Since 2021, the FDA has approved two CAR-T therapies for multiple myeloma. These new treatments offer potential options for patients with relapsed/refractory multiple myeloma. Ongoing clinical trials continue to explore promising new applications of CAR-T therapies.
Read on to learn more about the effect of CAR-T cell therapy on multiple myeloma.
What is CAR-T Therapy?
Chimeric antigen receptor, or CAR, T-cell therapy is an immunotherapy that’s personalized for every patient. Infection-fighting cells, known as T-cells, are removed from the patient’s body. The cells are then sent to a lab, where they’re genetically altered to have CAR cells on their surface.
CAR cells help T-cells seek out and attach to proteins found in cancer cells. The altered T-cells are replicated in the lab, then reintroduced to the patient’s body. Here, they seek out and bind to proteins on cancer cells, and may persist in the body for months.
The process was first approved by the FDA in 2017. Since then, it’s primarily been used to treat certain types of blood cancer, such as leukemia, lymphoma and myeloma.
In March 2021, the FDA approved the first CAR T-cell therapy for use with multiple myeloma patients. In February of 2022, a second treatment was approved. These therapies are authorized for patients who’ve gone through four lines of prior treatment, including proteasome inhibitors, immunomodulatory drugs and CD38 antibodies, and have relapsed or not responded well to (are refractory) previous treatments.
How CAR T-cell Therapies Treat Multiple Myeloma
Multiple myeloma often responds well to immuno-based treatments, such as CAR-T therapy. The two approved CAR-T therapies — Idecabtagene vicleucel (also known as ide-cel or Abecma) and ciltacabtagene autoleucel (also known as cilta-cel or Carvykti) — target a specific protein found on myeloma cells.
The therapies both work by binding to BCMA proteins on myeloma cells. The latest approved treatment, cilta-cel, actually targets two different regions of the BCMA protein. This differentiates cita-cel from other treatments that only target a single region. It’s also prescribed on a weight-based basis, resulting in a lower dosage, and is considered a one-time treatment.
Clinical trials have shown promising results thus far. In one early study, most patients had already undergone six (non-CAR-T) treatments. In this trial, 98 percent of patients showed a response, with 83 percent showing a deep response. Two years after the study, the PFS (progression free survival) rate is at 60 percent, results described as “impressive.”
Results from the CARTITUDE-1 clinical trial showed that 78 percent of patients had no sign of cancer in their bone marrow or blood, known as a stringent complete response. The response rate had a median length of 22 months.
In contrast, other treatments for multiple myeloma show only about a 30 percent response rate. Most clita-cel patients were able to forgo other cancer treatments during remission, which improved their quality of life. In most cases, side effects were similar to those from other CAR T-cell therapies, such as infections, nerve issues and cytokine release syndrome.
CAR-T therapies show promise for patients with multiple myeloma. Clinical trials continue, offering hope for patients and their families.