferred by these forward-looking statements, and among other things, our ability to maintain cash balances and successfully commercialize or partner our product candidates currently under development. In some cases, you can identify forward-looking statements by terminology such as "may," "will," "should," "could," "would," "expects," "plans," "intends," "anticipates," "believes," "estimates," "predicts," "projects," "potential," or "continue" or the negative of such terms and other comparable terminology. These statements are only predictions based on our current expectations and projections about future events. You should not place undue reliance on these statements. Actual events or results may differ materially. In evaluating these statements, you should specifically consider various factors. Additional factors that could materially affect actual results can be found in our Form 10-K for the year ended December 31, 2021, and our Form 10-Q for the quarters ended March 31, 2022 and June 30, 2022, filed with the Securities and Exchange Commission on March 4, 2022, May 10, 2022 and August 10, 2022, respectively, including under the caption titled "Risk Factors."  These and other factors may cause our actual results to differ materially from any forward-looking statement. We undertake no obligation to update any of the forward-looking statements after the date of this press release to conform those statements to reflect the occurrence of unanticipated events, except as required by applicable law.

For Media and Investor Inquiries:
Ben Atkins, Opiant
(310) 598-5410
batkins@opiant.com

1.   Weerts E, Kim Y, Wand G, et al. Differences in δ and μ opioid receptor blockade measured by positron emission tomography in naltrexone-treated recently abstinent alcohol-dependent subjects. Neuropsychopharm. 2008;33:653-665. https://www.nature.com/articles/1301440

2.   Krieter P, et al. Enhanced Intranasal Absorption of Naltrexone by Dodecyl Maltopyranoside: Implications for the Treatment of Opioid Overdose. Journal of Clinical Pharmacology, 2019 https://www.opiant.com/wp-content/uploads/2019/05/2019-IN-NTX-J-Clin-Pharm-1.pdf

3.   Research & Development Meeting on Emerging Therapeutics for the Treatment of Addiction and Drug Overdose. Available at: https://ir.opiant.com/events/event-details/research-development-meeting-emerging-therapeutics-treatment-addiction-and

4. National Institute on Alcohol Abuse and Alcoholism. Available at: https://www.niaaa.nih.gov/alcohol-health/overview-alcohol-consumption/alcohol-use-disorders

5. World Health Organization. Available at: https://www.who.int/health-topics/alcohol#tab=tab_1

6.   Spencer, M et al. Rates of Alcohol-induced Deaths Among Adults Aged 25 and Over in Urban and Rural Areas: United States, 2000–2018, NCHS Data Brief No. 383, October 2020

7. Grant BF, Goldstein RB, Saha TD, Chou SP, Jung J, Zhang H, Pickering RP, Ruan WJ, Smith SM, Huang B, Hasin DS. Epidemiology of DSM-5 Alcohol Use Disorder: Results From the National Epidemiologic Survey on Alcohol and Related Conditions III. JAMA Psychiatry. 2015 Aug;72(8):757-66. doi: 10.1001/jamapsychiatry.2015.0584. PMID: 26039070; PMCID: PMC5240584.

8. Figure 25 in https://www.samhsa.gov/data/sites/default/files/NSDUH-DR-FRR3-2014/NSDUH-DR-FRR3-2014/NSDUH-DR-FRR3-2014.htm

Source: Opiant Pharmaceuticals