CAR-T cell treatments
Chimeric antigen receptor T (CAR-T) cell treatment is one of the most novel treatments for myeloma. It represents a type of personalised medicine and works by genetically modifying a patient’s own T cells to enable them to find and kill myeloma cells in a more directed manner, rather than relying on drugs to initiate and maintain this response. CAR-T clinical trials are currently available for both newly diagnosed and relapsed/refractory myeloma patients, for up-to-date information please see the Myeloma Trial Finder.
As with other immunotherapies, most of these drugs work by enhancing the ability of T cells to recognise the protein BCMA that is expressed at high levels on the surface of myeloma cells. Clinical research shows they can deliver longer remission times even in heavily pre-treated patients.
The following animation describes what CAR-T cell treatment is, and the different stages involved in the treatment process. The IMWG consensus guidelines offer recommendations for the management and response assessment of CAR-T cell treatment in myeloma.
CAR-T cell treatment takes several weeks. The process is outlined below.
- Leukapheresis is the first step in the process. A patient’s blood is drawn from a vein and T cells are extracted through an apheresis machine, which then returns the blood back into the body. This can take a few hours.
- The T cells are transferred to the laboratory where they are genetically modified into CAR-T cells that are now able to recognise myeloma cells. They must be multiplied to create the correct dose, a process that takes around 2–3 weeks. During this time the patient receives bridging treatment to keep their myeloma under control.
- A few days prior to receiving CAR-T cells back into the body, the patient undergoes lymphodepletion through treatment with chemotherapy. This prepares the body for the new cells.
- Through a drip over a few hours CAR-T cells are returned to the patient’s body through a process called adoptive T cell transfer. The patient is closely monitored during this time and for a few weeks after.
Side effects
CAR-T cell treatment carries the risk of both mild and serious side effects which can occur very quickly or a few weeks after T cell transfer. Milder effects include anaemia, increased risk of infections (due to cytopenia), and bleeding/bruising. Two particularly serious side effects are cytokine release syndrome (CRS) and neurotoxicity which can necessitate more urgent and supportive care, though for some patients they can be easily managed with timely intervention.
Cytokine release syndrome (infusion reaction) occurs most often in the first few days after treatment, when the newly introduced CAR-T cells cause a rapid and over-release of cytokines. The resulting symptoms include fever, rapid heart rate, nausea and body aches. Neurotoxic side effects (including immune effector cell-associated neurotoxicity syndrome (ICANs)) include confusion, reduced alertness, and difficulty speaking and most frequently occur within the first week. Nurses and other medical staff should be closely observing, treating and reporting these symptoms. CRS and ICANS assessment via the ASTCT consensus grading system should be carried out at least twice per day for all patients receiving CAR-T cell treatment, and managed accordingly. Many hospitals have their own specific protocols to follow which nurses should be familiar with.
As CAR-T cell treatment is a relatively new treatment, the medical team involved in supporting patients through this process should look out for any additional side effects and report them promptly. CAR-T therapy has gained a lot of attention in the news and therefore patients are likely to ask questions about this treatment to their team. It is important that nurses are able to understand their queries and support those going through CAR-T cell treatment, both emotionally and physically.