Eyeworld

EW INTERNATIONAL 88 February 2015 by Matt Young and Gloria D. Gamat EyeWorld Contributing Writers option with substantial benefits over eye drops," enrolled 6 subjects with a diagnosis of ocular hypertension (OHT) or primary open-angle glau- coma (POAG). Findings of this open-label, pilot study (the first-in-human evaluation of liposomal latanoprost delivery system) were published in Drug Delivery and Translational Research in March 2014. Significant IOP-lowering effect Using liposomal latanoprost on glaucoma patients, the research team found that IOP lowering was immediately observed following subconjuctival injection. Within 1 hour after injection, the mean IOP decreased from a baseline IOP of 27.55±3.25 mm Hg to 14.52±3.31 mm Hg (range 10–18 mm Hg), which represent- ed a mean decrease of 13.03±2.88 Application of extended- release nanomedicine in ophthalmology explored T here are more than 700,000 articles listed in Google Scholar related to studies done using liposomes. Liposome technology, which utilizes a capsule composed of lamellar phase lipid bilayer encap- sulating a drug, is currently being used and developed in other medical fields, from gene therapy to skin care. Also, liposomal delivery of certain anti-cancer drugs has been used to target various malignancies. This technology has now come to ophthalmology in the form of liposomal latanoprost, a new nanomedicine jointly developed by scientists from Nanyang Techno- logical University (NTU, Singapore) and the Singapore Eye Research In- stitute (SERI). It is the first reported extended-release nanomedicine in the ophthalmic field. How liposomal latanoprost works This promising treatment involves a painless subconjunctival injection that delivers millions of nanosized capsules that release anti-glaucoma drugs slowly over a period of several months. "Ten percent of blindness from glaucoma is caused by poor adher- ence to prescribed dosages of the eye drops," said Tina Wong, FRCOphth, associate professor, Duke NUS Graduate Medical School, Singapore, senior consultant ophthalmologist of the glaucoma service, Singapore National Eye Centre (SNEC), and head of the Ocular Therapeutics and Drug Delivery Research Group at SERI. "We know how difficult it is for patients to take eye drops, and this can be solved by taking the pa- tient out of the management loop." In a pilot safety and feasibility study with 6 patients conducted at SNEC, liposomal latanoprost is said to have yielded exceptional results; the researchers found the new ther- apy to be safe and effective in the treatment of glaucoma—although so far in a limited patient population. The study, titled "Nanomedi- cine for glaucoma: sustained release latanoprost offers a new therapeutic Liposomal injection may replace IOP- lowering eye drops in glaucoma patients I have a confession to make. I have only rarely finished a complete course of antibiotics exactly as prescribed. I don't consider myself noncompliant, just busy and perhaps a little forgetful when it comes to taking medications. I can only imagine how difficult it must be for my patients to take their eye drops, twice a day, every day. An effective long-acting medication for glaucoma treatment would be a welcome option for many patients. Presented here are early clinical results with the first extended release nanomedicine for use in ophthalmology, liposomal latanoprost. Could this herald a new era in the treatment of glaucoma? The concept is compelling, and if it proves to be effective, it will be an important breakthrough. John A. Vukich, MD, international editor " We know how difficult it is for patients to take eye drops, and this can be solved by taking the patient out of the management loop. " –Tina Wong, FRCOphth International outlook mm Hg (range 9–17 mm Hg) or 47.43%±10.05% (range 37–63%). IOP reduction (≥20% IOP reduction, P=0.001 to 0.049) was found to be clinically and statistically significant throughout the 3-month period after injection. "Within an hour following injection, there was a reduction in the IOP of more than 50% from baseline observed in some of the patients," Prof. Wong said. "A mean IOP reduction of greater than 20% was maintained and achieved for the 3 months of the study period. This provides encouraging initial results in this small study. A larger number of patients needs to be evaluated with this promising drug delivery system." Prior to clinical study, Prof. Wong and her teams at SERI and NTU reported the therapeutic effect of the liposomal nanocarrier for Publications • Sustained drug release in nanomedicine: A long-acting nanocarrier-based formulation for glaucoma. Natarajan JV, et al. ACS Nano 2014 • Nanomedicine for glaucoma: liposomes provide sustained release of latanoprost in the eye. Natarajan JV, et al. Int J Nanomedicine 2012 • Sustained release of an anti-glaucoma drug: demonstration of efficacy of a liposomal formulation in the rabbit eye. Natarajan JV, et al. PLoS One 2011 • Patient acceptance and attitude toward an alternative method of subconjunctival injection for the medical treatment of glaucoma. Chong RS, et al. J Glaucoma 2013

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