EU/3/20/2265: Orphan designation for the treatment of acute myeloid leukaemia

Acute myeloid leukaemia (AML) is a cancer of the white blood cells (cells that fight infection). In patients with AML, the bone marrow (the spongy tissue inside the large bones where blood cells are produced) produces white blood cells that are not fully developed and do not work properly. These abnormal cells quickly build up in large numbers in the bone marrow and are then found in the blood.

AML is a life-threatening disease because these abnormal white blood cells replace the normal blood cells in the bone marrow and the blood, causing bleeding episodes, blood clots and reduced ability to fight infections.

At the time of designation, AML affected approximately 1.6 in 10,000 people in the European Union (EU). This was equivalent to a total of around 83,000 people*, and is below the ceiling for orphan designation, which is 5 people in 10,000. This is based on the information provided by the sponsor and the knowledge of the Committee for Orphan Medicinal Products (COMP).

* For the purpose of the designation, the number of patients affected by the condition is estimated and assessed on the basis of data from the European Union, Iceland, Liechtenstein, Norway and the United Kingdom. This represents a population of 519,200,000 (Eurostat 2020).

Treatment for AML depends on a number of factors, including the extent of the disease, whether it has been treated before, symptoms and general state of health. At the time of designation, several medicines were authorised for treating AML. Patients might also receive stem cell transplantation, a procedure where the patient's bone marrow is cleared of cells and replaced by stem cells to form new bone marrow that produces healthy blood cells.

The sponsor has provided sufficient information to show that the medicine might be of significant benefit for patients with AML because early results from studies show that when given in combination with azacitidine (another cancer medicine), cusatuzumab could improve the response to treatment in patients who were not well enough to receive intensive chemotherapy (high doses of medicines that kill cancer cells or stop them growing). This assumption will need to be confirmed at the time of marketing authorisation, in order to maintain the orphan status.

Cusatuzumab is a monoclonal antibody (a type of protein) designed to attach to a protein called CD70. This protein is found on cancer cells, including AML cells, and is involved in the growth of the cancer. By binding to CD70, cusatuzumab is expected to block the growth of the cancer, thus slowing down the progression of the disease.

The effects of cusatuzumab have been evaluated in experimental models.

At the time of submission of the application for orphan designation, clinical trials with cusatuzumab in patients with AML were ongoing.

At the time of submission, cusatuzumab was not authorised anywhere in the EU for the treatment of AML. Orphan designation of cusatuzumab had been granted in the USA for this condition.

In accordance with Regulation (EC) No 141/2000, the COMP adopted a positive opinion on 19 March 2020, recommending the granting of this designation.

• the seriousness of the condition;
• the existence of alternative methods of diagnosis, prevention or treatment;
• either the rarity of the condition (affecting not more than 5 in 10,000 people in the EU) or insufficient returns on investment.

Designated orphan medicinal products are products that are still under investigation and are considered for orphan designation on the basis of potential activity. An orphan designation is not a marketing authorisation. As a consequence, demonstration of quality, safety and efficacy is necessary before a product can be granted a marketing authorisation.