pSivida Announces Interim Results from the Three-Month Readout of the Human PK Medidur™ FA Study
News Jun 30, 2008
pSivida Corp. has reported the interim three-month safety and efficacy results from the first human pharmacokinetic (PK) study of Medidur™ FA, in patients with Diabetic Macular Edema (DME). This Phase II study is designed to support the ongoing pivotal Phase III clinical trial of Medidur in DME.
Medidur releases the drug Fluociniolone acetonide (FA) directly into the eye to treat DME. The Phase II study described here is primarily designed to assess systemic exposure to that drug after administration of Medidur into the eye. The study is secondarily designed to provide information on the safety and efficacy of Medidur in a DME population.
A total of 37 subjects were enrolled in this trial, 20 patients on the low dose (an approximate 0.23µg per day dose) of Medidur and 17 patients on the high dose (an approximate 0.45µg per day dose) with the same inclusion/exclusion criteria as the ongoing Phase III study.
The three month interim readout from the PK study indicated 20 percent of the low dose patients and 18 percent of the high dose patients showed an improvement in best-corrected visual acuity (BCVA) of 15 letters or greater from baseline on an eye chart.
In addition, both the low dose and the high dose of Medidur resulted in a significant reduction in retinal thickness as compared to the baseline.
From a safety perspective, no adverse events related to intraocular, or inner eye, pressure were seen in the low dose patients, while 12 percent of the high dose patients experienced intraocular pressure increases of greater than 30 mmHg.
Additionally, the only adverse event related to cataract formation was reported in a patient in the high dose group.
The early readout from this PK study provides further insight into the dose-response of FA in the treatment of DME. By comparison, Retisert® intravitreal implant, which releases FA at an initial rate of 0.6 µg per day, was also studied in a DME population.
Retisert data presented at the ARVO conference in 2004 and 2005 showed that at 6 months between 15% and 20% of DME patients receiving Retisert gained 15 letters from baseline on an eye chart and after 2 years this increased to 27% but there were some steroid related side effects, particularly cataract and elevation of IOP.
“We are very excited by the early results of this study which supports our hypothesis that lower doses of FA delivered via our Medidur system will provide visual acuity improvements whilst reducing the risk of ocular side effects commonly associated with the use of corticosteroids,” said Dr Paul Ashton, Managing Director, pSivida Corp.