Microneedles are tiny self-administered patches that offer a convenient and painless way to deliver medicines across the skin barrier. They outperform oral methods in terms of bioavailability and can potentially replace hypodermic needles in many applications. Thermostable microneedles do not rely on costly and complex cold chains, which can improve global access to essential medications. This article examines advances in microneedle technology, disease treatment, and how microneedles can improve patient compliance and health care outcomes.
A Painless Dissolving Microneedle Patch Solves Multiple Challenges
A painless dissolving microneedle patch works in a surprisingly simple way. It creates tiny channels in the skin’s outer layer—the stratum corneum—that allow medicines to enter the system. They have better drug loading capability than coated microneedles and “other positive attributes that make it an ideal delivery system, including simple methods of fabrication and disposal, and abundantly available materials.”
Microneedles deliver treatments faster than oral methods and provide “affordable, noninvasive, painless, simple, and self-administered techniques that may prolong release of drugs to enhance patient compliance.”
Transdermal drug delivery avoids the first-pass effect through the liver and eliminates challenges associated with fear of needles and difficulty swallowing.
From vaccines to chronic diseases, dissolving microneedles can make treatment more accessible, less expensive, and more effective.
Recent Advances in Microneedle Technology
How microneedles are made is a critical factor in advancing treatment potential.
Mould-based fabrication is the most common method. It uses a mould formed by copying the metal or stainless-steel master structure to reproduce the microneedles at scale.
Mould-free techniques like 3D printing can overcome obstacles “in the fabrication of MNs with complex geometric shapes and multifunctional performance.“ 3D technology is gaining acceptance and is recognized by the FDA.
Until recently, there were six main types of microneedles (see below).
Advanced technology and new manufacturing methods are emerging, opening new treatment opportunities. The latest advances can fabricate a dissolving microneedle patch using only the therapeutic agent. This eliminates the need for additional ingredients to stabilize or strengthen the product.
Manufacturing technology helps us edge closer to victory in fighting diseases.
Microneedles to Combat Cardiovascular Disease
Cardiovascular diseases “are the leading cause of death globally,” accounting for approximately 17.9 million deaths in 2019. While genetics come into play, unhealthy diet, physical inactivity, tobacco use, and harmful alcohol consumption are leading causes. Changing your lifestyle and diet can reduce or prevent cardiovascular disease.
Carvedilol, a common oral medication, has 25% bioavailability after the first-pass effect. A dissolving microneedle patch loaded with carvedilol could combat cardiovascular diseases, improve health outcomes, and significantly reduce the burden on medical professionals and hospitals.
A Dissolving Microneedle Patch to Treat Skin Cancer
Melanoma, the most severe form of skin cancer, is reportedly “increasing in people under 40, especially women.” The most common treatments are invasive, usually involving surgically removing the affected area plus a small margin of the normal skin next to it.
Treating certain types of melanoma with a dissolving microneedle patch using Rose Bengal for “the topical management of melanoma” could reduce surgery waitlists and speed treatment times by “releasing the active cargo directly to the target site.”
Preventing Exposure to HIV
85.6 million people have been infected with Human Immunodeficiency Virus (HIV), and an estimated 40.4 million people have died of HIV since the beginning of the epidemic. Almost two-thirds of those living with HIV are in low-income countries, mainly sub-Saharan Africa.
Approved anti-retroviral drugs are expensive, and patient compliance tends to be low. The pre-exposure prophylaxis drug long-acting cabotegravir can prevent the spread of HIV, and its approval in the US, Australia, and Zimbabwe marks a turning point in treatment.
However, the long-acting cabotegravir (CAB-LA) is administered by an invasive hypodermic needle, and finding health care professionals to give the jab can be challenging in many countries.
Researchers developed a microneedle patch “with unique design and novel formulation as a potential alternative self-administrated intradermal delivery system for CAB.”
Successful laboratory results signal the urgency to advance to the clinical testing stage.
Treating Skin and Soft Tissue Infections
The number of hospital patients with soft skin and tissue infections is rising. One of the go-to drugs for treatment, metronidazole (MTZ), has limitations, particularly when tackling deeper conditions.
A dissolving microneedle patch that reformulated MTZ into a nanosuspension reportedly delivered “the nitroimidazole antibiotic across all strata of the skin, resulting in a delivery efficiency of 95% after a 24-hour permeation study.”
Source: Q. K. Anjani et al., Metronidazole nanosuspension loaded dissolving microarray patches: An engineered composite pharmaceutical system for the treatment of skin and soft tissue infection.
Future soft tissue infections may be cured with a dissolving microneedle patch.
Tuberculosis
Tuberculosis is a highly infectious airborne disease responsible for 1.3 million deaths in 2022. Although TB is treatable and curable, it requires a “6-month course of 4 antimicrobial drugs that are provided with information and support to the patient by a health worker or trained volunteer.”
Antibiotic treatment can be expensive, and extended exposure risks liver damage and poor balance in the gut microbiome.
A hydrogel-forming microneedle patch demonstrated “the versatility of hydrogel formulations to deliver a TB drug regime using MN arrays. Accordingly, this is a promising approach to deliver high doses of TB drugs.”
A dissolving microneedle patch to treat tuberculosis could help the WHO achieve its End TB strategy by 2035.
The Vitropep Solution
Vitropep is developing commercial therapeutic peptide-based treatments using a dissolving microneedle patch. Founder Christophe Tarabout discovered that some peptides can be dried in a stable state, making them ideal candidates for microneedle applications. The company has filed a patent application for an innovative, stabilized, dissolving microneedle using therapeutic peptides.
Vitropep is focused on using its patent-pending concentrated, stabilized microneedles to help people with chronic diseases.
Vitropep’s advanced dissolving microneedle fabrication process eliminates the need for polymers and other additives. The result is a dissolving microneedle patch that can carry up to 90% of the API for efficient drug delivery.
There is an increased urgency to achieve regulatory approval of microneedles for a range of treatments. Until this becomes a reality, we are stuck with hypodermic needles.
Vitropep is creating a future where doctor's appointments are positive experiences devoid of the stress and fear traditionally linked to needles. Dissolving microneedles pave the way for a more patient-centric approach to health care, ensuring better compliance and improved outcomes.
The transition from hypodermic needles to dissolving microneedles is not just a technological shift; it's a paradigm shift in how we perceive and receive medical care. Microneedles are small and easy to ship without expensive temperature limitations, improving global access to critical medications.
Imagine a future where our children do not experience the stress and pain of hypodermic needle injections—a future where treatments can be administered in the comfort of your home.
Advanced microneedle technology improves treatment and health care outcomes.