Liposomes are tiny, sphere-shaped sacs that researchers have increasingly investigated for their drug-delivery potential. They particularly see opportunities to use them in precision medicine because liposomal methods shield the drug with a lipid bilayer until it reaches the desired location. Then, that barrier disintegrates, stimulating the contents’ release. Here are some recent examples of liposomal drug delivery progress.
Improving treatment success, reducing antibiotic resistance
When people feel sick, many typically request antibiotics from their health care providers. That approach is only appropriate in specific circumstances, although some physicians overprescribe antibiotics to reduce the likelihood of patient complaints. Unfortunately, this trend has worsened antibiotic resistance, making some bacterial strains more resistant to the interventions that formerly combated them.
However, researchers have developed a liposomal system for treating streptococcus pneumonia, which causes bacterial pneumonia, sepsis and meningitis. Their innovation only releases antibiotics after detecting toxins produced by the targeted bacteria.
The researchers said this strategic dosing should reduce unpleasant side effects caused by unnecessary antibiotic use. Additionally, the patient only needs to take this antibiotic as a single dose, and they get an amount tailored to meet their needs. That convenience eliminates instances where people must remember to take their medication with food or at certain times.
This team also conducted a second study involving this drug delivery method to treat Gardnerella vaginalis, commonly associated with bacterial vaginosis, showing the possible versatility. They even explored avenues beyond drug delivery, investigating whether adding this technology to processed meat packages could extend their shelf life. Although the work is still in the early stages, those involved hope to commercialize this new method of administering antibiotics.
Developing an enzymatic cocktail
Medical researchers must frequently adopt problem-solving mindsets, using their skills and knowledge to address known challenges. One team recognized that some chemical antibiotics have become less effective due to growing resistance. Then, they examined creating something to target numerous mycobacterial species. The associated infections are incredibly challenging to treat. Some patients must undergo years of toxic treatments, and they may begin testing positive again after long periods of negative results.
However, this team took a biological approach rather than the conventional chemical one, creating a cocktail that uses liposomal drug delivery methods to target two dangerous pulmonary lung diseases. Their innovation targets and breaks down the mycobacteria cell envelope, preventing the bacteria from remaining viable.
Additionally, research indicated this cocktail complements many drugs typically prescribed to treat mycobacterial infections and does not cause the unwanted interactions with other medications that some of those interventions do.
Although this example involves a new approach, other liposomal drug delivery efforts expand on what people previously knew. For example, dimethyl sulfoxide is one of the oldest and most widely used permeation enhancers, used to help drugs penetrate the skin and have the desired effects. One study found that dimethyl sulfoxide caused a 30% increase in lipid expansion, and researchers concluded that it made the active ingredient reach its target more effectively.
Such progress opens opportunities for people to pursue other liposomal methods to increase the chances of patients responding well to their prescribed medications.
Finding a more accessible production technique
Research teams are particularly interested in applying liposomal drug delivery options to chemotherapy treatments. This method could send the therapies directly to the targeted cells, leaving the healthy ones untouched. Some people working on these options believe immunoliposomes could be the key because they contain surface-targeting ligands that bind to the antigens on tumor cell surfaces. That attachment mechanism increases the time tumor cells absorb the chemotherapy drug, making it more effective.
However, creating immunoliposomes is complex, requiring processes with several steps. People have demonstrated immunoliposomes’ potential in laboratories since the 1980s, but manufacturing challenges are one of the main reasons they are not yet commercially produced.
One researcher made a breakthrough by publishing his outline for a simple and eco-friendly single-step production process. This process adds engineered chimeric nanobodies, which are sticky on one end and so small that 2,500 of them can become part of one 100-nanometer liposome.
This method is faster and less expensive than current production methods. Additionally, the researcher believes the nanobodies on the liposome’s surface could create a protective layer, stopping the patient’s body from clearing the medication too quickly and increasing how long it stays in the bloodstream.
This manufacturing process does not require the liposomal drug administration to contain polyethylene glycol. Many traditional options contain it, but the compound can have unwanted effects on patients and sometimes even cause death. Federal regulators in the United States require additional monitoring for drugs containing it. However, the lack of it in this method could make it more commercially viable and enable it to get approved more quickly.
Pushing liposomal drug delivery forward
These fascinating examples show how hardworking, dedicated researchers are making meaningful progress in finding better ways to administer the drugs patients need and increase the chances of favorable outcomes. Such improvements could shorten therapeutic timelines, helping people feel better faster.
Opinions expressed by SmartBrief writers are their own.
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