No abstract

Sonodynamic therapy (SDT) involves the activation of a non-toxic sensitiser drug using low-intensity ultrasound to produce cytotoxic reactive oxygen species (ROS). Given the low tissue attenuation of ultrasound, SDT provides a significant benefit over the more established photodynamic therapy (PDT) as it enables activation of sensitisers at a greater depth within human tissue. In this manuscript, we compare the efficacy of aminolevulinic acid (ALA) mediated PDT and SDT in a squamous cell carcinoma (A431) cell line as well as the ability of these treatments to reduce the size of A431 ectopic tumours in mice. Similarly, the relative cytotoxic ability of Rose Bengal mediated PDT and SDT was investigated in a B16-melanoma cell line and also in a B16 ectopic tumour model. The results reveal no statistically significant difference in efficacy between ALA mediated PDT or SDT in the non-melanoma model while Rose Bengal mediated SDT was significantly more efficacious than PDT in the melanoma model. This difference in efficacy was, at least in part, attributed to the dark pigmentation of the melanoma cells that effectively filtered the excitation light preventing it from activating the sensitiser while the use of ultrasound circumvented this problem. These results suggest SDT may provide a better outcome than PDT when treating highly pigmented cancerous skin lesions.

Current formulations and dose regimens of hydroxychloroquine (HCQ) put patients at risk of harm. An analysis of clinical trials registered on ClinicalTrials.gov revealed that this may continue as many studies combine HCQ with agents that prolong the QT interval. Further, almost all of the trials registered do not consider dosage adjustment in the elderly, a patient population most likely to require HCQ treatment. Here we describe an inhaled formulation of HCQ which has passed safety studies in clinical trials for the treatment of asthma and discuss how this approach may reduce side-effects and improve efficacy. As this simple formulation progressed to phase II studies, safety data can be used to immediately enable phase II trials in COVID-19.

The cocrystallization of lamotrigine and valproic acid affords an ionic cocrystal with improved dissolution rate and mechanical properties. The multidrug crystal has a stoichiometry that is known to positively impact the pharmacokinetics of the parent compounds. As such, the new form is a suitable epileptic treatment. From a crystal engineering perspective, the structure is sustained by a complex multimolecular motif that includes each conformer in both the protonated and deprotonated state. Statistical and computational analysis reveals that the presence of ancillary H-bond donors in an R1 2(4)­DD (or R2 2(8)­DD) fashion is critical to the ionization state of the components.