PRNewswire
Sirolimus Demonstrates Favorable Safety Profile and Improvements in Visual
Acuity
UNION CITY, Calif., Feb. 25 /PRNewswire/ -- MacuSight(TM), Inc., a
developer of innovative therapeutics for the treatment of severe ocular
diseases and conditions, today announced positive preliminary data from a
Phase 1 study of its lead product candidate in patients with wet
(exudative) age-related macular edema (wet AMD). Similar to its Phase 1
study in patients with diabetic macular edema (DME), preliminary results
from this prospective study of 30 patients demonstrated that MacuSight's
proprietary formulation of sirolimus (rapamycin) was safe and
well-tolerated in all doses tested with two different routes of
administration. In addition, improvements in visual acuity consistent with
anatomical retinal changes were observed following a single administration
of sirolimus. These findings were presented at Bascom Palmer Eye
Institute's Angiogenesis, Exudation and Degeneration 2008 conference by
Pravin U. Dugel, M.D., member of MacuSight's scientific advisory board,
managing partner, Retinal Consultants of Arizona, Phoenix AZ, clinical
instructor, vitreoretinal diseases and surgery, department of
ophthalmology, University of Arizona, and the study's lead investigator.
As part of the design of this randomized, open-label study,
investigators evaluated the safety, tolerability and biological activity of
sirolimus when delivered by either a subconjunctival or intravitreal
injection. The trial showed no evidence of increased intraocular pressure,
inflammatory response to treatment, or indication of progression of
cataracts. Furthermore, the study provided an initial assessment of
sirolimus' biological activity in AMD with patients demonstrating
improvements in visual acuity despite extended duration of disease prior to
entering the study. Additionally, patients also experienced anatomical
improvements as demonstrated by a reduction in retinal thickness. These
preliminary findings demonstrated that sirolimus administered via
subconjunctival injections was as effective, if not more so, than sirolimus
administered via intravitreal injections.
Intravitreal injections (into the central cavity of the eye), while the
standard route of administration for current therapies, are uncomfortable
for many patients and are accompanied by the risk of serious infection in a
small percentage of patients. In contrast, subconjunctival injections (just
under the outer layer over the white of the eye) are designed to offer
physicians and patients a less invasive and more convenient procedure.
"We are pleased to see the trial's positive safety and tolerability
measures combined with promising indications of efficacy marked by
consistent and rapid improvements in visual acuity and retinal thickness
following a single injection of sirolimus," said Dr. Dugel. "Furthermore,
the fact that patients in the subconjunctival injection arms exhibited
efficacy measures equal to, and in some cases greater than, those in the
intravitreal injection arms indicates that this product also has the
potential to offer physicians and patients significant safety and ease of
administration advantages."
Also at the Angiogenesis, Exudation and Degeneration 2008 conference,
Mark Blumenkranz, M.D., chairman of MacuSight's scientific advisory board
and professor and chairman of the department of ophthalmology, Stanford
University School of Medicine, presented the final results of MacuSight's
Phase 1 study of sirolimus in patients with DME. These findings corroborate
the preliminary results which MacuSight announced in October 2007 at the
40th Annual Meeting of The Retina Society.
"We are very encouraged by this study's findings as they provide a
compelling demonstration of sirolimus' potential therapeutic activity in
patients with wet AMD. This is particularly exciting as these results are
consistent with previously announced Phase 1 data for our sirolimus product
in patients with diabetic macular edema," stated Joel Naor, M.D., chief
medical officer of MacuSight. "Based on the positive findings from both our
wet AMD and DME studies, we are preparing to initiate Phase 2 trials in
both of these important indications, as well as additional ocular diseases
and conditions."
MacuSight intends to complete its collection and analysis of all data
from its wet AMD trial and present final findings at the Retinal Physician
Symposium in Naples, Florida in May 2008.
About Sirolimus
Sirolimus, originally known as rapamycin, is a highly-potent,
broad-acting compound that has demonstrated the ability to combat disease
through multiple mechanisms of action including immunosuppressive,
anti-angiogenic, anti- migratory, anti-proliferative, anti-fibrotic and
anti-permeability activity. Based on the versatility associated with these
multiple mechanisms of action, MacuSight believes that its sirolimus
product may serve as a potentially highly-efficacious therapeutic for a
wide range of ocular diseases and conditions, including the treatment and
prevention of wet AMD.
As the active pharmaceutical ingredient in the FDA-approved products
Rapamune(R) and CYPHER(R) Sirolimus-eluting Coronary Stent, sirolimus has
been safely administered to humans for more than eight years. MacuSight has
developed a proprietary minimally-invasive, sustained administration
approach for its novel liquid sirolimus formulation which it believes will
provide the product with significant competitive advantages related to
convenience, ease- of-use, compliance and safety.
About Wet Age-Related Macular Degeneration (AMD)
Age-related macular degeneration (AMD) is the leading cause of visual
loss in the western world. This disease of the aging eye results in loss of
the sharp, central vision that is necessary for clearly seeing objects and
undertaking routine tasks including reading and driving. AMD occurs in both
wet and dry forms, with the wet form accounting for the vast majority of
cases of AMD-related blindness and progressing much more rapidly than dry.
It is presently estimated that wet AMD affects approximately two
million Americans. Growing at an annual rate of approximately 13%, it is
expected that the total number of patients will exceed 3.5 million by 2010.
Industry experts expect the total U.S. market opportunity for wet AMD
therapeutics to reach close to $2 billion by that time.
About MacuSight
MacuSight is a privately-held pharmaceutical company focused on
developing innovative therapeutics for the treatment of severe ocular
diseases and conditions. The company is dedicated to preserving patients'
vision by identifying known, highly-potent and broad-acting small molecule
drug compounds that may possess efficacy in treating and/or preventing
diseases or conditions of the eye. As part of its unique product
development philosophy, MacuSight also concentrates on the optimal delivery
of these compounds into the eye. By combining its compounds with innovative
delivery approaches, the company strives to optimize the efficacy, safety,
convenience and cost- effectiveness of its product candidates.
The company's lead development program is centered on advancing
sirolimus (rapamycin) as a potential next-generation therapeutic for the
treatment and prevention of wet age-related macular degeneration (wet AMD)
and the treatment of diabetic macular edema (DME), a manifestation of
diabetic retinopathy.