8. Somatic-cell therapy medicines
These medicines contain cells or tissues that have been biologically changed. Note that the cells are non-sex (non-germline) cells. The cells or tissues can be autologous (taken from the individual patient) or allogeneic (taken from another person, who might be related to the patient).
An example of somatic cell therapy is the use of a patient’s own immune cells. The cells are changed so that they can recognise and attack tumour cells when they are put back into the patient.
‘Stem cell’ therapy is one type of somatic cell therapy that has received widespread media attention. The goal of stem cell therapy is to replace tissues that are damaged due to illness or injury. This is done by ‘growing’ new tissue from stem cells (‘regeneration’). For example, the dead heart muscle found in heart failure, or the dopamine-producing cells damaged in Parkinson’s disease.
Another important use of stem cell therapy is haematopoietic stem cell transplantation (HSCT). The stem cells transplanted in this procedure are not changed, therefore HSCT is not referred to as somatic cell therapy.
- Haematopoietic stem cells in the bone marrow are essential for the production of blood cells.
- Chemotherapy and/or radiotherapy will partly or totally destroy the bone marrow of patients who are treated for blood or bone marrow cancers.
- HSCT is used to remove and then re-introduce haematopoietic stem cells into patients after such treatment, and allow them to start producing blood cells again.
There has been a dramatic increase in our knowledge about stem cells in the past few years. Also an increase in research and investment into their use as medicines. No medicines based on stem cells have yet received a marketing authorisation in the European Union (EU), but the EMA has offered advice to companies that develop these medicines for a number of years. Read more here.
Despite their promise, however, there is doubt about the possible drawbacks of using stem cells in medicines. Risks could be serious and unpreditable such as the development of tumours and rejection by the body.
The EMA has expressed concerns about patients who are seriously ill and who travel to clinics around the world for stem-cell-based treatments that are not authorised. Some clinics offer therapies at a high cost, without ethical approval, and there are serious concerns about their safety and efficacy. Read more here.