InSite Vision Incorporated announced positive top-line results from a phase II pharmacokinetic (PK) clinical study comparing the tissue penetration profile of InSite Vision's BromSite (ISV-303) with ISTA Pharmaceuticals' Bromday (bromfenac ophthalmic solution) 0.09 per cent. BromSite combines a lower dose (0.075%) of the Non-Steroidal Anti-Inflammatory Drug (NSAID) bromfenac with InSite Vision's DuraSite drug delivery technology and is intended to reduce the pain and inflammation associated with ocular surgery.
The randomized, double-masked, two-arm study evaluated the aqueous humour concentration of once-daily doses of BromSite versus Bromday in 58 subjects. Subjects were dosed two days before and the morning of the day of cataract surgery. Study results showed that the mean concentration of bromfenac in the aqueous humour of patients in BromSite's group was more than twice greater compared to those patients in Bromday's group with a P-Value of p=0.0032.
The phase II PK clinical study was fully enrolled in six weeks using three sites in the United States under the direct supervision of the InSite Vision clinical department without the use of a contract research organization. BromSite and Bromday were both generally well tolerated and there were no safety concerns or serious adverse events related to either agent. InSite Vision intends to present a final analysis of the BromSite phase II PK clinical trial in conjunction with a future scientific meeting.
In March, InSite Vision reported positive results from a phase I/II clinical trial of BromSite which showed statistically significant superiority compared to vehicle (p=0.0016) for its primary endpoint (the absence of cells in the anterior chamber of the eye at day 15 post surgery). The results of the phase II PK study and the earlier phase I/II clinical trial hold the promise that BromSite may be a commercially superior NSAID for ocular surgical use. The company plans to initiate discussions with the US Food and Drug Administration (US FDA) on the design of the pivotal phase III programme for BromSite. Patent protection for BromSite is expected to extend into 2029.
“We are delighted that the study confirmed the superior penetration of BromSite against the current market leader, Bromday,” said Dr Kamran Hosseini, vice president and chief medical officer of InSite Vision. “Most physicians believe that a higher penetration of bromfenac into the ocular tissues of the eye may reduce the risk of cystoid macular edema, or CME, as a result of ocular surgery. CME is a relatively rare but extremely serious adverse event in ocular surgery that can lead to blindness. We are looking forward to working with the US FDA to finalize the design of the phase III programme for BromSite and currently expect to begin pivotal trials in early 2012.”
Cataract surgery is the most frequently performed ocular surgery in the United States with more than three million procedures annually. Both before and after surgery, anti-inflammatory eye drops are typically prescribed to reduce pain and inflammation and to enhance healing. Anti-inflammatory eye drops are currently used as prophylaxis against CME.
InSite Vision is advancing a second product candidate, known as ISV-101, that utilizes a low-concentration of bromfenac enabled by DuraSite for the treatment of dry eye disease. In January 2011, InSite Vision announced it had filed an Investigational New Drug (IND) application for ISV-101 with the US FDA. The company is positioned to initiate a dose-ranging phase I/II clinical trial in late 2011 or early 2012 to evaluate the safety and efficacy of ISV-101 when administered to patients suffering from dry eye disease. Patent protection for this drug candidate is also expected to extend into 2029.
InSite's DuraSite sustained delivery technology is a patented synthetic polymer-based formulation designed to extend the residence time of a drug relative to conventional topical therapies. It enables topical delivery of a solution, gel or suspension and can be customized for delivering a wide variety of potential drug candidates. The DuraSite platform is currently leveraged in two commercial products for the treatment of bacterial eye infections, AzaSite (azithromycin ophthalmic solution) 1% and Besivanc (besifloxacin ophthalmic suspension) 0.6%. InSite Vision is also applying DuraSite to multiple other clinical- and preclinical-stage product candidates to create a portfolio of novel ophthalmic products.
InSite Vision is advancing new and superior ophthalmologic products for unmet eye care needs.