Cloudbreak Pharma said its phase 3 trial of CBT-001 in pterygium hit both co-primary endpoints, delivering a clinical win for a company still dealing with an investigation into whether its IPO created an artificial impression of demand for its stock.
The update matters because pterygium lacks FDA-approved therapies, giving Cloudbreak a chance to define a treatment category if the data hold up in fuller disclosure and in the program’s next regulatory steps. It also gives investors a clearer view of the asset at a time when trading in the company’s shares has been suspended in Hong Kong since September.
The data
Cloudbreak is developing CBT-001 as a multi-kinase inhibitor eye drop for pterygium, an ocular surface disease. In the phase 3 study, patients received either dose of CBT-001 twice daily for three months.
According to the company, both doses produced statistically significant improvements versus placebo on conjunctival hyperemia, meeting one co-primary endpoint. Cloudbreak said redness in the white of the eye improved starting from Week 2 and that the effect was maintained at every visit through Month 12.
The second co-primary endpoint assessed the effect of CBT-001 on pterygium lesion length through Month 12. Cloudbreak said both doses again beat placebo. The company has not yet released detailed data, but said the treatment-versus-vehicle benefit was about 10% of baseline and had not yet plateaued at Month 12.
On safety, superficial punctate keratitis was the most common adverse event on CBT-001. It affected 20% of patients on the low dose, compared with 8% on placebo. Cloudbreak said most cases resolved after treatment with artificial tears, and reported a similar adverse event profile for the high dose, although at a higher incidence.
The road here
Cloudbreak said it plans to meet with the FDA to review the findings and discuss potential next steps. In March, the company said it planned to start a second phase 3 trial in the third quarter of 2026 and complete that study in late 2028. In September, it estimated U.S. commercialization of CBT-001 between 2030 and 2032.
The commercial setup is already partly regional. Cloudbreak has a commercialization partnership for Greater China and another deal covering Asian markets including Japan and South Korea. As of March, the biotech was exploring self-commercialization and outlicensing options for the U.S. and other regions.
That development progress is unfolding while the company manages corporate scrutiny. In late September, Cloudbreak said its board had formed an independent special committee to investigate concerns about its IPO, and the company delayed its 2026 interim report in response to the internal investigation. The phase 3 result does not resolve those issues, but it does give Cloudbreak a tangible operating milestone while the broader corporate process remains unsettled.
