With cash reserves dwindling, Oxurion plans early DME trial readout

Genetic testing hopes to speed up drug development in rare eye diseases

Oxurion will carry out an interim analysis of a phase 2 trial of its last remaining clinical asset – THR-149 for diabetic macular oedema (DME) – before the end of this year as it tries to get an early take on its efficacy.

With top-line results from the KALAHARI trial not due until the second half of 2023 – and cash reserves dwindling – the Belgian biotech hopes to look at the data after at least 25% of patients in the phase 2b portion of the study is completed.

Oxurion ended 2021 with €10 million in available cash, according to its annual report, and added to that total by raising another €10 million in a private placement that closed in March. The company was rocked in May by the failure of another candidate for DME in a phase 2 trial, forcing it to throw all its resources behind THR-149.

By the end of June, cash reserves had fallen to just over €3.7 million, and Oxurion indicated at that time that it did not have enough working capital for the following 12 months – a period which would come to an end before the KALAHARI readout.

That means it will have to raise additional funding or face the prospect of being unable to continue operations. A positive readout for THR-149 could make it easier to raise more capital from investors, or potentially license out the drug to another company.

THR-149 is a plasma kallikrein (PKal) inhibitor that Oxurion is hoping to position as a treatment for DME patients who do not respond to treatment with blockbuster anti-VEGF drugs like Bayer/Regeneron's Eylea (aflibercept) and Roche/Novartis' Lucentis (ranibizumab) – a group that represents up to 50% of all patients with the sight-robbing condition.

The KALAHARI trial has two parts, with the first dose-ranging stage showing that the drug was able to improve Best-Corrected Visual Acuity (BCVA) scores in patients who had failed to respond adequately to anti-VEGF therapy at the highest dose tested.

That dose – three monthly injections into the eye of 0.13 mg THR-149 – achieved a 6.1-point improvement in BCVA over baseline, which increased two 9 points if two patients who were considered be unsuitable candidates for treatment due to abnormalities were excluded.

Meanwhile, THR-149 was also able to stabilise central subfield thickness (CST) – which deteriorates in DME – for at least six months. The second stage of the study is comparing THR-149, Eylea, and a combination of the two drugs.

Last year, the Belgian company narrowed its focus to the two DME projects in order to conserve cash, halting investment in an oncology spinout – Oncurious – and putting some other R&D projects on hold.

The biotech is facing some big-name competition in DME, however, including from Roche, whose bispecific antibody Vabysmo (faricimab) targeting VEGF and Ang-2 was recently approved by the FDA.