Showing posts with label Glaucoma. Show all posts
Showing posts with label Glaucoma. Show all posts

Thursday, April 6, 2017

Key Details Regarding Glaucoma San Antonio


By Leslie Ball


There are a lot of problems that can develop within the eyes. People should do their best to care for this part of the body, especially as the body ages. Not many solutions are available when it comes to replacing sight or eyes. Glaucoma is a medical term used to describe a condition that causes optic nerve damage. Over time, it might worsen, particularly when it goes unaddressed. Glaucoma San Antonio services are an option for people living in or nearby the San Antonio TX region.

This condition is caused by a buildup of eye pressure. Glaucoma is typically an inherited condition that may not show up until a person is older. The increase of pressure is referred to as intraocular pressure. In time, t will damage the optic nerve, which is the part of the eye responsible for transmitting images to the brain. If this is damaged from the pressure, it could lead to permanent vision loss. Without treatment, blindness might take place within a couple of years.

Generally speaking, most people with this condition experience no symptoms or pain early on. This is why it is encouraged to have regular appointments with an eye doctor. If diagnosis is made early on, treatment can be offered and vision can be saved. People over age 40 with a history of this in their family should have full exams done every few years because they have increased risk of developing glaucoma. Those with diabetes are also more prone to this and other diseases.

It is important that people seek out the top professionals in their area. Compare the services offered, insurances accepted, fees and reviews and ratings. There are many health care providers who provide diagnostic care and treatment for people with glaucoma and other eye problems.

The two glaucoma types are open angle and angle closure. Open angle might also be called wide angle. This is the form seen most often. It occurs when the structures within an eye look normal but fluid in the eye is not flowing properly through the trabecular meshwork, which is the drain for eyes. With angle closure, also known as chronic or acute or narrow angle, poor drainage is the main issue. This is less common in western regions than in Asia. The issue with drainage is caused by the angle between the cornea and iris being too narrow and blocking the iris. The result is sudden buildup of eye pressure.

Few, if any, symptoms are experienced with this condition. The first official sign is often the loss of peripheral or side vision. This might go unnoticed for a long period, which is why glaucoma may be called the sneak thief of vision. Early detection is crucial for saving vision.

Intraocular pressure can rise to high levels. In these situations, people may notice halos around most lights, pain the eye, blurred vision and headaches. People are encouraged to seek medical attention promptly, if they notice eye pain, vomiting or nausea, loss of vision, halos, narrowing of visual field and redness in eyes.

There are many treatment options available. The type used on a patient might be based on his or her original condition. Some of the solutions that are used for managing glaucoma: microsurgery, eye drops and laser surgery. There are also certain medications that might be prescribed as part of treatment efforts.




About the Author:




Wednesday, January 11, 2017

A Potential Breakthrough in the Treatment of Glaucoma


Three related news items caught my attention last week. They had to do with the medical treatment of glaucoma.

The first item noted that patients don’t properly use their prescription eyedrops in treating elevated intraocular pressure (IOP). Dr. Ari Weitzer, writing in his Eye Doc News Blog, noted that a retrospective hospital study in a recent issue of the Archives of Ophthalmology said that after 1 year, only 22% of patients were adhering to their glaucoma treatment regimen and putting drops in their eyes – and this dropped to 11% after 3 years. It turned out that this was a study done in Singapore on an Asian population, but similar studies done in the U.S. show similar patterns.

So, compliance with putting drops in the eye is a major ongoing concern. In an editorial, also in the Archives of Ophthalmology, Drs. Kelly Muir and Paul Lee noted that many patients (only 31%) were able to correctly install a single eyedrop. Approximately 20% of patients depend on another person to install their eyedrops.

The second item that caught my attention was that the cost of glaucoma treatment drugs has gone up strongly over the past six years, with spending on glaucoma medications increasing 25% over the period 2001 to 2006. Part of this is due to a change to newer, more expensive medications such as the prostaglandin analogs, which are now the most prescribed and popular drugs in use, compared to older types like the beta blockers. Also, the prevalence of glaucoma is rising as the U.S. population ages (and people live longer). By 2020, it is estimated that 3.4 million people are expected to be affected. Currently, some 2.2 million Americans aged 40 or older have primary open angle glaucoma and the annual direct medical cost is estimated to be $2.8 billion.

But, the third item that caught my eye may be the saving grace. In a news release on June 14th, pSivida announced the commencement of a Phase I/II clinical trial to study a new bioerodible drug delivery implant for the treatment of glaucoma and hypertension. The implant is designed to provide long-term sustained release of latanoprost, one of the new class of prostaglandin analogs. The drug delivery implant, based on the company’s Durasert technology system, will be injected into the subconjunctival space in the eye (between the sclera and the lower lid), be bioerodible and is expected to deliver its drug for a period of months.

If successful, this implant would solve the problems of non-compliance, the inability to administer the drops and, depending on its price, perhaps address the increasing cost issues.

The new dose-escalating study is designed to assess the safety and efficacy of the implant in patients with elevated intraocular pressure and with hypertension. If successful, pSivida plans to advance the product into a multicenter Phase II study.

A Little Background Information

The Treatment of Glaucoma


I first wrote about glaucoma in the fall of 2001. At that time I prepared a comprehensive overview of what glaucoma is, how it is diagnosed/detected, and both the medical and surgical treatment options available or under development at that time. I even included some information on the U.S. market sizes for both treatment and equipment. To read this report, Advances in the Treatment of Glaucoma, published by OptiStock, please follow this link.

Sustained Release Drug Delivery Systems


I have also, more recently, written an extensive overview of ophthalmic drug delivery systems in my article titled, Iluvien and the Future of Ophthalmic Drug Delivery Systems. This report describes the development of Alimera Science’s Iluvien which delivers a corticosteroid (fluocinolone acetonide – FA) to the retina for treating macular edema for up to three years. It is based on a drug delivery system developed by pSivida and licensed to Alimera for this application.

The report also discusses both FDA-approved sustained delivery drug systems as well as those still in development. One of the systems mentioned as under development was a latanoprost coated punctal plug to treat open-angle glaucoma, that was being developed by QLT Therapeutics. It was supposed to stay implanted and deliver its drug for up to three months. Apparently, the plug did not stay in place well and did not demonstrate efficacy and, to my knowledge, is no longer being evaluated.

The pSivida Latanoprost Implant


Some Background Information

In their press release, pSivida stated that this was a joint development with Pfizer Inc. Pfizer and pSivida have been working together on drug delivery technology since 2007, with Pfizer investing in the company and helping to fund research and development.

According to the press release, the insert is being developed under the recently amended Research and Collaboration Agreement with Pfizer Inc. Under the revised agreement, Pfizer will make an initial payment of $2.3 million. pSivida will, with technical assistance from Pfizer, have the right to develop the glaucoma product candidate through Phase II clinical trials. At that point, Pfizer may exercise its option for an exclusive, worldwide license to develop and commercialize the product candidate in return for a $20 million payment, double-digit royalty payments on any sales of the product and additional development, regulatory and sales performance milestone payments of up to $146.5 million. If Pfizer does not exercise its option, pSivida will retain the right to develop and commercialize the glaucoma product on its own or with a partner. As part of the amended agreement, pSivida regains all rights to its intellectual property in ophthalmic applications previously included in the original Research and Collaboration Agreement other than that required for the latanoprost implant.

Latanoprost, which was approved for use in the eye in 1996,  is now off-patent and low-cost generic forms of the drug are available.

Officials from both companies commented on both the new agreement and on the proposed new application of the implant to treat glaucoma and hypertension:

"Pfizer is an excellent partner, and we are pleased to be entering into this new stage of our relationship involving development of a potentially enhanced glaucoma product," said Dr. Paul Ashton, President and CEO of pSivida. "The $2.3 million payment from Pfizer comes on top of the approximately $7.0 million in R&D support we have already received from Pfizer since we first started our partnership in 2007. We believe that regaining rights to intellectual property in the ophthalmic arena outside the scope of the amended agreement is a key step for our company."

Yvonne Greenstreet, Senior Vice President and Head of the Medicines Development Group for Pfizer's Specialty Care Business Unit, added, "Latanoprost is the most commonly prescribed drug for reduction of intraocular pressure in the treatment of ocular hypertension and glaucoma. If successfully developed and approved by regulatory authorities, using pSivida's unique drug-delivery technology to deliver latanoprost could play a significant role in addressing compliance issues associated with a daily eye drop regimen for the treatment of glaucoma."

The Technology: How the Implant Will Work

The Durasert latanoprost implant (see Figure 1), is a tiny translucent cylindrical polymer tube, between 3 to 4 mm in length and about 0.4 mm in diameter, that contains a small amount of latanoprost (supplied by Pfizer). It is about the size of a grain of rice, and is designed to provide a low daily dose of latanoprost, which has a good history of treating open-angle glaucoma and hypertension.

Figure 1. The pSivida Durasert latanaprost implant.      

The implant will be injected into the subconjunctival space of a patient's eye (between the sclera and the lower lid – see Figure 2) using a proprietary insertion device. The implant is bioerodible and is expected to deliver an appropriate dosage of latanoprost for about three months and, depending on the results of the Phase I/II dosing study, might last as long as six months. Since the implant is bioerodible, it will be absorbed by the eye and will not have to be surgically removed.

Figure 2. Illustration showing conjunctival space where implant will be placed.

Latanoprost, now off-patent and available in generic form, is one of the class of prostaglandin analogs which  reduce pressure in the eye by increasing the outward flow of fluid from the eye. They generally work by relaxing muscles in the eye’s interior structure to allow better outflow of fluids, thus reducing buildup of eye pressure. According to glaucoma specialists, the prostaglandins have taken the lead in recent years as a first-line therapy for treating open-angle glaucoma.

Side effects may include eye redness or irritation, a change in eye color (mostly in hazel or green eyes), increase in thickness and number or eyelashes, and joint aches or flu-like symptoms.

The Phase I/II dose-escalating study is currently underway at the University of Kentucky.