Pancreatic ductal adenocarcinomas respond poorly to chemotherapy, in part due to the dense tumor stroma that hinders drug delivery. Ultrasound (US) in combination with microbubbles has previously shown promise as a means to improve drug delivery, and the therapeutic efficacy of ultrasound-mediated drug delivery is currently being evaluated in multiple clinical trials. However, most of these utilize echogenic contrast agents engineered for imaging, which might not be optimal compared to specialized formulations tailored for drug delivery.
View Article and Find Full Text PDFIntroduction: Acoustic cluster therapy (ACT) comprises co-administration of a formulation containing microbubble/microdroplet clusters (PS101), together with a regular medicinal drug (, a chemotherapeutic) and local ultrasound (US) insonation of the targeted pathological tissue (, the tumor). PS101 is confined to the vascular compartment and, when the clusters are exposed to regular diagnostic imaging US fields, the microdroplets undergo a phase-shift to produce bubbles with a median diameter of 22 µm when unconstrained by the capillary wall. these bubbles transiently lodge in the tumor's microvasculature.
View Article and Find Full Text PDFAcoustic Cluster Therapy (ACT) comprises coadministration of a formulation containing microbubble-microdroplet clusters (PS101) together with a regular medicinal drug and local ultrasound (US) insonation of the targeted pathological tissue. PS101 is confined to the vascular compartment and when the clusters are exposed to regular diagnostic imaging US fields, the microdroplets undergo a phase shift to produce bubbles with a median diameter of 22 µm. Low frequency, low mechanical index US is then applied to drive oscillations of the deposited ACT bubbles to induce biomechanical effects that locally enhance extravasation, distribution, and uptake of the coadministered drug, significantly increasing its therapeutic efficacy.
View Article and Find Full Text PDFAcoustic Cluster Therapy (ACT) represents a novel concept for targeted drug delivery. Ultrasound is applied to activate intravenously administered free-flowing clusters of microbubbles and microdroplets within the target pathology, depositing 20-30 m large bubbles in the microvasculature for 5-10 min. Further application of ultrasound induces biomechanical effects which increase vascular permeability and enhance localized extravasation of coadministered drugs.
View Article and Find Full Text PDFThe blood-brain barrier (BBB) is a major obstacle in drug delivery for diseases of the brain, and today there is no standardized route to surpass it. One technique to locally and transiently disrupt the BBB, is focused ultrasound in combination with gas-filled microbubbles. However, the microbubbles used are typically developed for ultrasound imaging, not BBB disruption.
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