Benzinga | Jun 15, 2021 07:09AM EDT

Clearside Biomedical Announces Safety Results From Cohort 1 Of OASIS Phase 1/2a Clinical Trial Of CLS-AX In Wet AMD; Primary Endpints In Cohort 1 Were Achieved

- CLS-AX 0.03 mg dose delivered via suprachoroidal injection was well-tolerated with no treatment related adverse events -

- Initiating Cohort 2 patient screening for 0.1 mg dose in June 2021 -

ALPHARETTA, Ga., June 15, 2021 (GLOBE NEWSWIRE) -- Clearside Biomedical, Inc. (NASDAQ:CLSD), a biopharmaceutical company dedicated to developing and delivering treatments that restore and preserve vision for people with serious back of the eye diseases, announced today positive safety results from Cohort 1 of OASIS, its ongoing Phase 1/2a clinical trial of CLS-AX (axitinib injectable suspension) administered by suprachoroidal injection via Clearside's SCS Microinjector(r) in six patients (n=6) with neovascular age-related macular degeneration (wet AMD).

The primary endpoints were achieved in Cohort 1, as the initial lowest planned dose of 0.03 mg CLS-AX was well tolerated with no serious adverse events and no drug related treatment emergent adverse events observed throughout the study period. There were no signs of inflammation, no vasculitis, no intraocular pressure (IOP) safety signals, no dispersion of drug into the vitreous, or any other drug related adverse events observed in any of the patients. The OASIS Safety Monitoring Committee has reviewed the data and the trial will advance to Cohort 2. Clearside expects to begin Cohort 2 patient screening for a dose of 0.1 mg CLS-AX in June 2021 with completion of this four month study period expected by the end of the year.

"We are very encouraged by the Cohort 1 results of the OASIS trial and we are immediately beginning Cohort 2 enrollment as planned," said Thomas A. Ciulla, M.D., MBA, Chief Medical Officer and Chief Development Officer. "The initial data from Cohort 1 clearly achieved our safety and tolerability endpoints. While still early and recognizing there are a limited number of patients, we believe the Cohort 1 data supports our hypothesis that the combination of targeted and compartmentalized suprachoroidal delivery and the potent pan-VEGF attributes of axitinib may facilitate an effective treatment option for patients suffering from wet AMD."

The average age of the patients in Cohort 1 was 82 years and all were anti-VEGF treatment-experienced, having undergone numerous injections of standard-of-care anti-VEGF treatments prior to entering the OASIS trial. The mean number of prior anti-VEGF treatments within the twelve months and up to the 3 years prior to the start of the trial was 9.0 injections and 22.5 injections, respectively. All enrolled patients underwent diagnostic imaging at screening, followed by masked reading center confirmation of persistent active disease. The mean central subfield thickness (CST) of the macula was 231 ?m (range 208 - 294 ?m). The mean baseline best corrected visual acuity (BCVA) score as measured by Early Treatment Diabetic Retinopathy Study (ETDRS) letters, at the start of the trial was 59.0 (range 29 - 74).

As part of the trial design, at the initial visit, the six treatment-experienced patients in Cohort 1 received a standard-of-care, single intravitreal injection of 2 mg aflibercept. One month later, the mean ETDRS BCVA score for all patients remained stable, changing only by -0.2 letters, and patients then received a single suprachoroidal dose of 0.03 mg CLS-AX. One month after receiving CLS-AX, five of six patients exhibited improvement in BCVA, each gaining four or more letters, with mean ETDRS BCVA score of all patients increasing by +4.7 letters (p=0.029, post hoc, unadjusted). In Cohort 1: no patients required additional treatment with aflibercept at the one-month visit post CLS-AX; two patients went three months post CLS-AX without additional treatment with aflibercept and BCVA improved by 5 and 7 ETDRS letters for these patients; and four patients received additional treatment with aflibercept at the two month visit post CLS-AX. The mean CST was stable within 50 ?m for all Cohort 1 patients both at one month post 2 mg aflibercept and at one month post 0.03 mg CLS-AX.

"CLS-AX was well-tolerated and these initial results in this heavily treatment-experienced group of wet AMD patients are promising. I look forward to the continued clinical advancement of CLS-AX at the planned higher doses to further explore potential benefits in visual acuity, ocular anatomy and durability," added Mark R. Barakat, M.D., Director of Research, Retinal Consultants of Arizona; Clinical Assistant Professor, University of Arizona College of Medicine, Phoenix.

The current OASIS trial protocol includes a CLS-AX dose of 0.1 mg for Cohort 2 and 0.3 mg for Cohort 3, which equates to 3.3x and 10.0x the Cohort 1 dose of 0.03 mg. The Company expects to add a three-month extension study to follow patients in Cohort 2 and Cohort 3. Combined data from the multiple cohorts of the OASIS trial is planned to be presented at future medical meetings.

Information on Clearside's pipeline, including the CLS-AX program and Cohort 1 top-line results, are included in the Company's corporate presentation which may be accessed on the Clearside website under the Investors section: Events and Presentations.