M Kaur1; V YARDLEY2; M Li1;
1 De Montfort University, UK; 2 London School of Hygiene & Tropical Medicine, UK
DiscussionBioavailability improvement of Artemisinin through cocrystal approach: in-vivo and in vitro studies Malaria, caused by the protozoal parasites of the genus Plasmodium, is a potentially life-threatening disease which causes more than 200 million clinical cases and 450,000 deaths annually. Artemisinin is the preferred treatment for malaria, which is both effective and well tolerated in patients, but has the problem of low bioavailability after oral administration due to its low solubility. This leads to inadequate treatment. Additionally the complicated chemical structure structural of artemisinin requires costly modification. Although many potent derivatives of artemisinin with better bioavailability have been found, they are all associated with toxicity, metabolic instability and short half-life. A substantial amount of research is ongoing in order to develop methods that can overcome issues related to the solubility and dissolution rates of drugs. In recent years, pharmaceutical cocrystals have attracted remarkable interest for enhancing solubility and dissolution rates of poorly water soluble drugs. A pharmaceutical cocrystal is formed by combining an active pharmaceutical ingredient (API) with an inactive coformer through a specific stoichiometric composition. The aim of this work was to improve the bioavailability of Artemisinin through a cocrystal approach. The API, Artemisinin, was formulated with orcinol and resorcinol coformers to obtain two artemisinin cocrystals. The performance of the artemisinin drug and its two cocrystal based formulations have been investigated through in vitro studies such as dissolution and permeability tests. The anti-malarial activity of drug alone and two cocrystals was tested against Plasmodium berghei infection in female BALB/c mice in a 4-day Peter’s test. The in vivo study results have shown a significant improved parasite clearance with cocrystal formulations as compared to the artemisinin drug alone. The artemisinin concentrations in serum samples were tested using LC-MS/MS and the results showed higher artemisinin concentration in serum for both cocrystal formulations, as compared to the artemisinin drug alone. Through the study artemisinin cocrystal formulations would open new opportunities for development of novel anti-malarial medicines.
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