In recent years, breakthroughs in nanomedicine technology have unlocked many revolutionary therapeutic pathways. Among these, lipid nanoparticle (LNP) technology has shown great promise in multiple therapies. Advances in medical science have led to the successful integration of lipid nanotechnology into conventional therapy with significant results.
The use of nanoparticles using lipids derived from natural or synthetic forms in the diagnosis, monitoring, control and treatment of diseases is the essence of nanomedicine. One of the main advantages of this technology is that lipid-based nanoparticles can be designed specifically to overcome the limitations posed by the natural biological barriers of the human body, whether systemic or cellular.
LNP in Novel Drug Delivery Systems (NDDS)
Nanoparticle research has gained momentum in recent years with promising results. Among these, lipid-based nanoparticles or LNPs are widely considered to be a drug delivery system of choice. They can be used as vehicles to help facilitate the safe transport of a range of vital therapeutics across membranes to the target site in the body. Their ease and simplicity of formulation, their biocompatibility, their high bioavailability, their ability to increase the stability and solubility of the encapsulated cargo make them very useful in targeted therapy.
Liposomes, which are a subset of LNPs, are also of particular interest. These liposomes range from 100 to 330 nm in diameter. They are small spherical vessels composed of one or more phospholipid bilayers. Liposomes form spontaneously when phospholipids are hydrated with water and closely resemble the structure of cell membranes. Due to their unique structure, a variety of drugs, including many hydrophilic, amphiphilic, and hydrophobic active molecules, can be conveniently encapsulated in these structures and transported to target sites in the body.
The protective phospholipid shield traps unstable molecules or substances, thereby protecting them from enzymes, fluctuating pH levels, free radicals in the body and delivering them to specific target cell sites, thus making them ideal as drug carriers.
Applications in nanomedicine
Nanoparticles have caused a radical change in the biomedical and therapeutic fields. Active molecules used for cancer treatment can be encapsulated in liposomes and efficiently delivered to target cancer cells. Liposomes up to 100 nanometers easily penetrate tumors and are stable for longer periods. Antibodies bound to modified liposomes are able to target tumor-specific antigens and then deliver drugs to the tumor. Due to the biostability factor, the drug is delivered to the specific cancer cell, thereby reducing side effects on surrounding cells and tissues.
These nanoparticles can target cancer cells by crossing the blood-brain barrier. They are therefore widely taken into account in the treatment of brain tumours. Doxorubicin encapsulated in a closed lipid sphere (liposome) is the first clinically approved PEGylated nanoliposome for the treatment of cancer.
Lipid nanoparticles have offered hope for increased bioavailability of drugs as well as many diagnostic agents. They have increased potential in the treatment of atherosclerosis. The therapeutic index of some cardiovascular drugs is known to be increased by liposomes. More recently, the use of long-circulating liposomes has also gained importance in the treatment of cardiovascular diseases. The process involves coating the liposomes with a biocompatible molecule. This helps prevent the destruction of the liposome drug carrier and helps keep it in the system longer for increased effectiveness. During myocardial infarction and atherosclerosis, platelets accumulate. Platelet-targeted liposomal drug delivery may also prove to have potential therapeutic applications in the treatment of atherosclerosis.
Among lipid nanoparticles, liposomes are also being evaluated as potential antimicrobial drug delivery nanosystems. These antibiotic-loaded lipid nanoparticles are envisioned in the treatment of drug-resistant bacterial infections, particularly in ocular, pulmonary, and topical bacterial infections. The use of such liposomes as drug delivery agents offers several advantages such as better protection of antibiotics against degradation due to the body’s defense mechanisms while improving the biodistribution of the drug in the system. These liposomes can selectively target and penetrate bacterial colonies despite all repulsive forces.
This technique is also useful in eliminating intracellular bacterial growth in infected tissues due to increased retention of antibiotics and drug release in a controlled manner with fewer side effects.
Vaccines against covid-19
Lipid nanotechnology is the mechanism that has enabled the creation of highly complex and enhanced vaccine-based delivery systems for mRNA-based Covid 19 vaccines.
In the case of the mRNA-based Covid 19 vaccine, the mRNA strand with an adjuvant (used to stimulate an immune response) is encapsulated into the stable structure or matrix of the nanoliposome. The key protein of SARS COV 2 is encoded in the mRNA strand. The lipid nanoparticle once injected into the body, triggers the production of the spike protein which then deposits on the human cell membrane. It acts as an antigen and triggers an immune response that primes the body’s defense mechanism in the event of an actual infection. Lipid Nanoparticles or LNPs provide stability and protection to the mRNA strand throughout the administration process and ensure a more efficient and enhanced immunogenic response of the vaccine.
LNPs pave the way for developments in advanced medicine, but with challenges
Nanotechnology is an exciting platform with enormous potential to impact the delivery of a wide range of therapeutic small molecules, genes, RNAs, peptides, diagnostic imaging agents and the list can go on. . The advantages of these nanocarriers are their ability to improve the overall pharmacokinetic properties of the drug without hampering its molecular structure, their enhanced tissue targeting ability as well as their ability to overcome all biological barriers within the system.
The last decade has seen the translation of several applications of nanomedicine into clinical practice. However, achieving comprehensive regulation for nanomedicines with the development of clear guidelines and protocols is still a long way to go. Barriers to large-scale production, scalability, high cost of production as well as difficulties encountered in quality control analysis regarding consistency of end product stability and storage stability are some of the major challenges that need to be addressed systematically.
Nanomedicines have significant potential to increase pharmaceutical market growth and improve health benefits. The commercialization of nanomedicines is highly dependent on several regulatory factors based on government policies. However, given the right funding, opportunity, and research momentum, this technology holds great promise in treating complex health conditions.
Arun Kedia, Managing Director, VAV Life Sciences
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