Multiple Myeloma: New Treatments Aid Patient Subgroups

Is the risk for relapse high?

It is very high, in the sense that almost all patients with multiple myeloma eventually relapse. However, we hope that there soon will be some patients who do not relapse.

What are the typical pathologic manifestations of this cancer? Does it affect everyone equally, or in specific ways in each person?

In multiple myeloma, we often say there are multiple myelomas. Clinically, the disease presents in most patients, around 80%, with two clinical manifestations: anemia and bone lesions. Less frequently, patients may also have kidney failure, hypercalcemia, and a higher tendency toward infection. Behind this rather common symptomatology, from a molecular and genetic perspective, each myeloma is practically unique, adding complexity to its treatment. Therefore, ultimately, myelomas end up being refractory.

Elranatamab is a new therapeutic tool. For which patients is it recommended?

It is a bispecific monoclonal antibody that corresponds to the new monotherapy strategies we have for treating patients with multiple myeloma. On the one hand, it targets damaged plasma cells, which are the patient’s tumor cells, and on the other, it binds the patient’s T cells and redirects them to the tumor niche. When this happens, the T cell activates and destroys the tumor cell.

This medication has been approved for patients with relapsed myeloma who have received traditional drugs for their treatment. We know well that patients who have already received proteasome inhibitors, immunomodulators, and anti-CD38 antibodies typically need something new after treatment. Before, there were no other options, and we would reuse what had been previously used. Now we have elranatamab, a bispecific monoclonal antibody targeting a new receptor that has shown significant responses as monotherapy.

More than 60% of patients respond, and more than 30% achieve complete remission. The key is the response duration and progression-free survival of almost a year and a half. This is the longest progression-free survival we have seen to date in previous lines. Therefore, it fills the needs we had for these relapsed or refractory myeloma patients.
 

What advantages does this new treatment offer?

It represents a therapeutic innovation because, as mentioned, it achieves a response in more than 60% of patients, and around 35% achieve complete remission. The median response duration has not been reached yet. Progression-free survival is 17.2 months, almost a year and a half, and overall survival is almost two years. 

Furthermore, it is administered as subcutaneous monotherapy weekly for the first six cycles and then every 15 days. It has a good safety profile, although some adverse events are known, so we have strategies to combat or mitigate them, making the treatment generally well tolerated.
 

What side effects are being observed?

They are manageable. When the drug is first administered, patients may experience what we call a cytokine release syndrome, which is a result of the treatment’s mechanism. However, we can predict very well when it occurs, usually 2 days after the first doses, and we have strategies to mitigate it.

The second most common adverse event we need to be cautious about is infection. Nowadays, before starting treatment, patients update their vaccination schedule, receive antiviral prophylaxis, and receive prophylaxis against certain germs, resulting in reduced infections. However, infections are probably the adverse events we need to be most careful about when treating the patient.

We must ensure that prophylaxis is performed, and if fever occurs and an infection is suspected, cultures and all kinds of studies must be done to identify and treat it properly.