ctDNA improves prognostic prediction for patients with relapsed/refractory MM receiving ixazomib, lenalidomide, and dexamethasone.

ABSTRACT: It remains elusive how driver mutations, including those detected in circulating tumor DNA (ctDNA), affect prognosis in relapsed/refractory multiple myeloma (RRMM). Here, we performed targeted-capture sequencing using bone marrow plasma cells (BMPCs) and ctDNA of 261 RRMM cases uniformly treated with ixazomib, lenalidomide, and dexamethasone in a multicenter, prospective, observational study. We detected 24 and 47 recurrently mutated genes in BMPC and ctDNA, respectively. In addition to clonal hematopoiesis-associated mutations, varying proportion of driver mutations, particularly TP53 mutations (59.2% of mutated cases), were present in only ctDNA, suggesting their subclonal origin. In univariable analyses, ctDNA mutations of KRAS, TP53, DIS3, BRAF, NRAS, and ATM were associated with worse progression-free survival (PFS). BMPC mutations of TP53 and KRAS were associated with inferior PFS, whereas KRAS mutations were prognostically relevant only when detected in both BMPC and ctDNA. A total number of ctDNA mutations in the 6 relevant genes was a strong prognostic predictor (2-year PFS rates: 57.3%, 22.7%, and 0% for 0, 1, and ≥2 mutations, respectively) and independent of clinical factors and plasma DNA concentration. Using the number of ctDNA mutations, plasma DNA concentration, and clinical factors, we developed a prognostic index, classifying patients into 3 categories with 2-year PFS rates of 57.9%, 28.6%, and 0%. Serial analysis of ctDNA mutations in 94 cases revealed that TP53 and KRAS mutations frequently emerge after therapy. Thus, we clarify the genetic characteristics and clonal architecture of ctDNA mutations and demonstrate their superiority over BMPC mutations for prognostic prediction in RRMM. This study is a part of the C16042 study, which is registered at www.clinicaltrials.gov as #NCT03433001.

Autologous HSCT with novel agent-based induction and consolidation followed by lenalidomide maintenance for untreated multiple myeloma.

Triplet regimen comprising proteasome inhibitors, immunomodulatory drugs, and dexamethasone (DEX) is a recommended induction/consolidation therapy for multiple myeloma (MM) patients eligible for transplant. In this Japanese phase II study conducted from 2017 to 2019, newly diagnosed MM patients aged 20-65 received four induction cycles with bortezomib (Bor), lenalidomide (Len), and DEX (VRD), followed by Bor and high-dose melphalan with autologous stem cell rescue. Subsequently, they underwent four consolidation cycles with carfilzomib, Len, and DEX (KRD), followed by Len maintenance until disease progression. A total of 141 patients were analyzed. In an intent-to-treat population, the complete or better response post induction was 19.9%, rising to 39.7%, 58.9%, and 62.4% after transplant, consolidation, and 1-year maintenance, respectively. With a median follow-up of 38 months, the 3-year progression-free survival (PFS) rate was 83.5% and the 3-year overall survival rate was 92.5%. Severe adverse events (≥grade 3) occurred in ~30% of patients; however, there was no treatment-related mortality. These findings clearly showed the tolerability and effectiveness of this protocol. Nevertheless, patients with high-risk cytogenetics showed a trend toward lower 3-year PFS than those without (77.8% vs. 89.4%, p = 0.051), and ultra-high-risk cytogenetics (≥2 high-risk cytogenetics) had an even worse prognosis, with 61.2% 3-year PFS. To overcome this situation, a more potent treatment strategy incorporating novel agents such as the CD38-antibody should be assessed in future studies.

A multi-center, phase Ib study of subcutaneous administration of isatuximab in combination with pomalidomide and dexamethasone in patients with relapsed/refractory multiple myeloma.

Not available.

An observational study of once-weekly carfilzomib in patients with multiple myeloma in Japan (Weekly-CAR study).

Background: The ARROW study demonstrated that once-weekly carfilzomib and dexamethasone (wKd) therapy significantly prolonged progression-free survival compared with twice-weekly carfilzomib and dexamethasone therapy in relapsed or refractory multiple myeloma patients. Aim: To describe the treatment patterns, effectiveness and safety of wKd therapy in real-world settings in Japan. Methods: We investigated data from the medical records of 126 Japanese patients with relapsed or refractory multiple myeloma. Results: The overall response rate was 66.3%. The median progression-free survival was 9.5 months. The incidence of treatment-emergent adverse events of any grade and grade ≥3 were 45.8 and 20.8%, respectively. Conclusion: There were no new or unexpected safety signals in this study. This study demonstrated the effectiveness and safety profiles of wKd therapy in Japan.

Carfilzomib became available for daily clinical practice as a drug for cancer of bone marrow (multiple myeloma) that comes back or does not respond to previous drug (relapsed or refractory). This drug was approved in the USA in 2012, and in Japan in 2016. In this study, we looked at how once-weekly carfilzomib works and how safe it is in real-life situations in Japan. We screened 126 patients with relapsed or refractory multiple myeloma in Japan. The median age of the patients was 70 years, with 25% being over 75 years. This study also included some patients who were not in the best overall health, had a history of many treatments or had heart complications. In 66.3% of patients, the cancer had disappeared or the extent of the cancer had reduced after treatment. Side effects and serious side effects occurred in 45.8 and 14.2% of patients, respectively. The most common side effects were low levels of blood platelets (9.2%), high blood pressure (5.8%), loose or watery stools (5.0%), fever (5.0%), and low levels of red blood cells (4.2%). Heart disorders occurred in five patients. But all patients recovered or improved with treatment such as blood pressure lowering drugs and diuretics. These results showed that once-weekly carfilzomib works well and is safe in real-world settings in Japan. This information can help us think about how to pick the right patients and handle heart disease risks when using carfilzomib treatment.

Primary analysis of a prospective cohort study of Japanese patients with plasma cell neoplasms in the novel drug era (2016-2021).

The emergence of novel drugs has significantly improved outcomes of patients with plasma cell neoplasms (PCN). The Japanese Society of Hematology conducted a prospective observational study in newly diagnosed PCN patients between 2016 and 2021. The analysis focused on 1385 patients diagnosed with symptomatic PCN between 2016 and 2018. The primary endpoint was the 3-year overall survival (OS) rate among patients requiring treatment (n = 1284), which was 70.0% (95%CI 67.4-72.6%). Approximately 94% of these patients received novel drugs as frontline therapy. The 3-year OS rate was 90.3% (95%CI 86.6-93.1%) in the 25% of patients who received upfront autologous stem cell transplantation (ASCT), versus just 61.4% (95%CI 58.0-64.6%) in those who did not receive upfront ASCT. The only unfavorable prognostic factor that affected OS in ASCT recipients was an age of 65 or higher. For patients who did not receive ASCT, independent unfavorable prognostic factors included frontline treatment with conventional chemotherapies, international staging system score of 2/3, extramedullary tumors, and Freiberg comorbidity index of 2/3. This study unequivocally demonstrates that use of novel drugs improved OS in Japanese myeloma patients, and underscores the continued importance of upfront ASCT as the standard of care in the era of novel drugs.