What is stem cell therapy?
Haematopoietic “stem” cells are a special type of cells present in the bone marrow, the soft tissue inside bones. These cells have the potential to develop into any kind of cells based on physiological triggers for differentiation. They may be used in the treatment of many difficult-to-treat diseases including cancers, and disorders of the blood and the immune system. Skin stem cells have for long been used to grow skin grafts where large parts of the body have been burnt. However, it remains a very specialised form of treatment.
What is “matching” in the context of stem cell transplant?
In planning stem cell therapy, proteins present on white blood cells, called human leukocyte antigens (HLA), are matched. If HLA is not matched, healthy cells from the transplant could attack the host cells — a condition known as “graft versus host disease”, or GVHD. The closest HLA matches are usually between siblings, as humans get one half of their HLA from the mother and other half from the father. This means that a parent is half a match — and every sibling has a 25% chance of being a match. There may be unrelated matches too, which is where a stem cell donor registry comes in. In case no donor is available, there is the option of cord blood transplant, where stem cells from the umbilical cord may be used. In case of a relative, a haplotype mismatched transplant is also an option. In some conditions, autologous stem cells, that is, stem cells from the recipient, may be used.
What went wrong in the case of Harleen Kaur, the child who died in Ludhiana in November 2014?
Harleen was to have undergone a stem cell transplant for thalassaemia. Prior to such a transplant actually taking place, her own diseased cells had to be killed by chemotherapy. By the time the donor — who was contacted through a Chennai-based stem cell registry, and has remained anonymous — decided to back out at the last minute, Harleen had already undergone the sessions of chemotherapy, and was in a precarious stage. Doctors at Christian Medical College and Hospital (CMCH), Ludhiana, tried to procure stem cells through an international registry, but Harleen lost the battle before they could arrive. Her family now says that had her own cells been preserved instead of killing them, she might have made it.
What is the position of the Department of Health Research on stem cell therapy?
In 2013, the Department of Health Research and Department of Biotechnology jointly came up with National Guidelines for Stem Cell Research, a revision of the earlier 2007 guidelines. In the foreword, Dr V M Katoch, then Secretary, Health Research, and Dr K Vijayaraghavan, then Secretary, DBT, wrote: “Several clinical trials have been carried out using autologous or allogenic CD34+ve haematopoietic stem cells or mesenchymal stem cells (MSCs) in a variety of clinical indications but most of these have been Phase I or early Phase II trials. There is no conclusive proof of safety or therapeutic efficacy of stem cells in any condition yet. Unfortunately, some clinicians have started exploiting hapless patients by offering unproven stem cell treatments prematurely. Such fraudulent practices need to be stopped urgently, while ensuring that scientifically designed and responsible research on stem cells is not hindered.”
So, is stem cell therapy allowed in thalassaemia treatment?
Stem cell therapy is allowed for haematological conditions like thalassaemia and sickle cell anaemia, and some forms of blood-related cancers. However, all other applications are as per the government’s position; trials need all the necessary clearances for a clinical trial and, in case it is being marketed, also a nod from the Drug Controller General of India. It has to be registered in the clinical trial registry, requires informed consent for subjects as per clinical trial guidelines, and needs to compensate them if something goes wrong. Which is also why there are no government registries either. There are only a handful of functional donor registries in India, all of them managed by the non-government sector. There are many international donor registries, but Indians have a slimmer chance of encountering a match there because of the different ethnicity and profiles of potential donors in those registries.
What then, are the laws that govern stem cell therapy?
There are none. It is an unregulated sector in India. In fact, the omission of the word ‘therapy’ from the ICMR Guidelines — the only authentic rule document in the field — in 2013, was deliberate. “One major recommendation of the (drafting) Committee has been to omit the word Therapy from the title of the Guidelines. This has been done to emphasise the fact that stem cells are still not a part of standard of care; hence there can be no guidelines for therapy until efficacy is proven. These guidelines are intended to cover only stem cell research, both basic and translational, and not therapy.”
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