Consultant Haematologist, Beaumont RCSI Cancer Centre
Multiple myeloma (MM) is a blood cancer that affects the immune system, blood counts and bones and can lead to significant disability and distress for patients. Nearly all patients experience relapse, but there are treatment options that can help.
Enormous advances have been made in the treatment of multiple myeloma, particularly in the past decade. However, it remains incurable in the long term. This means that patients require close monitoring after the initial disease has been successfully treated (remission) and will require further treatment once the disease comes back (relapse).
Finding treatment for relapsed myeloma
A number of factors will influence which treatment is suitable for a patient when the disease relapses. In most cases, treatment will be somewhat personalised to that patient, ensuring that they get the most suitable drug(s) for them at the right time.
Patient factors that influence treatment choice include age, general health, other diseases (eg. cardiac disease, diabetes) and side effects from previous treatment (eg. neuropathy). Disease factors include how long it has been since the last treatment (remission duration) and how aggressively the disease is behaving. For example, at relapse, some patients may require dialysis for kidney failure or radiation to treat bone or spinal fractures.
A number of factors will influence which treatment is suitable for a patient when the disease relapses.
Drugs and clinical trials offering treatment
The drugs chosen to treat MM at relapse will also depend on side effects, previous drugs the patient may have received and which therapies have shown to be most effective in clinical trials. Indeed, clinical trials form an important part of treatment for relapsed MM patients as they offer the patient the best available treatment for the disease; and often, these treatments are not available outside of clinical trials.
The categories of drugs available in Ireland to MM patients include a combination of immunomodulatory drugs (pomalidomide, lenalidomide), proteasome inhibitors (bortezomib, carfilzomib, ixazomib), monoclonal antibodies (daratumumab, isatuximab) and traditional chemotherapy agents like cyclophosphamide.
Newer categories of drugs include bispecific antibodies (teclistamab, elranatamab) and antibody-drug conjugates (belantamab mafodotin) are currently only available in Ireland in clinical trials. These therapies offer patients a chance to receive a completely new class of drug for their disease and have resulted in excellent remission rates in clinical trials.
Trialling cellular therapies for multiple myeloma
The development of cellular therapies such as CAR-T cells for MM has also produced unprecedented results for patients in terms of reducing — or completely removing — all traces of MM. These are also currently still undergoing clinical trials.