Iodine loaded nanoparticles with commercial applicability increase survival in mice cancer models with low degree of side effects

BACKGROUND: The recorded use of iodine in medicine, dates to 5000 BC. Molecular iodine (I(2)) has been claimed to exert an antineoplastic effect that triggers apoptotic and re‐differentiation mechanisms in different types of cancer cells in animal studies. Hitherto, all experiments published have been carried out with I(2) diluted in water preparations resulting in the administration of ionized iodide, either alone or in combination with low levels of I(2). To maximize the levels of I(2) by avoiding water solutions we have managed to develop a colloidal nano particle (NP) loaded with I(2) with a Z‐average of 7‐23 nm with remarkable stability, preferable osmolality and commercial applicability. AIMS: Here we report the results from formulation and pre‐clinical studies with the rationale: a) to find a tolerable dose of the I(2) NP system delivered intravenously or per‐orally, and b) to determine if the tolerable doses are efficacious in murine models of cancer. METHODS AND RESULTS: A novel drug delivery system with I(2) NP was formulated and murine cancer models with CT26, MDA‐MB‐231 and LL/2 cells were used to analyse the efficacy. Despite the formulation challenges we were successful in constructing stable NPs loaded with I(2) which have convincing commercial applicability. We conclude that administration of the NP I(2) drug delivery system: 1. Blunted tumour growth in a xenograft breast cancer model; 2. Had a significant effect on survival in the orthotopic, syngeneic lung metastasis model; 3. Showed reduced tumour burden in post‐mortem evaluation and; 4. Was associated with low degree of side effects. CONCLUSIONS: Taken all together, our findings indicate that the NP I(2) drug delivery system may serve as a novel effective cancer treatment with low degree of side effects. This is something which needs further exploration including confirmation in future clinical trials.