Sequessome vesicles are ultra-deformable, hydrophilic spheres made from phospholipid and surfactant molecules arranged as a bilayer. Conventional liposomes form rigid bilayer spheres, but the inclusion of surfactants softens the bilayer membrane making Sequessome vesicles flexible, but also stable, allowing them to pass through the skin intact and penetrate deep into the body without requiring injection or skin permeation enhancers. As the aqueous gel dries out, the vesicles are drawn into the intracellular spaces in the skin driven by the hydration gradient. Conventional (rigid) liposomes require injection.
Sequessome vesicles were originally developed as a carrier to deliver active pharmaceutical ingredients (APIs) transdermally – known as Transfersome® vesicles, and were investigated in numerous programmes for different therapeutic targets. One of these programmes investigated ketoprofen to treat symptoms of osteoarthritis and was progressed to the end of multiple Phase III trials. This programme demonstrated drug-free Sequessome vesicles working as well as an oral NSAID (celecoxib) in a twelve week trial – the current FDA and EMA standard for trials in osteoarthritis (OA).
Using data from this programme together with additional research investigating the unique mechanism of action, we have demonstrated that Sequessome vesicles have the ability to address the symptoms of OA in an entirely new way without the use of drugs. This provides a much needed alternative to current approaches, which typically use either non-steroidal anti-inflammatory drugs (NSAIDs) or opioids with a range of serious and potentially fatal side effects, or highly invasive injections directly into the affected joints.
It also offers a treatment that does not interact with other medications, the efficacy of which can be compromised by the use of certain commonly used drugs. This is a particular problem for OA sufferers who are at greater risk of co-morbidities, most notably cardio-vascular problems. Sequessome vesicles' safety profile not only benefits the patients but reduces the overall cost of care, an important advantage for healthcare payors.
Consequently, Pro Bono Bio launched FLEXISEQ® in Europe in 2012 as the first twice daily topical Class II medical device for treating the symptoms of OA, and the first new class of treatment for osteoarthritic joint pain since the launch of the selective COX2 NSAIDs in 1999.