Another Oxurion eye disease drug flunks phase 2, leaving biotech all-in on last prospect

Oxurion is left with one last shot at success. The latest drug candidate to flounder in the clinic is THR-687, a pan RGD integrin antagonist that failed a midphase eye disease trial, dragging Oxurion’s stock down 40% to 0.60 euro cents ($0.63).

Belgium-based Oxurion went into 2019 focused on three candidates. Anti-PlGF antibody THR-317 failed a phase 2a clinical trial in diabetic macular edema (DME) later that year, leading Oxurion to drop the asset but brush off the setback by pointing to the promise of its two remaining candidates. Oxurion said the retinal disease community was already more interested in the two earlier-stage prospects than it ever was in THR-317.

Now, one of those two prospects has underwhelmed in the clinic. Part A of the phase 2 clinical trial administered one of two doses of THR-687 in three monthly injections into the space at the back of the eyes of treatment-naïve DME patients. The safety and efficacy analyses featured 16 and 14 participants, respectively. 

Because of the Part A data, the study will never advance to Part B. Oxurion saw “insufficient evidence of efficacy on the key endpoints,” namely the best-corrected visual acuity vision test and a measure of macular thickness. The biotech is yet to share the data but was sufficiently unimpressed to opt against taking THR-687 forward. Oxurion will look into potential partnerships for the asset. 

The action, coupled with Oxurion’s earlier decision to stop investing in its oncology spinout, means the biotech is now all-in on its plasma kallikrein inhibitor THR-149. The candidate, which is aimed at the 50% of patients who suboptimally respond to the current standard of care, is in the second part of a phase 2 DME trial that is scheduled to deliver data around the middle of next year.

Oxurion ended last year with 10 million euros and raised a similar amount in a private equity placement in February 2022. After seeing THR-687 fail, the biotech has embarked on a “thorough review of our capital and resource allocation plans to ensure that they are aligned with our objective of maximizing value creation for all stakeholders,” Oxurion CEO Tom Graney said in a statement.