Expanded CD34+ cells/dorocubicel + unexpanded CD34– cells (Zemcelpro®) is indicated for the treatment of adult patients with haematological malignancies requiring allogeneic haematopoietic stem cell transplantation (allo-HSCT) after myeloablative conditioning for whom no other suitable donor cells are available. This cryopreserved allo-HSCT consists of two cell components derived from the same cord blood unit: CD34+ cells expanded ex-vivo using the UM171 molecule and unexpanded CD34– cells. The aim of this single intravenous infusion is to enable engraftment, immune reconstitution and an anti-tumour response. Zemcelpro® received conditional marketing authorisation from the European Commission in August 2025.

A pooled analysis of two multicentre, single-arm, open-label phase 2 studies investigated the efficacy and safety of Zemcelpro®. The efficacy analysis (n=25, median follow-up: 13.27 months) showed an overall survival rate of 66.0% at 12 months and 51.4% at 24 months. Progression-free survival was 52.8% at 12 months and 45.3% at 24 months. Non-relapse mortality was 21.2%. Median time to neutrophil engraftment was 20 days, and to platelet engraftment 40 days. Regarding safety (n=116, median follow-up: 22.49 months), nearly all patients (99.1%) experienced adverse events. The most common severe adverse events (grade ≥3) were lymphopenia (46.6%), anaemia (44.0%), neutropenia (35.3%), thrombocytopenia (31.9%), and acute graft-versus-host disease (22.4%). Acute graft versus host disease of any grade occurred in 66.4% of patients. Overall, 42 (36.2%) of patients died; of which 26 died due to disease progression or relapse (22.4%) and 15 due to treatment-related mortality (12.9%).

Zemcelpro® may represent a treatment option for patients lacking suitable donors in Austria, particularly for ethnic minorities with a lower probability of finding HLA-matched donors. However, there are currently no studies directly comparing Zemcelpro® with other therapies. Quality-of-life data and long-term data beyond 24 months are also lacking. Additionally, treatment with Zemcelpro® is associated with high costs (estimated additional costs of approximately €204,000 compared to unexpanded cord blood) and structural challenges related to international manufacturing and logistics.