Author(s):
Dhanashree P. Sanap, Anil Kumar Dindigala
Email(s):
dhanashree.sanap@bvcop.in
DOI:
10.52711/0974-360X.2026.00553 
Address:
Dhanashree P. Sanap1*, Anil Kumar Dindigala2
1Bharati Vidyapeeth’s College of Pharmacy, Sector-8, CBD Belapur, Navi Mumbai 400614, Maharashtra, India.
2Scientist, Thermo Fisher Scientific, Greenville, NC, USA.
*Corresponding Author
Published In:
Volume - 19,
Issue - 8,
Year - 2026
ABSTRACT:
Naltrexone, an opioid antagonist, works by blocking opioid receptor sites and effectively reducing alcohol intake. It has no potential for abuse and only mild adverse effects, making it a suitable pharmacological treatment for opioid dependence. However, due to extensive hepatic first-pass metabolism, oral naltrexone often faces poor patient adherence. Naltrexone is primarily prescribed for alcohol dependence and is typically used alongside psychosocial interventions; therefore, extended-release formulations are essential to improve treatment outcomes. Various extended-release forms of naltrexone—including microspheres, implants, injectable depots, and enzyme-activated devices—have been developed by researchers using diverse formulation approaches. These delivery systems have demonstrated the ability to sustain naltrexone release for at least one month with minimal initial burst. Scientists have employed specific formulation techniques, combining biodegradable polymers to achieve controlled drug release with reduced initial burst effects. Approaches such as polymerization, microgel technology, and thermosensitive hydrogels have successfully prolonged naltrexone release up to 60 days. In vitro evaluation methods for naltrexone microspheres have been established, with USP apparatus 4 enabling a linear correlation between accelerated and real-time release profiles. Additionally, in vitro–in vivo correlations (IVIVCs) based on compendial dissolution apparatus have been developed to monitor manufacturing variations and predict in vivo performance. Clinical trials assessing extended-release naltrexone have been conducted across diverse populations including prisoners, alcohol and opioid-dependent individuals, and HIV patients, confirming the safety and effectiveness of these formulations. Despite promising results, many extended-release naltrexone products have not yet received widespread clinical approval, highlighting the need for larger, long-term studies. There remains significant potential for further research to optimize scalable production processes and enhance manufacturing yields for these complex injectable formulations.
Cite this article:
Dhanashree P. Sanap, Anil Kumar Dindigala. Formulation Development Strategies, In vivo In vitro Study and Clinical Trials Prospective of Naltrexone Extended-Release Formulations: A Structured Review. Research Journal of Pharmacy and Technology. 2026;19(8):3939-8. doi: 10.52711/0974-360X.2026.00553
Cite(Electronic):
Dhanashree P. Sanap, Anil Kumar Dindigala. Formulation Development Strategies, In vivo In vitro Study and Clinical Trials Prospective of Naltrexone Extended-Release Formulations: A Structured Review. Research Journal of Pharmacy and Technology. 2026;19(8):3939-8. doi: 10.52711/0974-360X.2026.00553 Available on: https://www.rjptonline.org/AbstractView.aspx?PID=2026-19-8-70
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