Evaluating the effectiveness and safety of adding ixazomib to lenalidomide maintenance therapy in patients with newly diagnosed multiple myeloma after ASCT.

This study evaluated the effectiveness and safety of adding ixazomib (Ninlaro) to lenalidomide (Revlimid) maintenance therapy after autologous stem cell transplant (ASCT) in patients with newly diagnosed multiple myeloma (MM). The data showed that the addition of ixazomib to lenalidomide maintenance improved survival without cancer worsening with manageable side effects in these patients.

MM is a type of cancer that comes from blood cells called plasma cells. The current recommended treatment for newly diagnosed MM involves first-line treatment with lenalidomide in combination with dexamethasone (Decadron) and bortezomib (Velcade), followed by ASCT and maintenance therapy. ASCT involves transplanting healthy stem cells from the same patient. Lenalidomide is an immunotherapy drug which boosts the body’s immune system to help it attack cancer cells. While this approach improved survival without cancer worsening and quality of life, it was non-curative for most patients.

Maintenance therapy is usually recommended after first-line treatments to delay relapse or slow down cancer progression in patients. Common maintenance therapy includes treatment with proteasome inhibitors (PIs) such as ixazomib. 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. Ixazomib blocks the action of proteasomes, therefore preventing myeloma cells from growing and multiplying.

Currently, maintenance therapy with lenalidomide after ASCT is recommended, as this has been observed to improve outcomes after ASCT. However, it is not known if adding ixazomib to lenalidomide maintenance after ASCT would improve the effectiveness and safety in patients with newly diagnosed MM.

This study involved 64 patients with newly diagnosed MM. All patients previously underwent ASCT and then started on maintenance therapy with lenalidomide and ixazomib within 60-180 days of stem cell infusion. The average follow-up time was 62 months.

The complete response (complete disappearance of the cancer) rate was 42.2%. Overall, 89.1% of patients had a very good response (cancer shrinkage).

The average overall survival was not reached (exceeded the average follow-up time). After 5 years, 88.4% of the patients were alive. The overall average survival without cancer worsening was 73.3 months. After 5 years, 69% of the patients were alive without cancer worsening. 

The most common side effects were low white blood cell counts, low platelet counts, lung infections, diarrhea, and skin rash.

This study concluded that the addition of ixazomib to lenalidomide maintenance after ASCT improved survival without cancer worsening with manageable side effects in patients with newly diagnosed MM.

The sample size was very small. There was no control arm. Larger studies with longer follow-ups are necessary to validate the conclusions. This study was funded by Takeda, the manufacturer of ixazomib.