Opthea discontinues COAST and ShORe sozinibercept combination therapy trials

Opthea is assessing its rights and obligations under its Development Funding Agreement with investors and other stakeholders. Image credit: ©natali_mis – stock.adobe.com

Opthea has made the decision to discontinue its COAST and ShORe trials in wet age-related macular degeneration (AMD) following the announcement that the COAST trial failed to meet its primary endpoint.

In addition to announcing the termination of ShORe, the company also accelerated topline results from the trial showing that it, too, failed to meet its primary endpoint of mean change in best corrected visual acuity (BCVA) from baseline to week 52. The global ShORe phase 3 trial evaluated the efficacy and safety of intravitreally administered 2 mg sozinibercept every 4 or 8 weeks in combination with 0.5 mg ranibizumab every 4 weeks, as per label, versus 0.5 mg ranibizumab monotherapy.

Results from the trial showed that participants receiving sozinibercept combination therapy with a dosing regimen of every 4 weeks (n=301) or every 8 weeks (n=301) achieved a mean change in BCVA of 13.3 or 12.9 letters from baseline to week 52, respectively, versus 14.2 letters with ranibizumab monotherapy (n=299, P-values of 0.35 and 0.19, respectively). In the overall population, participants receiving sozinibercept combination therapy with a dosing regimen of every 4 weeks (n=328) or every 8 weeks (n=326) achieved a mean change in BCVA of 13.3 and 12.6 letters from baseline to week 52, respectively, versus 14.3 letters with ranibizumab monotherapy (n=331; P-values of 0.32 and 0.09, respectively).

Frederic Guerard, PharmD, CEO of Opthea, commented on the decision to discontinue the trials in a press release from the company.

“We are disappointed that COAST and ShORe did not demonstrate the improvements in vision with sozinibercept combination therapy compared to standard of care that we had hoped for,” said Guerard. “We are grateful to all patients, clinical investigators and their staff around the world who participated in the sozinibercept Phase 3 clinical program, and for their contributions in investigating new treatments for wet AMD.”

As previously reported, Opthea has been assessing its rights and obligations under its Development Funding Agreement (DFA) with the investors under the DFA, among others. The company updated this by saying Opthea and DFA Investors agreed to discontinue the development of sozinibercept in wet AMD with immediate effect, and that this decision did not constitute a termination event under the DFA resulting in any amount payable by Opthea. A termination event would cause Opthea to pay investors up to four times the amounts paid to the company under the DFA.

The company did note, however, that it remains possible under the DFA, in certain circumstances upon or following termination of the DFA, Opthea could become required to pay a multiple of the amount funded by the DFA Investors that would have a “material adverse impact on the solvency of the company.” Termination can be triggered by a range of events including Opthea’s insolvency, in which case Opthea will be obligated to pay a multiple of the amounts funded by the DFA Investors.

The company noted that it is currently relying on the "safe harbour" provisions in section 588GA of the Corporations Act 2001 (Cth) and that trading in Opthea’s listed securities will be suspended by ASX under ASX Listing Rule 17.3 until the company is in a position to provide an announcement to the market providing more clarity on these issues and the impact on its financial position.

References:

1. Opthea announces decision to discontinue wet AMD trials. News release. Opthea. Published March 31, 2025. Accessed March 31, 2025. https://ir.opthea.com/news-releases/news-release-details/opthea-announces-decision-discontinue-wet-amd-trials-0

2. Harp M. Opthea phase 3 clinical trial, COAST, in patients with wet age-related macular degeneration fails to meet primary endpoint. Ophthalmology Times. Published March 24, 2025. Accessed March 31, 2025. https://www.ophthalmologytimes.com/view/opthea-phase-3-clinical-trial-coast-in-patients-with-wet-age-related-macular-degeneration-fails-to-meet-primary-endpoint