Osaka-based Santen has seen some positives mixed with some negatives for its phase 3 ophthalmology program, but believes it has enough to warrant an NDA with the U.S. regulator.
The phase 3 Sakura test was treating patients with Opsiria (sirolimus intravitreal injection) as a monotherapy across various doses (44 µg, 440 µg and 880 µg) in those with noninfectious uveitis of the posterior segment, a condition that can cause blindness.
The Japanese biopharma said that, overall, the program met its objective, by showing its orphan tagged candidate at the 440-µg dose “can effectively and safely reduce intraocular inflammation (as measured by vitreous haze).”
It was however a tale of two studies: the first, Sakura Study 1, “established the efficacy and safety of Opsiria as a potential treatment for non-infectious uveitis of the posterior segment,” according to the co’s topline data.
But in Study 2, the difference in the effect (of vitreous haze) between the low dose of the drug (44µg) and the 440µg dose was not statistically significant, “though clinical findings provide supportive evidence confirming the efficacy of the product,” the company said. Further detailed data were not given.
Santen is however still forging ahead, saying it is looking at the “totality of the data” from Sakura, and using these as the basis for its NDA to the FDA next year.
“Opsiria will address a significant need in the management of non-infectious uveitis of the posterior segment as a locally-delivered option for this orphan disease. Santen is looking forward to filing an NDA in the U.S. in early 2017,” said Naveed Shams, CSO and head of global R&D at Santen.
But this comes after the company withdrew its European marketing app back in May, saying that it needed to submit new data to address concerns coming out of the regulator, namely that the data from the submitted study were “not sufficient to demonstrate the benefit of Opsiria, particularly in European patients.”
The treatment is a first-in-class intravitreal, locally delivered, targeted immunoregulator. It works by regulating the immune system through the inhibition of Mtor.
This acts by interrupting the inflammatory cascade that leads to T cell activation, differentiation and proliferation, and production of interleukin-2 (IL-2), as well as other pro-inflammatory cytokines and, also, promoting immune tolerance by inducing T regulatory cells.
Its key ingredient, sirolimus, has been used as an organ rejection med by Pfizer under the brand name Rapamune, and last year also got the nod to treat lymphangioleiomyomatosis (LAM), a rare, progressive disease that affects the lungs, kidneys and lymphatic system.