An emerging technique using microscopic needles to deliver drugs to the eyes could revolutionize the treatment of common vision-threatening diseases.
Researchers from the Georgia Institute of Technology and Emory University (GA, USA) have been investigating minimally invasive drug delivery to the eye using microneedles. The needles penetrate eye tissue less than traditional needles (only as deep as 0.5 mm), resulting in less damage to the eye than traditional techniques. Furthermore, patients need only be under local anesthetic to receive treatment with the microscopic needles.
Drug delivery to the eyes is a complicated matter. Eye drops suffer from an inability to ensure that consistent, correct levels of drug reach the back of the eye, whereas traditional injections are invasive, penetrating across eye tissues.
“Although the research is at an early stage it does show that it is possible to use microneedles to effectively deliver drugs to targeted sections of the eye, such as the anterior and posterior portions. No inflammatory response or other adverse effects were observed in our early tests. This is promising news for those who are suffering from vision-threatening diseases, such as glaucoma, macular degeneration and diabetic retinopathy,” commented Samirkumar Patel, a member of the research team.
While the preliminary results, which were presented at the Ophthalmic Drug Delivery Symposium (UK), are promising, further research is necessary to confirm the needles’ safety and to increase our understanding of the long-term effects of this method of drug delivery.
Source: The Royal Pharmaceutical Society of Great Britain www.rpsgb.org/pdfs/pr080630.pdf.
Durezol™ receives US FDA approval for the treatment of postoperative ocular pain and inflammation
Drug: Difluprednate ophthalmic emulsion
Tradename: Durezol™ 0.05%
Manufacturer: Sirion Therapeutics
Indication: Treatment of ocular postoperative inflammation and pain
In the USA, more than 5 million ophthalmic surgeries are performed yearly. After surgery, many patients experience pain and inflammation, which, if left untreated, can result in impaired visual rehabilitation or further complications. Current treatment options include corticosteroids and NSAIDs. As Michael Korenfeld, (Washington University, St. Louis, MO, USA) commented, “Rapid resolution of inflammation and pain is very important following ocular surgery.”
Following a 6-month priority review of data from two multicenter Phase III trials conducted in the USA, Sirion Therapeutics has US FDA approval for Durezol™, a topical steroid for reducing postoperative ocular inflammation and pain. The efficacy of Durezol was compared with placebo applied either twice or four-times daily. In total, 438 patients who presented with significant inflammation 1 day after surgery were included in the studies. Both regimens resulted in decreased anterior chamber cells 2 weeks postsurgery, with similar efficacy between the two Durezol groups (86 vs 87% for two- and four-times daily administration, respectively). The strong desire for aggressive treatment of inflammation, coupled with the slight observed benefit over the twice-daily regimen, led the four-times a day regimen to be recommended to doctors.
While IOP remained within normal ranges for all study groups throughout the trial, 3% of patients in each of the Durezol-treated groups and 1% of those in the placebo group experienced a clinically significant rise in IOP (an observed value of 21 mmHg or more and an increase from baseline of 10 mmHg). Overall, treatment with Durezol was well tolerated, with few adverse events.
“Durezol … is a potent topical steroid that works rapidly and effectively to resolve postoperative inflammation and pain,” said Barry Butler, President and CEO of Sirion Therapeutics, Inc. “We believe that having access to a steroid that treats both inflammation and pain gives physicians a more complete treatment approach.”
Source: Sirion Therapeutics www.siriontherapeutics.com.
Diabetes medication may slow retina disease progression
Study finds diabetic patients taking rosiglitazone may be less likely to develop proliferative diabetic retinopathy or reductions in visual acuity.
Researchers from the Jules Stein Eye Institute (CA, USA) analyzed the medical records of diabetic patients treated at the Joslin Diabetes Center (MA, USA) in 2002–2003. The records of 124 patients receiving rosiglitazone treatment were compared with 158 patients not receiving rosiglitazone or a similar medication. Results showed that those receiving treatment had a lower risk of proliferative diabetic retinopathy than those receiving no such treatment.
When the study began, 14 eyes in the rosiglitazone group and 24 eyes in the control group had severe nonproliferative diabetic retinopathy. Of these, after 1 year, 7.7% of eyes in the rosiglitazone group and 29.2% of those in the control group had progressed to proliferative diabetic retinopathy. At 3 years from study initiation, these levels increased to 19.2 and 47.4% in the rosiglitazone and control groups, respectively, yielding a relative risk reduction of 59.5% afforded by rosiglitazone treatment. The researchers also considered visual acuity loss in their review and found that fewer eyes in the rosiglitazone group experienced a loss of three or more lines on the vision chart (average follow-up: 2.8 years).
While these result suggest that rosiglitazone treatment may slow diabetic-associated ophthalmic disorders, the authors caution against administering the drug to diabetes patients for this reason: “Because this study does not rigorously prove that rosiglitazone either reduces the incidence of proliferative diabetic retinopathy or prevents loss of visual acuity … rosiglitazone treatment of patients with diabetes specifically to reduce these ophthalmic complications is not advocated at this time.”
In addition, potential adverse effects of treatment with the drug must be acknowledged. These include fluid build-up, abnormal liver function test and worsening of congestive heart failure. Further investigation is necessary to definitively determine the benefits, and potential risks, of rosiglitazone in the treatment of diabetic proliferative retinopathy.
Source: Shen LQ, Child A, Weber GM, Folkman J, Aiello LP. Rosiglitazone and delayed onset of proliferative diabetic retinopathy. Arch. Ophthalmol. 126(6), 793–799 (2008).
New software allows blind people to browse the internet from any computer
Recently launched software, WebAnywhere, makes screen reading available as an internet service, allowing blind people to surf the internet from any computer, for example in a library, school or hotel.
Looking ahead to future trends in computer use, many recognize that we are moving away from using primarily one desktop computer and towards using multiple computers, depending on our location and needs. Many people now store increasing amounts of information, such as email, on the internet. However, this poses challenges for those who are blind or visually impaired, as screen-reading software is generally only installed on their own computers. Unlike other free screen-reading programs, WebAnywhere does not have to be downloaded onto a computer to be used. The software is web hosted and processes text on an external server, before sending an audio file to play in the user’s web browser.
“This is for situations where someone who’s blind can’t use their own computer but still wants access to the internet. At a museum, at a library, at a public kiosk, at a friend’s house, at the airport,” said Richard Ladner (University of Washington, WA, USA).
The developers have tested the software over a number of months, asking people to test common uses of the internet on public computers, including checking email, checking transport timetables and searching for a restaurant phone number. The software enabled people to successfully complete these tasks using a range of machines and different internet connections.
The fact that the program is hosted on the internet, meaning that each time the software is used, users can be sure of having access to the most up-to-date version, is particularly attractive to many.
Following its recent launch, WebAnywhere developer Jeffrey Bigham (University of Washington) is already planning updates and additions to the current software, increasing web accessibility further for the blind and visually impaired. “Traditional desktop tools such as email, word processors and spreadsheets are moving to the Web,” Bigham commented. “Access technology, which currently runs only on the desktop, needs to follow suit.”
Source: University of Washington News http://uwnews.org; http://webanywhere.cs.washington.edu.
Study suggests uveitis flares in ankylosing spondylitis are reduced by adalimumab
Data presented at the European League Against Rheumatism show that adalimumab reduces the frequency of anterior uveitis flares in ankylosing spondylitis patients.
Ankylosing spondylitis is a rheumatic disease affecting approximately 80,000 people in the UK, occurring most commonly between the ages of 15 and 35 years. Approximately 30–40% of patients with ankylosing spondylitis will experience inflammation of the eye connected to their disease. Symptoms generally include redness, pain, sensitivity to light and skewed vision. Patients experiencing such symptoms are encouraged to visit their physicians promptly to allow swift treatment, usually with corticosteroid and dilating-agent eye drops.
As well as specific exercises designed to maintain mobility and reduce spine curvature, treatment for ankylosing spondylitis often includes anti-inflammatory drugs (e.g., aspirin, ibuprofen, indometacin, naproxen and COX-2 inhibitors), disease-modifying antirheumatic drugs (such as ciclosporin, methotrexate, sulfasalazine and corticosteroids) and TNFα blockers (e.g., etanercept, infliximab and adalimumab). The TNFα blockers are promising agents, slowing disease progression in many patients. Researchers from Charité – University Medicine Berlin (Germany) examined whether the TNFα blocker adalimumab had any effect on the frequency of uveitis flares in ankylosing spondylitis patients.
In total, 1250 patients with active ankylosing spondylitis (Bath disease activity index ≥ 4) were included in the open-label study. Treatment administered during the study was intended to be representative of standard clinical care. Patients had all received prior treatment with at least one NSAID and received subcutaneous adalimumab 40 g every other week for 12 weeks; the mean length of treatment was 106 days.
From the whole study population, 25 patients (2%) reported 27 anterior uveitis flares. Of the 274 patients with a history of anterior uveitis, 23 patients (8%) reported 25 flares. A subset of these patients had chronic uveitis (n = 43); ten flares were experienced in this group. New-onset uveitis occurred in two patients. Analysis of the results demonstrated that adalimumab therapy was associated with a significant reduction in anterior uveitis flares.
While a previous study has shown that the TNF antagonists as a class reduce the rate of uveitis flares in this patient population, this is the first study to specifically evaluate the efficacy of adalimumab in this regard. The researchers are confident that the results demonstrate that adalimumab is effective at reducing anterior uveitis flare frequency in patients with ankylosing spondylitis.
Source: Rudwaleit M, Rødevand E, Holck P et al. Adalimumab (Humira®) inhibits uveitis flares in patients with ankylosing spondylitis (AS). (Abstract SAT0261) www.eular.org/congress_08_home.cfm.