Potential Therapeutic Transdermal Psychoactive Drug Delivery Technology

Abstract

There is a high rise in depression sufferers worldwide, which has necessitated the need for diverse drug delivery systems that would include conventional and emerging transdermal delivery strategies. A number of approaches have been investigated, including a pro-drug approach, formulation of transdermal patches, micro emulsification, and chemical and physical enhancing technologies.

Important Compound Classes

Titles

Transdermal Psychoactive Alkaloid Composition and Preparation Thereof; and Transmucosal Psychoactive Alkaloid Composition and Preparation Thereof

Patent Publication Numbers

WO 2022/140842 A1 (URL:https://patents.google.com/patent/WO2022140842A1/en?oq=WO+2022%2f140842+A1)

WO 2022/140841 A1 (URL: https://patents.google.com/patent/WO2022140841A1/en?oq=WO+2022%2f140841+A1)

Publication Dates

July 7, 2022 and July 7, 2022

Priority Applications

US63/139,453 and CA3123774 (WO 2022/140842 A1); and CA3113240 (WO 2022/140841 A1)

Priority Dates

January 20, 2021 and July 1, 2021 (WO 2022/140842 A1); and March 24, 2021 (WO 2022/140841 A1)

Inventors

Moss, R.; Lightburn, B.; Ranken, L.

Assignee Company

Psilo Scientific Ltd [CA/CA], 4506 Bellevue Dr., Vancouver, British Columbia V6R IE3, Canada

Disease Area

Alcohol use disorder, addiction and pain

Biological Target

Serotonin receptor

Summary

Transdermal drug delivery (TDD) systems deliver biologically active agents via the skin portals for localized or systemic effects, and are considered non-invasive methods that can be self-administered. However, there are requirements for a drug to be suitable for TDD, including a maximum molecular weight of 1000 Da, a balance between hydrophobicity and hydrophilicity, and a polarity that allows penetration of the stratum corneum skin barrier. Over the past few decades, various strategies involving chemical and physical methods have been developed to improve transdermal drug permeation, including penetration enhancers, laser, electroporation, sonophoresis, microjet, and iontophoresis. However, some of these techniques are usually expensive and cumbersome to use, and still exhibit limited efficiency toward a successful transdermal delivery, especially for macromolecules.

Most protein and peptide drugs are hydrophilic and macromolecular in nature, and therefore they cannot easily penetrate into the skin. Since their inception, TDDs have significantly influenced the delivery of various therapeutic agents, especially in hormonal therapy, pain management, and treatment of diseases of the cardiovascular and central nervous systems. For instance, a transdermal patch carries medicated adhesive that is placed on the derma and delivers a specific dose through the skin into systemic circulation, which provides a controlled release of the medication. TDDs circumvent the hepatic first-pass metabolism and gastrointestinal side effects, they are administered less frequently, they enable the use of drugs with a short biological half-life, and they enhance patient compliance. TDDs can be easy to administer, painless, and non-invasive when compared to other types of delivery systems such as oral, intravenous, topical, and intramuscular.

Figure 1 shows the multiple layers of the skin, which can be divided into the epidermis, which has the protective function, and the dermis, where blood vessels are located and which produces skin cells. Each layer of the skin has elements that interfere with transdermal delivery.

Figure 1.

Schematic illustration of protein and peptide drug delivery by conventional injections and microneedles. [Reprinted with permission from Elsevier: Acta Pharmaceutica Sinica B, 2022, DOI: 10.1016/j.apsb.2021.03.003].

The multi-layered structure of the skin enhances the protection of the body by blocking environmental hazards such as heat, chemicals, and toxins. Consequently, the skin’s defense mechanism can be an impediment to TDDs. Some of the limitations to TDDs are that some patients may develop dermatitis or allergic reactions, they work well for drugs with molecular weight that is less than 500 Da, and a log P between 1 and 3 is preferable. TDDs could be problematic when there is person-to-person skin variability due to aging. In addition, hydrophilic drugs are not suitable, as they permeate the skin too slowly and may not deliver the required therapeutic dose.

This Patent Highlight showcases transdermal and transmucosal psychoactive alkaloids that are extracted or synthesized. Some of the psychoactive compounds have shown therapeutic values and are being prescribed by physicians and other healthcare practitioners for various conditions, including alcohol use disorders, depression, pain, analgesic, opioid addiction, and so forth.

Key Structures

Biological Data

The table shows psychoactive component purified extracts containing psychoactive alkaloid concentrations of 30% by weight.

The author declares no competing financial interest.