pSivida announced positive top line results from a phase 2 investigator-sponsored study of Medidur for uveitis affecting the posterior of the eye (posterior, intermediate and pan-uveitis), according to a company news release.
Glenn J. Jaffe, MD, Robert Machemer Professor of Ophthalmology at Duke University School of Medicine in Durham, North Carolina, presented the top line results during an oral abstract session at the American Society of Retina Specialists in Vienna, Austria, reporting a statistically significant reduction in recurrence of uveitis and a statistically significant improvement in visual acuity in eyes treated with Medidur.
In the 3-year, ongoing study, 11 participants with recurrent non-infectious intermediate, posterior or pan uveitis were randomized to receive a masked low or a high dose of Medidur. (pSivida is studying only the low dose of Medidur in its phase 3 clinical trials.) Fellow eyes with uveitis were treated with standard of care, which included steroid eye drops. At the most recent follow-up visit reported, participants have been followed for between 12 and 24 months.
Through the last follow-up visit reported, none of the eyes treated with Medidur had any recurrence of uveitis, while fellow eyes treated with standard of care averaged 2.33 recurrences. The difference between treatment with Medidur and standard of care was statistically significant (P=0.014).
Eyes treated with Medidur experienced a significant improvement in visual acuity, gaining an average of 17 letters from baseline letters at 12 months on the Snellen eye chart (P=0.014 at 12 months). At the last follow-up visit reported, the average gain from baseline in Medidur-treated eyes was over 20 letters, while eyes treated with standard of care declined an average of 10 letters.
The most common adverse event in study eyes was elevated IOP. Through the last follow-up visit reported, three study eyes developed elevated IOP and were treated with eye drops, with filtering procedures subsequently performed in two of these eyes. However, those two eyes still gained an average of over 25 letters from baseline at the last observation. The study remains masked as to the dosage so results cannot yet be separated for the low and high doses of Medidur.
pSivida recently announced that at three months in its first phase 3 trial, which is testing only the low dose of Medidur, only 4% more study eyes (2/3 of which received Medidur) experienced elevated IOP than the fellow non-study eyes (none of which received Medidur). Initial IOP elevation is an indication of the likelihood of subsequent clinically significant IOP increases. The minimal difference observed in elevated IOP in the assessment suggests highly favorable results for a key safety measure of the trial, the number of eyes that develop clinically significant increases in IOP within 12 months of receiving Medidur relative to control eyes.
“The results in Dr. Jaffe’s study are very dramatic. The efficacy of Medidur in controlling uveitis and restoring visual acuity was spectacular. At the extreme, in addition to completely arresting any recurrence of uveitis, Medidur restored vision to two eyes that were legally blind at baseline, improving from 20:400 to 20:25 and from 20:500 to 20:40 at the last follow-up visit. We look forward to the unmasking of the data to view the results for the low dose of Medidur we are studying,” Dr. Paul Ashton, president and chief executive officer of pSivida, said in the news release.
About the Phase 2 Trial
The investigator-sponsored phase 2 study is evaluating the tolerability, safety, and benefits of high- and low-dose Medidur in recurrent non-infectious posterior, intermediate or pan-uveitis. Eleven enrolled participants were randomized to receive a masked low or a high dose of Medidur in the worse eye. (Only the low dose is being studied in pSivida’s phase 3 trials.) Fellow eyes with uveitis are treated with standard of care. Eyes are observed on the day of injection, on days 1, 7, 14, 28, then monthly for up to 6 months, then every 3 months for 18 additional months. For purposes of these results, all participants were followed for a minimum of 1 year, with a mean follow-up duration of 20.5 months. Because the study is ongoing, the dose remained masked, and the results present aggregate data for the low and high dose. Full top-line results of this phase 2 study have been submitted for publication.