Comparing the outcomes of proteasome inhibitors versus immunomodulators as maintenance therapy for patients with newly diagnosed multiple myeloma.

This study compared the outcomes of proteasome inhibitors (PIs) versus immunomodulators (IMs) as maintenance therapy for patients with newly diagnosed MM. The data showed that PIs maintenance increased the survival outcomes compared to IMs in these patients.

Multiple myeloma (MM) is a type of cancer that comes from blood cells called plasma cells. A high number of patients with MM experience relapse (the tumor grows after treatment) or are refractory (not responsive to the treatment) to standard treatment. Maintenance therapy is usually recommended after first-line treatments to delay relapse in patients. Common treatments for MM include PIs such as bortezomib (Velcade) and IMs such as lenalidomide (Revlimid).

Proteasomes are large molecules present in all body cells. They break down and remove damaged proteins. MM cells rely on proteasomes to multiply and spread. PIs block the action of proteasomes, therefore preventing myeloma cells from growing and multiplying. IMs stimulate the immune system and can help to block cancer growth. There are few studies comparing the outcomes of PIs versus IMs as maintenance therapy for patients with newly diagnosed MM.

The study involved 226 patients with newly diagnosed MM. 181 patients received maintenance therapy and 45 patients did not receive maintenance therapy. The average follow-up time was 36.9 months.

The average survival without progression or cancer worsening was 41.1 months for patients in the maintenance group compared to 10.5 months in the no maintenance group. The average overall survival (OS) was not reached (exceeded the average follow-up period) for patients in the maintenance group compared to 38.6 months in the no maintenance group. 34.3% of the patients in the maintenance group responded to treatment compared to 13.3% for the no maintenance group.

In the maintenance group, 127 patients were treated with PIs and 54 with IMs. The average survival without progression or cancer worsening was 43.7 months for patients treated with PIs compared to 38.5 months for patients treated with IMs. The average OS was not reached for patients treated with PIs compared to 78.5 months for patients treated with IMs.

Patients achieving partial disappearance of the cancer after first-line and consolidation therapy had significantly longer survival rates after PIs maintenance compared to IMs. Patients younger than 65 years who received PIs had a significantly longer OS rate (81.5% vs 66.1%). High-risk patients who received PIs maintenance therapy had improved survival times than those who received IMs maintenance therapy.

The 5-year OS rate was significantly longer in patients who received more than 12 months of bortezomib-based maintenance therapy (91.9%) compared to those who were treated for less than 12 months (51.1%).

This study concluded that PIs maintenance therapy increased the survival outcomes compared to IMs in patients with newly diagnosed MM. PIs provided the most benefit in young and high-risk patients.

This study looked back in time at medical records. The sample size was small and the follow-up time was short.