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ToTem: a phase 1 trial of donor ‘effector memory’ T cells to improve immune system recovery after donor (allogeneic) stem cell transplants

This is a phase 1 (early phase) trial of an experimental treatment. Little is known about the safety and effectiveness of this treatment. You might not benefit from the treatment, but the trial will give important information about this new treatment, which could help other people in the future.

Purpose of trial

People who have a stem cell transplant using donor stem cells (an allogeneic stem cell transplant) are at risk of developing graft-versus-host disease. This is when donor cells attack your own tissues. Current treatments for graft-versus-host disease lower your immune function. However, this increases your risk of developing a serious infection.

The aim of this trial is to find out whether it is safe to give a particular type of donor T cell to people who have had an allogeneic stem cell transplant in order to boost immune system recovery without causing graft-versus-host disease.


Everyone in this trial is given donor ‘effector memory’ T cells through a drip into a vein (an intravenous infusion). You have the cells between 24 and 32 days after your stem cell transplant.

Effector memory T cells are a type of T cell that are involved in ‘remembering’ infections you have had before so your immune system can respond quickly if you come across the same infection again. Lab studies have shown that effector memory T cells might help your immune system recover after an allogeneic stem cell transplant without causing graft-versus-host disease.

In this trial, T cells are collected from your stem cell donor. The process of collecting the T cells is very similar to stem cell collection. The cells are collected between 14 days before and 24 days after your stem cell transplant. The T cells are then sent to a central lab where effector memory T cells are separated from other types of T cell.

Who can enter

Your consultant can give you advice on whether you might be suitable for this trial.

Around 18 people are needed for this trial.

You may be able to enter if:

  • You have non-Hodgkin lymphoma, Hodgkin lymphoma or chronic lymphocytic leukaemia (CLL). The study is also recruiting people with some other types of blood cancer, primary immune deficiency or aplastic anaemia.
  • You need a donor (allogeneic) stem cell transplant.
  • Your medical team plans to use medicines called alemtuzumab or calcineurin inhibitors (for example, ciclosporin) to prevent graft-versus-host disease.
  • You have a brother or sister who is a suitable stem cell donor.
  • Your lymphoma has completely or partially responded to your salvage therapy.
  • You are well enough to take part in the trial.
  • Your blood and other health test results are satisfactory.
  • You and your partner are willing to use reliable contraception if there is any chance of you or your partner becoming pregnant.
  • You are aged between 16 and 69.

You won’t be able to enter if:

  • You have any health problems that your doctor thinks might make it unsafe for you to have the trial treatment.
  • Your heart, kidney or liver function is not good enough.
  • You have ever had graft-versus-host disease before.
  • You have had treatment with cellular therapies before (for example, T cells or a previous allogeneic stem cell transplant).
  • Your lymphoma comes back or gets worse during the trial.
  • The donor stem cells fail to settle in your bone marrow and make new blood cells (graft failure).
  • Your medical team plans to use medicines other than alemtuzumab or calcineurin inhibitors (for example, ciclosporin) to prevent graft-versus-host disease.
  • You are pregnant or breastfeeding.
  • You are taking part in another clinical trial that involves active treatment.

Further information

More information about this trial is available at