Stem Cell Transplants Better Than New Therapies at Delaying Myeloma Progression, Analysis Finds

In an era of new therapies with unprecedented efficacy, high-dose therapy with melphalan followed by autologous stem cell transplant (HDT/ASCT) is still associated with better progression-free survival in newly-diagnosed multiple myeloma patients, researchers found. Autologous transplants use the patient’s own stem cells.

A meta-analysis of randomized Phase 3 trials, titled “Autologous Transplantation for Newly Diagnosed Multiple Myeloma in the Era of Novel Agent Induction: A Systematic Review and Meta-analysis,” was published in the journal JAMA Oncology.

HDT/ASCT has been the standard treatment for patients with multiple myeloma for two decades. But modern induction therapy with novel agents such as immunomodulatory drugs and proteasome inhibitors has shown significant effectiveness.

Researchers sought to re-think the role of HDT/ASCT. Interestingly, all studies conducted recently have shown a benefit in progression-free survival (PFS) in favor of HDT/ASCT, but the effect on response rate and overall survival compared with patients on standard-dose therapy (SDT) has been variable.

Therefore, researchers set out to perform a review of Phase 3 randomized controlled trials that compared HDT/ASCT with standard-dose therapy using new agents.

In their evaluation, the primary outcome was progression-free survival (PFS), while secondary outcomes included overall survival, complete response, and treatment-related mortality.

Results showed that patients who underwent HDT/ASCT had a 27% higher probability of having a complete response compared to patients receiving standard-dose therapy.

Among patients treated with stem cell transplants, the risk of disease progression or death was 45% lower than those receiving the novel agents. While a trend was observed for better overall survival among these patients, the findings were not statistically significant.

Patients who received tandem HDT/ASCT had the best results, with a reduction in the risk of progression or death by 51% compared to those receiving standard therapy with novel agents.

This was followed by treatment with single HDT/ASCT accompanied by consolidation with Velcade (bortezomib), Revlimid (lenalidomide), and dexamethasone, which reduced the risk of disease progression or death by 47%. Finally, a single transplant given alone was associated with a 32% lower risk.

When looking at overall survival, none of the transplant-based approaches had a significant effect. Treatment-related mortality for patients treated with HDT/ASCT was minimal.

“This modality (including tandem transplantation or single-transplant followed by consolidation with bortezomib, lenalidomide, and dexamethasone) when compared with standard-dose therapy was associated with superior progression-free survival,” the team concluded.

However, “none of the transplant-based approaches were associated with improved overall survival,” it added.

The researchers concluded that autologous stem cell transplant remains the preferred therapy in transplant-eligible patients with multiple myeloma.