Multiple myeloma: Maintenance therapy after autologous hematopoietic stem cell transplantation, depending on minimal residual disease

• Main Authors: M V Solovyev, L P Mendeleeva, O S Pokrovskaya, M V Nareyko, M V Firsova, I V Galtseva, Yu O Davydova, N M Kapranov, L A Kuzmina, E G Gemdzhian, V G Savchenko
• Format: Article
• Language: Russian
• Published: "Consilium Medicum" Publishing house 2017-07-01
• Series: Терапевтический архив
• Subjects: multiple myeloma; minimal residual disease; autologous hematopoietic stem cell transplantation; maintenance therapy
• Online Access: https://ter-arkhiv.ru/0040-3660/article/viewFile/32258/pdf

Aim. To determine the efficiency of maintenance therapy with bortezomib in patients with multiple myeloma (MM) who have achieved complete remission (CR) after autologous hematopoietic stem cell (auto-HSCT), depending on the presence of minimal residual disease (MRD). Subjects and methods. In January 2014 to February 2016, fifty-two MM patients (19 men and 33 women) aged 24 to 66 years (median 54 years), who had achieved CR after auto-HSCT, were randomized to perform maintenance therapy with bortezomib during a year. On day 100 after auto-HSCT, all the patients underwent immunophenotyping of bone marrow plasma cells by 6-color flow cytometry to detect MRD. Relapse-free survival (RFS) was chosen as a criterion for evaluating the efficiency of maintenance therapy. Results. After auto-HSCT, MRD-negative patients had a statistically significantly higher 2-year RFS rate than MRD-positive patients: 52.9% (95% confidence interval (CI), 35.5 to 70.5%) versus 37.2% (95% CI, 25.4 to 49.3%) (p=0.05). The presence of MRD statistically significantly increased the risk of relapse (odds ratio 1.7; 95% CI, 1.2 to 3.4; p=0.05). Two-year cumulative risk of relapse (using the Kaplan-Meier) after auto-HSCT did not statistically significantly differ in MRD-negative patients receiving (n=15) and not receiving (n=10) maintenance therapy with bortezomib (p=0.58). After completion of maintenance treatment, 42% of the MRD-positive patients achieved a negative status. In the MRD-positive patients who had received maintenance therapy, the average time to recurrence was 5 months longer than that in the naïve patients: 17.3 versus 12.3 months. Conclusion. The MRD status determined in MM patients who have achieved CR after auto-HSCT is an important factor for deciding on the use of maintenance therapy.