COVID-19 can’t stop the American Society of Retina Specialists (ASRS)! Although their meeting needed to be held online this year thanks to the viral pandemic, the ASRS recently ran a successful 2020 Virtual Annual Meeting. During this time, professionals, practitioners, and companies alike discussed various ophthalmologic topics, ranging from research to treatment. Biopharmaceutical company Clearside Biomedical announced that the company made multiple presentations during the meeting regarding its pipeline and proprietary tools. Check out copies of the presentations on their website.
Clearside Biomedical: The Presentations
Clearside Biomedical shares a positive mission: to discover treatments to save vision in patients with eye diseases. This year, at the ASRS 2020 Virtual Annual Meeting, the company presented on the following topics:
CLS-AX
Also known as axitinib injectable suspension, CLS-AX acts as a VEGF-inhibitor. Vascular endothelial growth factor (VEGF) plays a role in blood vessel growth. However, in many eye diseases, blood vessels become weak or leaky. As a result, VEGF inhibitors stop the growth of blood vessels, preserving vision and protecting the eye. Currently, Clearside Biomedical is developing CLS-AX as a treatment for wet macular degeneration (wet AMD).
During ASRS 2020, authors David Brown, Thomas A. Ciulla, and Viral Kansara discussed the tolerability, safety, and efficacy of CLS-AX for patients with wet age-related macular degeneration. Their study did not use human patients, but rather animal models of eye disease. In addition to its high tolerability, researchers saw prolonged benefits in symptom reduction and vision clarity. As a result, the authors believe that CLS-AX is a potentially beneficial bi-annual treatment for patients with the disease.
Macular Edema
According to the ASRS:
Macular edema refers to an abnormal blister of fluid in the layers of the macula. [It is] typically caused by increased leakage from damaged retinal blood vessels or growth of abnormal blood vessels in the deep retina [and makes] it more difficult to see clearly.
While macular edema is not a disease, it is usually a symptom of one. For this topic, Clearside Biomedical offered two presentations. In the first, by Thomas A. Ciulla, he explored the intersection of macular edema and retinal vein occlusion. Even when treated with VEGF inhibitors, patients with retinal vein occlusion and macular edema experienced worse vision and overall outcomes than patients in randomized clinical trials. This suggests that anti-VEGF treatments may not be effective for patients with this condition.
In the secondary presentation, from Thomas A. Ciulla and Michael Ip, they discussed the relationship between best corrected visual acuity and central subfield thickness in patients with macular edema. Best corrected visual acuity (BVCA) is described by the Manhattan Lasik Center as:
Measurement of the best vision correction that can be achieved, such as glasses, as measured on the standard Snellen eye chart. For example, if your uncorrected eyesight is 20/200, but you can see 20/20 with glasses, your BCVA is 20/20.
Central subfield thickness, on the other hand, refers to macular thickness. Researchers discovered that there is some correlation between BVCA and macular thickness. Next, researchers will use this knowledge to understand how to develop better diagnostic tools, make better clinical decisions, and more properly treat patients.
Suprachoroidal Delivery
Basically, suprachoroidal delivery means administering a therapy to a portion of the eye between the sclera and the choroid. Clearside Biomedical does this through their Suprachoroidal Space (SCS) Injection Platform, a patented treatment approach to effectively deliver therapies to the portion of the eye where disease begins. For this topic, three separate presentations were made.
First, Steven Yeh, Thomas A. Ciulla, and Viral Kansara discussed how suprachoroidal injections of triamcinolone acetonide, complement inhibitor, and tyrosine kinase inhibitor improved patient outcomes and promoted vision without adverse reactions. According to the researchers, these therapies caused similar patient outcomes too steroids. However, they acknowledge that more research is needed.
Next, Christopher R. Henry, Cherry Wan, and Barry Kapik analyzed the largest aggregate dataset regarding suprachoroidal injections to determine consistency, reliability, safety, and efficacy. They found that the procedure is most effective when doctors are given a choice between two needle lengths. This allows patients with different diseases, disease progressions, and anatomy to all be treated. Additionally, researchers found a connection between needle length and biological sex.
Finally, Shree Kurup, Cherry Wan, and Barry Kapik performed another analysis of suprachoroidal injections for patients with uveitis. Once again, they found that two needles were needed for anatomical differences. However, they also discovered that in additional to biological sex, needle length also correlated with age and area of injection.
Macular Edema with Uveitis
In the final set of presentations, which discussed macular edema in relation to uveitis, researchers discussed PEACHTREE clinical trial findings. The first presentation, from Quan Dong Nguyen, found that suprachoroidal injections greatly improved both vision and macular degeneration in patients with uveitis. Nearly half of all participants gained a significant improvement in vision.
According to Ashvini Reddy and Thomas A. Ciulla, their own findings were similar. PEACHTREE showed the benefit of treating uveitis and macular edema with CLS-TA, regardless of prior treatment.
