NLS Pharmaceutics to Present New Data on the Dual Efficacy of Mazindol ER in Fentanyl Reward and Withdrawal at the 2025 ASCP Annual Meeting
Rhea-AI Summary
NLS Pharmaceutics (NASDAQ: NLSP) will present new preclinical data on Mazindol ER at the 2025 ASCP Annual Meeting in Scottsdale, Arizona. The study (KO-943) demonstrates Mazindol's dual efficacy in reducing both fentanyl reward effects and withdrawal symptoms in rodent models.
Key findings show that Mazindol at 0.5 mg/kg significantly reduced fentanyl-induced conditioned place preference in mice, while doses of 0.5 and 1.0 mg/kg decreased withdrawal symptoms in rats. The drug's multiple-target profile, including partial mu-opioid receptor agonist, 5-HT1A receptor agonist, and orexin-2 receptor modulation, suggests potential as a novel non-opioid therapeutic for opioid addiction.
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The preclinical study to be featured in the poster was conducted by Key-Obs SAS in collaboration with NLS and other European academic institutions. The study results demonstrate that Mazindol significantly reduced both the rewarding effects of fentanyl and the severity of its withdrawal symptoms in validated rodent models.
Highlights from Study KO-943:
- Experiment 1 (Reward/CPP Model): In C57BL/6J mice, Mazindol at 0.5 mg/kg significantly reduced fentanyl-induced conditioned place preference ("CPP"), effectively neutralizing the behavioral reward effects typically observed with fentanyl exposure.
- Experiment 2 (Withdrawal Model): In Sprague-Dawley rats, Mazindol administered at 0.5 and 1.0 mg/kg dose-dependently reduced fentanyl withdrawal symptoms, including agitation, salivation, and motor disturbances, as measured by the Gellert-Holtzman scale.
Expert Commentary
"The study results show that Mazindol produced robust effects on both reward and withdrawal symptoms, demonstrating its potential as a non-opioid therapeutic candidate option for fentanyl dependence," said Dr. Jean-Charles Bizot, Director of Research at Key-Obs SAS and lead investigator of Study KO-943. "The data support further exploration in clinical models, particularly given the multi-receptor activity of Mazindol."
"These data suggest the potential of a multiple-target profile for Mazindol to address opioid addiction through a novel mechanism of action. By targeting partial mu-opioid as receptor agonist, strong 5-HT1A receptor agonist activity, and orexin-2 receptor modulation, Mazindol may offer a unique, multi-modal strategy to reduce opioid reward and withdrawal symptoms, showing its potential as a non-opioid therapeutic. These findings are supported by results from both reward and withdrawal animal models, including the CPP paradigm in C57BL/6J mice and naloxone-precipitated withdrawal in Sprague-Dawley rats. Clinical trials, including the planned NLS-6002 study, are needed to validate these results in humans," said Dr. Eric Konofal, MD, PhD, Chief Scientific Officer of NLS Pharmaceutics.
Broader Implications for ADHD and CNS Disorders
While standard stimulant and non-stimulant medications approved for ADHD have shown no significant efficacy in addressing opioid withdrawal or reward, Mazindol's ability to reduce both in fentanyl-exposed animals suggests it may offer advantages over conventional treatments. This aligns with clinical observations that differentiate the pharmacodynamic profile of Mazindol from traditional monoaminergic agents, as discussed in comparative studies such as Wigal et al., CNS Drugs (2018).
About ASCP
The ASCP Annual Meeting is one of the world's premier scientific events for advancing neuropsychopharmacology and psychiatry. It brings together leading clinicians, researchers, and innovators to present and discuss the latest advances in CNS therapeutics.
About NLS Pharmaceutics Ltd.
NLS Pharmaceutics Ltd. is a Swiss-based clinical-stage biopharmaceutical company developing innovative therapies for rare and complex CNS disorders. The company's pipeline includes drug candidates for ADHD, narcolepsy, hypersomnia, and substance use disorders, with a focus on repurposed and reformulated compounds.
For more information, visit www.nlspharma.com
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SOURCE NLS Pharmaceutics Ltd.