Navidea Biopharma is dropping its rheumatoid arthritis (RA) programme after announcing disappointing results from an exploratory analysis of the NAV3-33 trial.
The Phase III study (NCT05246280), which enrolled 523 patients, aimed to confirm the ability of intravenous (IV) Lymphoseek (Tc 99m tilmanocept) imaging to predict clinical response in individuals with RA who are beginning anti-tumour necrosis factor alpha (TNFα) therapy.
The exploratory analysis sought to optimise the diagnostic performance in support of the methodologies for a final pivotal trial. While the results confirmed that IV Lymphoseek can reliably image macrophage activity in RA patients, the images cannot predict which patients will respond to treatment with an anti-TNFα medication.
On the results of the exploratory analysis, Navidea’s CEO Michael Blue said: “We were very surprised and disappointed that the results of the exploratory analysis did not support the hypothesis of an overall accuracy of early treatment response approaching 90%, but rather, the overall accuracy of early treatment response was on average consistently below 70%.”
Following these results, Navidea has said it is suspending all activities related to the RA trial. The company will now focus on exploring all opportunities related to its therapeutic assets, as per the 3 July press release.
RA is an autoimmune disorder causing chronic inflammation of the joints. Anti-TNFα therapies involve using biologic drugs to inhibit TNFα, a cytokine that promotes inflammation in RA, thereby reducing joint inflammation, pain, and damage. There are several anti-TNFα drugs approved for use in RA including Amgen’s Enbrel (etanercept) and Johnson & Johnson’s Remicade (infliximab).
Lymphoseek – which is US Food and Drug Administration (FDA)-approved for lymphatic mapping in patients with solid tumours – is a radiopharmaceutical agent designed to identify sentinel lymph nodes that may be involved in metastasis in patients with breast cancer, melanoma, and head and neck cancers.
In 2016, Cardinal Health acquired rights to Lymphoseek from Navidea in North America. Navidea received $80m at closing, plus the opportunity to earn up to $230m based on certain milestones through 2026. In 2021, the diagnostic agent received expanded FDA approval for use in paediatric patients with melanoma, rhabdomyosarcoma (RMS), and other solid tumours.
It has been a rocky few years for Navidea. In January 2024, the company filed a Form 15 with the Securities and Exchange Commission (SEC). According to the company, its decision to proceed with the deregistration was aimed at “further reducing the complexity and costs of reporting following the recent delisting of Navidea from the NYSE American LLC”. The board of directors at the NYSE agreed with the decision to start removing the company’s stock from the exchange in October 2023.
