Clinical Trials Arena

Enlivex advances lead cell therapy to Phase IIb in osteoarthritis

The novel cell therapy significantly improved knee function, pain and stiffness in certain patients with primary knee osteoarthritis.

Enlivex Therapeutics is planning to advance its lead cell therapy asset, Allocetra, to Phase IIb trials following the positive results from the primary group of its Phase I/IIa study in knee osteoarthritis (KOA).

Though the resident macrophage-targeting therapy failed to have a statistically significant impact on the study’s entire patient population, three biweekly doses of the drug were shown to statistically reduce Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores associated with knee pain, function and stiffness in a primary osteoarthritis (POA) population.

During the ENX-CL-05-001 (NCT06233474) study, the POA group – which is categorised by disease onset due to ageing and general joint wear and tear – experienced a 72% reduction in WOMAC knee pain scores compared to placebo, while function scores increased by 95%. Both figures were statistically significant, with p values of 0.03 and 0.007, respectively.

Allocetra also significantly improved WOMAC stiffness and function change, as well as pain and function change scores – boosting these by 47% and 49%, respectively.

Following the positive results of the Phase I/IIa trial, Enlivex plans to obtain regulatory approval from the US Food and Drug Administration (FDA) for a Phase IIb trial of Allocetra, which the company estimates will come by Q2 of 2026.

According to this timeline, the biopharma expects to dose the first patient in this trial by Q3 of 2026.

These results come at a time when there is a strong unmet need for patients with KOA, as the non-surgical current treatment landscape revolves around the use of steroids and non-steroidal anti-inflammatory drugs (NSAIDs) like naproxen and ibuprofen.

Though there are limited treatment options available for patients, the osteoarthritis market was worth $2.5 billion in 2021, according to a report by the parent company of Clinical Trials Arena, GlobalData.

However, to be successful in this indication, Allocetra may have to fend off competition from other drug candidates moving forward, as there are currently 30 ongoing Phase III clinical trials assessing the efficacy of biologic drugs for osteoarthritis.

This includes R-Biopharm’s autologous stem cell therapy, JointStem, which was granted Breakthrough Therapy designation by the US Food and Drug Administration (FDA) in March 2025.