A team of scientists in Australia, led by Indian-origin researchers, has developed a groundbreaking once-weekly injectable formulation that could transform treatment for over eight million people living with Parkinson's disease worldwide. The innovation from the University of South Australia (UniSA) delivers two essential Parkinson's medications—levodopa and carbidopa—through a single injection, potentially replacing the burden of multiple daily pills.
The breakthrough, detailed in the journal Drug Delivery and Translational Research, addresses common challenges faced by Parkinson's patients, including frequent dosing, difficulty swallowing pills, and inconsistent drug levels that can lead to erratic symptom control and increased side effects.
Revolutionary Drug Delivery System
The long-acting, biodegradable injectable gel maintains steady therapeutic levels of medication over seven days. Professor Sanjay Garg, lead researcher and director at UniSA's Centre for Pharmaceutical Innovation, explained the significance of this development.
"Levodopa is the gold standard for Parkinson's treatment, but its short half-life necessitates multiple doses each day," Garg said. "Our goal was to simplify treatment, improve compliance, and ensure more consistent therapeutic outcomes. This injectable could truly be a game-changer in Parkinson's care."
The injectable gel combines a US FDA-approved biodegradable polymer, PLGA, with Eudragit L-100, a pH-sensitive polymer, to achieve controlled and sustained drug release. This combination allows for steady release of both levodopa and carbidopa over a week, helping maintain consistent plasma levels and reducing risks associated with fluctuating drug concentrations.
Clinical Performance and Safety Profile
Extensive laboratory tests confirmed the system's effectiveness and safety. The formulation steadily releases over 90% of levodopa and more than 81% of carbidopa across seven days. The biodegradable nature of the system ensures safety, with the implant degrading by over 80% within a week and showing no significant toxicity in cell viability tests.
The formulation can be easily administered through a fine 22-gauge needle, making it minimally invasive and eliminating the need for surgical procedures. This approach addresses the particular challenges faced by elderly patients or those with swallowing difficulties, who often struggle with frequent pill regimens that can result in missed doses and reduced treatment effectiveness.
Broader Therapeutic Applications
Beyond Parkinson's disease, Professor Garg highlighted the broader potential of this delivery system. "This technology could be adapted for other chronic diseases such as cancer, diabetes, neurodegenerative disorders, pain management, and chronic infections, where long-term, consistent drug delivery is critical," he noted.
The innovation marks a major step forward in non-invasive, sustained-release treatments, offering renewed hope to millions worldwide battling long-term conditions that demand frequent medication. By shifting to a once-weekly injection, the new method could vastly improve both patient adherence and quality of life for those managing chronic conditions requiring consistent therapeutic drug levels.
