Zemcelpro: A New Hope for Blood Cancer Patients Needing Stem Cell Transplants

On June 20, 2025, the European Medicines Agency (EMA) recommended granting a conditional marketing authorization for Zemcelpro (dorocubicel), a groundbreaking therapy aimed at treating adults suffering from hematological malignancies—commonly known as blood cancers. This innovative treatment provides a viable option for patients who require an allogeneic hematopoietic stem cell transplantation (allo-HSCT) but have no suitable donor available.

Hematological malignancies encompass a range of blood cell cancers, including leukemias, lymphomas, myelodysplastic syndromes, and myelomas. These cancers are among the most frequently diagnosed malignancies, and allo-HSCT represents the only curative treatment available for many patients. The process involves the transplantation of stem cells from a donor, which replaces the recipient's bone marrow cells with healthy ones capable of producing normal blood cells.

Zemcelpro enhances the effectiveness of umbilical cord blood stem cells, which are often used in transplants when no matched donor is available. This therapy specifically addresses the limitation of low stem cell counts typically found in umbilical cord blood units, which can delay engraftment—the successful establishment of donor stem cells in the recipient’s bone marrow. By growing and multiplying these cells, Zemcelpro increases the number of usable stem cells, thereby improving patient outcomes.

The EMA's recommendation follows an in-depth evaluation of data derived from two single-arm, open-label studies that included a total of 25 patients. According to Dr. Martin Keller, Chair of the Committee for Advanced Therapies (CAT) at the EMA, “The results from these studies indicate that 84% of patients achieved neutrophil engraftment within a median of 20 days, and 68% achieved platelet engraftment within a median of 40 days.” These outcomes are critical, as neutrophils are essential for fighting infections and platelets are necessary for blood clotting.

Despite its promising results, the therapy is not without risks. Common side effects reported include low blood cell counts, infections, high blood pressure, and engraftment syndrome. Moreover, acute graft-versus-host disease (GvHD) was observed in 60% of patients, while chronic GvHD appeared in 13% within the first year post-transplant. To address these potential complications, the EMA has outlined monitoring and mitigation strategies that must be adhered to as part of the therapy's risk management plan.

The recommendation for Zemcelpro’s conditional marketing authorization is a part of the EU’s regulatory framework that allows for faster patient access to treatments addressing unmet medical needs. This process permits drugs to be approved with less comprehensive data when the immediate benefits are deemed to outweigh the risks associated with incomplete information. Following this positive opinion from the EMA, the recommendation will be forwarded to the European Commission, which will make the final decision regarding EU-wide marketing authorization.

The development of Zemcelpro has been supported by the Priority Medicines (PRIME) scheme, which aims to enhance support for innovative therapies with significant potential to address critical health needs. Cordex Biologics International Limited, the company behind Zemcelpro, has been tasked with conducting long-term follow-up studies and randomized controlled trials to further validate the therapy's safety and efficacy.

Once marketing authorization is granted, individual member states will decide on pricing and reimbursement, taking into account the role of Zemcelpro within their respective healthcare systems. This potential approval marks a significant milestone in the ongoing fight against blood cancers, offering new hope to patients facing the daunting challenges of finding suitable donors for stem cell transplants.