Friday, September 26, 2014

Iluvien Update 8: Alimera Sciences Receives FDA Approval of Iluvien for Treatment of DME

After several attempts to gain approval for its NDA for Ilunien, the FDA has finally seen the light (after approval in the UK, Germany, and marketing or pending approvals in seventeen other EU countries).

I first began writing about Iluvien in July 2010 – see my comprehensive writeup about the technology behind this and other sustained delivery drug systems – Iluvien and the Future of Ophthalmic Drug Delivery Systems. In addition I have written about the products progress in seven updates, the latest in August 2012, Iluvien Update 7: Alimera Sciences to Re-File for FDA Approval of Iluvien for Chronic DME

Here are the statements from the two companies involved in bringing Iluvien to the market, Alimera Sciences, the marketing arm, and pSivida the licensor of the technology to Alimera:

Alimera Sciences announced that the U.S. Food and Drug Administration (FDA) has approved ILUVIEN for the treatment of diabetic macular edema (DME) in patients who have been previously treated with a course of corticosteroids and did not have a clinically significant rise in intraocular pressure (IOP). Alimera currently intends to begin selling ILUVIEN in the U.S. in the first quarter of 2015.

"We are very excited with this news from the FDA and thank the many people who contributed to this outcome and believed in ILUVIEN, including the retinal specialists, clinical site personnel, reading centers, and the many patients and their caregivers for helping us bring this long-term treatment to people in the U.S. with DME," said Dan Myers, president and chief executive officer of Alimera. "The approval of ILUVIEN under this broader label brings a DME treatment to the U.S. that lasts years, not months, after a single injection and greatly expands the addressable market opportunity in the U.S."

"The approval of ILUVIEN is wonderful news for the retinal community, as recent studies have indicated that as many as 50 percent of DME patients are not optimally managed with today's standard of care known as anti-VEGF therapies," said Pravin Dugel, M.D., Retinal Consultants of Arizona and clinical associate professor, Doheny Eye Institute, Keck School of Medicine, University of Southern California. "Having a multi-year delivery, low-dose corticosteroid drug will provide an additional treatment option for patients with this disease."

ILUVIEN (fluocinolone acetonide intravitreal implant) 0.19 mg is a sustained release intravitreal implant approved in the U.S. to treat diabetic macular edema (DME) in patients who have been previously treated with a course of corticosteroids and did not have a clinically significant rise in intraocular pressure. Each ILUVIEN implant is designed to release submicrogram levels of fluocinolone acetonide (FAc), a corticosteroid, for 36 months. The ILUVIEN approval was based on clinical trial data that showed that at month 24 after receiving the ILUVIEN implant, 28.7 percent of patients (p value .002) experienced an improvement from baseline in their best corrected visual acuity on the Early Treatment Diabetic Retinopathy Study (ETDRS) eye chart of 15 letters or more. Patients treated with ILUVIEN experienced a statistically significant improvement in visual acuity compared to the control group by week three of follow up, and maintained a statistically significant advantage over the control through completion of the trial at month 36.

"As the role of inflammation in DME becomes more clearly understood, the use of a continuous, long-term, low-dose anti-inflammatory, such as ILUVIEN, is an important option for patients who have DME that persists," said Barry Kuppermann, M.D., Ph.D., professor and chief of the Retina Service at University of California, Irvine.

"As the glaucoma specialist on the FAME Study Data Safety Monitoring Board, I have extensive familiarity with the IOP data related to ILUVIEN," said Richard Parrish, M.D., Professor and Director of the Glaucoma Service at the University of Miami Miller School of Medicine, Bascom Palmer Eye Institute.  "I am confident that the benefits of this important treatment for DME will outweigh concerns related to elevated IOP in the indicated patients."

And, from pSivida:

pSivida today announced that the U.S. Food and Drug Administration (FDA) has approved ILUVIENr for the treatment of diabetic macular edema (DME). It is indicated for patients who have been previously treated with a course of corticosteroids and did not have a clinically significant rise in intraocular pressure (IOP). A single injection of the ILUVIEN micro-insert provides sustained treatment of DME for 36 months. Approximately 560,000 people in the U.S. are estimated to have clinically significant DME, the most frequent cause of vision loss in individuals with diabetes and the leading cause of blindness in young and middle-aged adults in developed countries. ILUVIEN is expected to be commercially available in the U.S. in early 2015.

FDA approval of ILUVIEN entitles pSivida to a $25 million milestone from its licensee Alimera Sciences. pSivida will also be entitled to 20% of the net profits from sales of ILUVIEN in the U.S.

"FDA approval of ILUVIEN, our third FDA-approved product for retinal disease, provides an important treatment option for DME patients in the U.S., the majority of whose DME, despite anti-VEGF intra-ocular injections as frequently as monthly, is not optimally managed. ILUVIEN's clinical trials showed that ILUVIEN can actually reverse vision loss in many DME patients. Another advantage of ILUVIEN over existing therapies is that a single injection provides sustained therapy for three years," said Paul Ashton, Ph.D., president and chief executive officer of pSivida.

"The $25 million milestone will help finance our ongoing product development program, including MedidurT for posterior uveitis and TethadurT for the sustained delivery of biologics," added Dr. Ashton. pSivida is independently developing Medidur, an injectable, sustained release micro-insert of the same design and delivering the same drug as ILUVIEN, for the treatment of chronic posterior uveitis, the third largest cause of blindness in the U.S. The Company plans to seek FDA approval of this product on the basis of its ongoing single Phase III clinical trial. Enrollment of this study is expected to be completed by the end of the first quarter of calendar 2015.

ILUVIEN is already commercially available in the U.K. and Germany, and has received or is pending marketing approval in seventeen other EU countries, for the treatment of patients with the chronic DME insufficiently responsive to available therapies. "We are very pleased that the FDA's approval of ILUVIEN is not limited, as in the EU, to the subset of patients with chronic DME, patients who have failed other therapies, or patients who have had cataract surgery," continued Dr. Ashton.

ILUVIEN is an injectable micro-insert that provides sustained treatment through continuous delivery of a submicrogram dose of the corticosteroid fluocinolone acetonide for 36 months. Current standard-of-care therapy requires anti-VEGF injections into the eye as frequently as monthly, and studies show that over 50 percent of patients are not optimally managed with this treatment. FDA approval was based on clinical trial data that showed that at month 24, 28.7 percent of patients receiving ILUVIEN experienced an improvement from baseline in their best corrected visual acuity on the Early Treatment Diabetic Retinopathy Study (ETDRS) eye chart of 15 letters or more. This improvement in vision was maintained through 36 months, the end of the trials. 


Monday, September 15, 2014

Retina Revealed

Over the weekend, I read an excellent account of how the various parts of the retina work. Ben Shaberman, the senior science writer for the Eye on the Cure blog (Foundation Fighting Blindness), put together an easy to read and understand overview of what the various cell layers of the retina do and how they interact. Since the retina is the focus of most of what I write about, I asked Ben for his permission to reproduce the writeup in this space. Permission was granted and here is what he wrote:


By Ben Shaberman,  September 8, 2014
Eye on the Cure - Foundation Fighting Blindness

Your eyes are not just windows to your soul, but to your health as well. People rarely pay attention to their eyes, until something goes wrong. The eye is a delicate organ, and vision is a complex process involving various components.

Photoreceptors, in particular, get a lot of attention from researchers because they're the main cells in the retina that make vision possible. They convert light into electrical signals, which are sent to the brain and used to construct the images we see. Also, many retinal diseases begin with loss of photoreceptors.

However, the retina is like a multi-layer cake, with each layer comprised of different types of cells, all playing important roles in retinal health and vision. While preserving and restoring photoreceptors is often job number one for scientists, they also explore ways to protect other retinal cells from deterioration and even harness them to restore vision.

Here's a summary of the major retinal cell types, their functions and their potential roles in future treatments of diseases:


Choroid - The choroid is a layer of blood vessels that supplies oxygen and nourishment to the retina. Defects in the CHM gene cause choroideremia, a disease characterized by deterioration of the choroid, retinal pigment epithelium (RPE) and photoreceptors. In the wet form of age-related macular degeneration, leaky blood vessels expand from the choroid into the retina – a process called choroidal neovascularization – which causes loss of photoreceptors and central vision.

Retinal pigment epithelium - Also known as the RPE, this is a single layer of cells above the photoreceptors that provides them with essential nutrition and waste removal. In age-related macular degeneration (AMD) and Stargardt disease (SMD), toxic waste products accumulate in the RPE or between the RPE and photoreceptors. Subsequently, the RPE deteriorates, leading to loss of photoreceptors.

Photoreceptors -These are the retinal cells, known as rods and cones, that initiate the vision process by converting light into electrical signals. Rods provide low-light and peripheral vision. Cones are concentrated in the macula, the central region of the retina, and provide central and color vision. The outer segments of rods and cones are antenna-like projections that absorb light and convert it into electrical signals. Inner segments are the cell bodies where other supportive functions are performed. The adult human retina has approximately 125 million photoreceptors.

Bipolar cells - Their job is to receive electrical information on lighting intensity from photoreceptors and pass it along to other retinal cells. Bipolar cells often survive after photoreceptors are lost to disease. This makes them an attractive target for emerging optogenetic treatments, which are designed to provide light sensitivity and restore vision.

Ganglion cells - Ganglion cells receive input from many different cells in the inner retinal layers and process visual information, including detection of edges, contrast and colors. Ganglion cells extend to form an optic nerve, a million-fiber cable that conveys visual information from the eye to the brain. In people with advanced retinal disease, ganglion cells often survive longer than bipolar cells, making them a potential target for optogenetic therapies. Currently, scientists believe that bipolar cells may provide a more detailed visual experience than ganglion cells when treated with a light-sensing therapy, because they reside in layers of the retina closer to photoreceptors.

Muller glia - Muller cells extend through the retina, like spokes of a wheel, providing structural support and guiding light through the inner retina. They also transport molecules critical to retinal health and vision. Researchers believe Muller cells may even have the capacity to become new photoreceptors, which could lead to restoring vision. The research is still new, but success might someday have a big impact on the vision of people with advanced diseases.

A final note

The processing of visual information in the retina-beginning with 125 million photoreceptors and converging on a one-million-fiber optic nerve-remains a subject of intense research. There's still much that scientists don't know about the retinal cells and their roles. For example, little is known about the processing activities of amacrine and horizontal cells, which reside between bipolar and ganglion cells. However, advancing imaging technologies, including adaptive optics and optical coherence tomography, are helping complete the picture.

For additional information about retinal anatomy and function, please see the Eye on the Cure post "Appreciating the Beauty of the Retina." The University of Utah's Webvision is one of the best online sources for detailed information about the retina. I also want to thank John Flannery, Ph.D., at the University of California, Berkeley, for his editorial input.


Saturday, September 13, 2014

Stem Cells in Ophthalmology Update 26: First Wet AMD Patient Treated With RPE Derived from iPS Cells

Earlier this week, it was reported that Masayo Takahashi, an ophthalmologist at the RIKEN Center for Developmental Biology (CDB) in Kobe had appeared in front of a 19-member health-ministry committee for the safety of the clinical use of stem cells. She was flanked by Shinya Yamanaka, the biologist who first created iPS cells. Yamanaka shared the 2012 Nobel Prize in Physiology or Medicine for his breakthrough and now heads the Center for iPS Cell Research and Application in Kyoto. Takahashi was seeking approval to implant a retinal pigmented epithelial (RPE) sheet made from induced pluripotent stem (iPS) cells into a human patient.

Takahashi and her collaborators had shown in monkey and mice studies that iPS cells generated from the recipients' own cells did not provoke an immune reaction that causes them to be rejected. There had been concerns that iPS cells could cause tumours, but Takahashi's team found that to be unlikely in mice and monkeys.

To counter further fears that the process of producing iPS cells could cause dangerous mutations, Takahashi's team had performed additional tests of genetic stability. Guidelines covering the clinical use of stem cells require researchers to report safety testing on the cells before conducting transplants. The health ministry said that no problems were found and that the human trial could commence.

Only four days later (Friday, September 12th), the first patient was treated with the implanted sheet of RPE cells. She derived them from the patient's skin cells, after producing induced pluripotent stem (iPS) cells and then getting them to differentiate into retinal cells.

This is a major first for the stem cell and regenerative medicine fields.

Takahashi and her collaborators have been using induced pluripotent stem (iPS) cells to prepare a treatment for age-related macular degeneration. Unlike RPE derived from embryonic stem cells (i.e., as being done by Advanced Cell Technology), iPS cells are produced from adult cells, so they can be genetically tailored to each recipient. They are capable of becoming any cell type in the body, and have the potential to treat a wide range of diseases. The CDB trial will be the first opportunity for the technology to prove its clinical value.

A Japanese woman in her 70s is the world's first recipient of cells derived from induced pluripotent stem cells, a technology that has created great expectations since it could offer the same advantages as embryo-derived cells but without some of the controversial aspects and safety concerns.

In a two-hour procedure starting at 14:20 local time, a team of three eye specialists lead by Yasuo Kurimoto of the Kobe City Medical Center General Hospital, transplanted a 1.3 by 3.0 millimeter sheet of retinal pigment epithelium cells into an eye of the Hyogo prefecture resident, who suffers from age-related macular degeneration.

The procedure took place at the Institute of Biomedical Research and Innovation Hospital, next to the RIKEN Center for Developmental Biology (CDB) where ophthalmologist Masayo Takahashi had developed and tested the epithelium sheets.

Afterwards, the patient experienced no effusive bleeding or other serious problems, as reported by RIKEN.

Another important element to this story is that Japan has a clinical translation pipeline that is now faster with recent changes in regulations than that of the US. For example, this and future iPS cell-based transplants were approved as part of a clinical study, a type of clinical research mechanism that doesn't exist in the US. It is safe to say that the same technology with the same research team and outstanding level of funding would still be at least a few years away from their first patient in the US due to the different regulatory scheme.

As noted by Dr. Paul Knoepfler, in his writeup about the procedure:

 “The patient is clearly a brave hero. The team transplanted a huge (from a bioengineering perspective) 1.3 x 3.0 mm sheet of RPEs into the retina of the patient, who did not have any clear immediate side effects from the procedure. Keep in mind again that this sheet was made indirectly from the patients own skin cells so it is an autologous (or self) transplant, a notion that 10 years ago would have seemed entirely like sci-fi.”

“This is not only a huge milestone, but also an astonishingly fast translation of iPS cell technology from the bench to the bedside.”

 “Also, on the positive side we have the encouraging results from the ongoing clinical trials from Advanced Cell Technology (ACT) using a similar approach to macular degeneration, but employing human embryonic stem cells to make the RPEs.”

“For the vision impaired and the broader stem cell field, it is heartening to have two such capable teams working to cure blindness with pluripotent stem cells.”


Sources:



3. Stem cell landmark: patient receives first ever iPS cell-based transplant, Knoepfler Lab Stem Cell Blog, Paul Knoepfler, Septermber 12, 2014.