MediciNova has completed patient enrollment in a Phase 2 clinical trial evaluating MN-166, also known as ibudilast, for the prevention of chemotherapy-induced peripheral neuropathy in patients with metastatic colorectal cancer.

The randomised, placebo-controlled study, known as Oxtox, has enrolled 100 patients across 11 clinical sites in Australia. Recruitment is now closed, with participants continuing chemotherapy alongside either MN-166 or placebo until disease progression or unacceptable side effects.

Chemotherapy-induced peripheral neuropathy is a common and often dose-limiting complication of widely used cancer treatments, including oxaliplatin. Symptoms such as numbness, tingling and pain can persist long after treatment has ended, affecting quality of life and, in some cases, forcing dose reductions or early discontinuation of chemotherapy.

The Oxtox study is an investigator-initiated trial led by Dr Janette Vardy and Dr Haryana Dhillon and focuses on patients receiving oxaliplatin-based chemotherapy for metastatic colorectal cancer. Patients were randomised across two treatment arms and will be followed until six months after completion of chemotherapy. While the exact study completion date has not been confirmed, MediciNova expects top-line data to be available in 2026.

MN-166 is a small molecule inhibitor of phosphodiesterase type-4 and inflammatory cytokines, including macrophage migration inhibitory factor. The compound has been investigated across a range of neurological and inflammatory conditions, reflecting growing interest in its potential neuroprotective and anti-inflammatory properties.

In addition to chemotherapy-induced peripheral neuropathy, MN-166 is in late-stage clinical development for neurodegenerative diseases including amyotrophic lateral sclerosis and progressive multiple sclerosis, as well as degenerative cervical myelopathy. The compound is also being explored in glioblastoma, Long Covid, substance use disorder and acute respiratory distress syndrome.

For amyotrophic lateral sclerosis, MN-166 has received orphan drug designation and fast track status from the US FDA, as well as orphan drug designation from the European Medicines Agency. These regulatory designations are intended to support the development of treatments for conditions with high unmet medical need.

The completion of enrollment in the Oxtox study comes amid increased focus on supportive oncology care, particularly interventions designed to reduce treatment-related toxicities rather than directly target tumours. Effective prevention strategies for chemotherapy-induced peripheral neuropathy remain limited, and there are currently no approved therapies specifically indicated to prevent the condition.

If successful, the Oxtox study could help clarify whether targeting inflammatory pathways with ibudilast can reduce the incidence or severity of neuropathy in patients receiving oxaliplatin, potentially allowing patients to remain on optimal chemotherapy dosing for longer.

MediciNova said the study’s progress represents an important step in evaluating MN-166’s role beyond disease-modifying therapies and into supportive cancer care, where quality-of-life considerations play a critical role in treatment decision-making.

Results from the trial are expected to inform future development plans for MN-166 in oncology settings, including whether larger, later-stage studies are warranted.