Researchers at several Canadian sites report that exposure to tamsulosin within 14 days of cataract surgery is significantly associated with serious postoperative adverse events. Tamsulosin (Flomax), a medication widely prescribed for urinary symptoms associated with benign prostatic hyperplasia, has been implicated in intraoperative floppy iris syndrome, which can complicate cataract surgery. The Canadian group says theirs is the first study to investigate whether use of tamsulosin or other alpha-blocker drug therapies affect the risk of serious postoperative adverse events. Their report appeared in the May 20, 2009 edition of the Journal of the American Medical Association.
The case-control retrospective analysis used linked health-care databases from Ontario, Canada, and included all men aged 66 years or older who had cataract surgery between 2002 and 2007 (n=96,128). The group compared retinal detachment, lost lens or lens fragment, or endophthalmitis occurring within 14 days after cataract surgery between men treated with tamsulosin or other alpha-blockers and men with no exposure to these medications in the year prior to cataract surgery. They separately examined the association of drug exposure that was either recent (within the 14 days before surgery) or previous (15 to 365 days before surgery).
Overall, 3,550 patients (3.7 percent) in the cohort had recent exposure to tamsulosin and 7,426 patients (7.7 percent) had recent exposure to other alpha-blockers. Two hundred eighty-four patients (0.3 percent) had an adverse event. The researchers randomly matched 280 of the cases to 1,102 controls according to their age, surgeon and year of surgery. Adverse events were significantly more common among patients with recent tamsulosin exposure (7.5 percent vs 2.7 percent; adjusted odds ratio, 2.33; 95 percent confidence interval, 1.22 to 4.43) but were not associated with recent exposure to other alpha-blockers (7.5 percent vs. 8 percent; adjusted OR, 0.91; 95 percent CI, 0.54 to 1.54) or to previous exposure to either tamsulosin (¡Ü1.8 percent vs. 1 percent; adjusted OR, 0.94; 95 percent CI, 0.27 to 3.34) or other alpha-blockers (2.9 percent vs. 2.1 percent; adjusted OR, 1.08; 95 percent CI, 0.47 to 2.48).
Trials Will Assess AzaSite for Blepharitis
Inspire Pharmaceuticals has initiated a Phase II program with AzaSite (azithromycin ophthalmic solution) 1% to pursue a potential indication for the treatment of blepharitis. AzaSite is currently approved by the Food and Drug Administration for the treatment of bacterial conjunctivitis.
Inspire has initiated two Phase II clinical trials. One trial is a randomized, placebo-controlled, multicenter trial at approximately 30 clinical sites evaluating the safety and efficacy of two weeks of treatment with AzaSite compared to placebo in approximately 300 subjects with blepharitis. The second trial is a randomized, placebo-controlled, multicenter trial at approximately 30 clinical sites evaluating the safety and efficacy of four weeks of treatment with AzaSite compared to placebo in approximately 300 subjects with blepharitis. The trials will evaluate various signs and symptoms of blepharitis as well as safety and tolerability. The results from each trial are expected in the first half of 2010.
TearLab Gains FDA Clearance
TearLab Corp. announced FDA 510(k) clearance of its TearLab Osmolarity System. The TearLab Osmolarity System is intended to measure the osmolarity of human tears to aid in the diagnosis of patients with signs or symptoms of dry-eye disease, in conjunction with other methods of clinical evaluation. The 510(k) clearance allows the company to immediately begin market activities in the United States to clinical facilities categorized as high or moderate complex under the Clinical Laboratory Improvement Act of 1988 (CLIA ¡¯88).
¡°This 510(k) clearance is a significant milestone for our company and validates the performance of our TearLab Osmolarity System for use as an aid in the diagnosis of dry-eye disease,¡± said Eric Donsky, CEO of TearLab Corp. ¡°Given that DED is a continuum, it is critical to diagnose and treat patients early in disease progression. We hope the TearLab will change the practice paradigm for eye-care physicians in how they diagnose the DED patient population. The market for DED products is growing rapidly, and there are over 20 novel therapeutic compounds being developed for the treatment of DED. We are excited to participate in the expanding commercial opportunities in eye care.¡±
The TearLab Osmolarity System uses a lab-on-a-chip approach that requires less than 50 nanoliters of tear fluid in order to measure tear osmolarity. By using such a small amount of tears, the system eliminates the challenges that previously prevented point-of-care osmolarity testing, the company says. TearLab can produce a sample-to-answer result in less than 30 seconds and is simple enough to be operated by a technician, greatly improving patient throughput in the office setting.
Promising Results For Combo AMD Treatment
In late May, Ophthotech Corp. announced positive results of a Phase I clinical study evaluating E10030, its novel antiplatelet derived growth factor in conjunction with an antivascular endothelial growth factor, to treat wet age-related macular degeneration. Anti-PDGF therapy resulted in enhanced visual outcome and was associated with significant neovascular regression.
Fifty-nine percent of patients treated with anti-PDGF and anti-VEGF gained significant vision (three-line gain) at week 12 after therapy; 100 percent of treated patients demonstrated neovascular regression. E10030 was well-tolerated with no evidence of drug-related adverse events. Current standard of care treatment utilizing monotherapy anti-VEGF results in three-line visual gain in approximately one third of patients and without significant neovascular regression.
¡°Marked neovascular regression, a first in any study, with an outstanding level of visual gain, is very promising for our patients,¡± said Dr. Lawrence J. Singerman, clinical professor at
E10030 is an aptamer targeting PDGF, a key molecule involved in the recruitment and maturation of pericytes. Pericytes in neovascular tissue have been shown to be protective and play a major role in anti-VEGF treatment resistance. E10030 strips the pericytes from the neovascular tissue rendering it highly sensitive to an anti-VEGF attack.
Lacrisert Study Shows Quick Relief of Dry-Eye Symptoms
Aton Pharma announced results from a large (n=520) patient registry study of its Lacrisert insert (hydroxypropyl cellulose ophthalmic insert), a preservative-free, once-daily, sustained-release prescription insert indicated for moderate to severe dry eye.
The multicenter, two-visit, open-label, four-week study was conducted to determine both physician and patient acceptability and ease of use of Lacrisert in adult patients with a history of dry-eye syndrome. A patient registry study is designed to examine a wide range of correlations and show predictive relationships, providing a rich resource of data to mine over time. As reported by Bruce H. Koffler, MD, mean ocular surface disease index (OSDI) total scores for patients in the study significantly improved by more than 21 percent over the four weeks of the study; this was over and above any improvement patients may have gained from previous dry-eye therapies administered before the study.
