Outcomes of VD-PACE With Immunomodulatory Agent as a Salvage Therapy for Relapsed/Refractory Multiple Myeloma

Real-world clinical outcomes in patients with relapsed and refractory multiple myeloma receiving VTD-PACE treatment in the era of monoclonal antibodies

Bortezomib (Velcade), thalidomide, dexamethasone, platinum (cisplatin), adriamycin (doxorubicin), cyclophosphamide, and etoposide (VTD-PACE) are commonly used as salvage treatment for patients with relapsed/refractory multiple myeloma (RRMM). However, its outcomes in the era of monoclonal antibodies remain unclear. Therefore, this retrospective cohort study assessed the clinical outcomes of 60 patients with RRMM (median four prior treatment lines) administered VTD-PACE. The median follow-up period was 11.1 months, during which they received a median of two cycles of VTD-PACE. The overall response rate (ORR) was 66.7%; ORRs of 53.1 and 82.1% were noted in patients with ≥ 4 and ≤ 3 prior lines (P = 0.027), respectively. The median overall survival (OS) was 17 months, with a median progression-free survival (PFS) of 9.8 months. Using the 3-month time point after VTD-PACE treatment as a landmark, 54 patients were still alive. Landmark analysis was conducted for PFS and OS of patients who received or did not receive HSCT or CART after VTD-PACE treatment. Patients who underwent subsequent hematopoietic stem cell transplantation (HSCT) or chimeric antigen receptor T-cell therapy (CART) following VTD-PACE showed a trend of longer PFS and OS than those who did not undergo subsequent HSCT or CART. The median OS in patients with and without renal dysfunction was 10.7 months and 21.5 months, respectively (P = 0.0091). Therefore, VTD-PACE is useful as a bridging therapy for HSCT or CART, as a response can be expected regardless of organ damage, disease risk, or history of anti-CD38 antibody use.

Bridging advanced myeloma patients to subsequent treatments and clinical trials with classical chemotherapy and stem cell support

Rapidly progressing relapsed/refractory multiple myeloma (RRMM) patients with compromised marrow have limited treatment options. Thus, non-myeloablative chemotherapy with a stem cell boost (SCB) may provide disease control and hematopoietic improvement as bridge to subsequent therapies. We identified 96 patients who received a SCB between January 2011 and December 2019 at the Mount Sinai Hospital. Patients had a median age of 64 years, received a median of 7 prior lines of therapy and 68 and 42% were triple-class and penta-drug refractory, respectively. Chemotherapy included melphalan (MEL) (n = 16), melphalan + carmustine (BCNU/MEL) (n = 52) or a variant of DCEP (dexamethasone, cyclophosphamide, etoposide, cisplatin) (n = 28). Median time to neutrophil recovery was 10 days and was significantly lower with DCEP (8 days) compared to MEL and BCNU/MEL (10-11 days) (p = 0.0047). Time to progression, progression-free survival and overall survival were 3.19, 2.7 and 8.38 months, respectively. The BCNU/MEL group had the highest response rate of 85% (p = 0.05), clinical benefit rate of 94% (p = 0.0014), progression-free survival of 3.3 months (p = 0.4) and overall survival of 8.7 months (p = 0.5). Sixty-six patients (69%) were bridged to new lines of therapy, including clinical trials. Non-myeloablative chemotherapy with SCB provides rapid disease control and marrow recovery with potential to receive further therapy.

VTd-PACE and VTd-PACE-like regimens are effective salvage therapies in difficult-to-treat relapsed/refractory multiple myeloma: a single-center experience

Although treatment options for multiple myeloma (MM) are rapidly evolving, there still remain difficult-to-treat situations, especially in relapsed and/or refractory (r/r) disease. When modern therapies are exhausted, or emergency treatment is needed for high tumor burden, classic chemotherapy combination regimens like the VTd-PACE regimen and its modifications (PACE-M) may also be beneficial as bridging to subsequent treatment options. This single-center retrospective analysis aimed to investigate the outcome of VTd-PACE and PACE-M salvage therapy in 31 heavily pretreated r/r MM patients. The primary objective was the overall response rate (ORR). Secondary objectives were median progression-free survival (mPFS), median overall survival (mOS), safety, and renal response. Median age was 59 years (range 39-75), and 71% of patients were male. R-ISS stratification showed high-risk MM in 48%. The median number of prior therapies was 3, with 23 patients being triple- and 12 penta-refractory (74% and 39%). ORR was 71%, including 23% of patients achieving a very good partial response. Median duration of follow-up was 15 months (range 0-29 months). mPFS and mOS were 3 months (95% CI 0.27-5.74) and 11 months (95% CI 3.66-18.35), respectively. In 26 patients (83.9%), at least one subsequent treatment (stem cell transplant or BCMA-directed) was administered. Renal function significantly improved after VTd-PACE or PACE-M treatment (p = 0.032). Non-hematological adverse events ≥ grade 3 were predominantly infections. VTd-PACE and PACE-M are effective salvage therapies in difficult-to-treat situations in heavily pre-treated r/r MM, including patients with impaired renal function. VTd-PACE and PACE-M can be successfully used as bridging therapy for subsequent treatment.

The first relapse in multiple myeloma: how to pick the next best thing

The choice of treatment for patients with multiple myeloma (MM) at first relapse/progression is based on many factors: (1) treatment-related factors, which include the regimen used during first induction, the quality and duration of first response achieved, toxicities from the first treatment, whether the patient underwent autologous stem cell transplant, and whether the patient was on maintenance at the time of relapse/progression; (2) disease-related factors, including disease presentation and pace of progression; and (3) patient-related factors, including functional age and performance status. The learning objectives are to present the treatment options for patients with MM upon their first relapse and to learn about various strategies for selecting an optimal treatment regimen.

Bortezomib-thalidomide-dexamethasone-cisplatin-doxorubicin-cyclophosphamide-etoposide as a Salvage and Bridging Regimen before Hematopoietic Stem Cell Transplantation for Relapsed or Refractory Multiple Myeloma

Objective Currently, treatment of relapsed or refractory multiple myeloma is challenging. Although bortezomib-thalidomide-dexamethasone-cisplatin-doxorubicin-cyclophosphamide-etoposide (VTD-PACE), a potent combination of a proteasome inhibitor, immunomodulatory drug, and conventional chemotherapeutics, is a widely used regimen, its efficacy and safety are unclear. Methods We retrospectively analyzed the clinical data of 35 patients treated with VTD-PACE. Results The overall response rate was 65.7% (complete response, 5.7%). The median progression-free survival (PFS) and overall survival (OS) were 8.0 [95% confidence interval (CI), 0.9-15.0] and 20.0 (95% CI, 17.5-22.5) months, respectively. Twenty-two (62.9%) patients developed grade 3-4 infections, and no therapy-related deaths occurred. Sixteen of 25 patients (64%) underwent stem cell harvest successfully with more than 2.0×10⁶/kg of CD34 cells after VTD-PACE. Twenty-two patients underwent autologous or allogeneic stem cell transplantation (SCT). The response and survival durations were short in patients without SCT after VTD-PACE [median PFS: 4.0 (95% CI, 2.7-5.3) months; OS: 14.0 (6.9-21.0) months]; however, these responses significantly improved with SCT following VTD-PACE. The PFS was 8.0 (NA) months (p=0.024), and the OS was 21.0 (19.1-22.8) months (p=0.019). Conclusion VTD-PACE is an effective and tolerable salvage regimen and feasible bridging therapy for SCT.

Outcomes of VDPACE with an immunomodulatory agent as a salvage therapy in relapsed/refractory multiple myeloma with extramedullary disease

Extramedullary disease (EMD) is an aggressive form of multiple myeloma (MM). Confirming the presence of plasma cells outside the bone marrow makes the diagnosis of EMD. There is no clear consensus on the management of EMD in MM, and this entity continues to remain an unmet need. Rapidly controlling EMD to prevent end-organ damage is a priority. Retrospectively, we reviewed our database for patients with EMD that received treatment with bortezomib, dexamethasone, cisplatin, doxorubicin, cyclophosphamide, etoposide (VDPACE) plus an immune modulator (IMiD) regimen. We identified 21 patients with a median age of 61 years. Ten patients received a VDPACE based regimen as a bridge to autologus stem cell transplant (ASCT). After a median follow-up of 51.4 months, the median overall survival (OS) and progression-free survival were 14.9 months (95% CI: 7.8-NA) and 5.5 months (95% CI: 3.9-NA), respectively. The overall response rate was 76%, with a manageable safety profile. Interestingly, these results were similar regardless of the presence of high-risk cytogenetics. The safety profile was acceptable. In conclusion, a salvage VDPACE-based regimen plus an IMiD remains an effective and safe bridging therapy to future ASCT and immunotherapy in relapsed/refractory multiple myeloma patients with EMD.

Outcomes after delayed and second autologous stem cell transplant in patients with relapsed multiple myeloma

We evaluated the outcomes of 168 patients undergoing delayed or second autologous stem cell transplant (ASCT) for relapsed multiple myeloma (MM) from 2010 to 2019. Overall, 21% (n = 35) patients had received a prior transplant and 69% (n = 116) underwent transplant at first relapse. Overall, 27% patients had high-risk cytogenetics and 15% had ISS stage III disease. Stem cell collection was performed after relapse in 72% and 35% of patients received maintenance therapy. Median PFS from salvage treatment and transplant were 28 and 19 months, respectively. Median OS from salvage treatment and transplant was 69 and 55 months. Multivariate analysis revealed that ASCT in first relapse was associated with superior PFS (HR 0.63, p = 0.03) and OS (HR 0.59, p = 0.04) compared to later lines of therapy. In addition, PFS of ≥36 months with prior therapy was associated with improved PFS (HR 0.62, p = 0.04) and OS (HR 0.41, p = 0.01). Ninety-five patients underwent delayed transplant at first relapse, median PFS and OS from start of therapy was 30 and 69 months, and median OS from diagnosis was 106 months. These data may serve as a guide when counseling patients undergoing ASCT for relapsed MM and provide a benchmark in designing clinical trials of transplantation/comparative treatments for relapsed MM.

Treatment Strategies Considering Micro-Environment and Clonal Evolution in Multiple Myeloma

Simple Summary

Multiple myeloma is an uncurable hematological malignancy, although the prognosis of myeloma patients is getting better using proteasome inhibitors (PIs), immune modulatory drugs (IMiDs), monoclonal antibodies (MoAbs), and cytotoxic agents. Drug resistance makes myeloma difficult to treat and it can be subdivided into two broad categories: de novo and acquired. De novo drug resistance is associated with the bone marrow microenvironment including bone marrow stromal cells, the vascular niche and endosteal niche. Acquired drug resistance is related to clonal evolution and non-genetic diversity. The initial treatment plays the most important role considering de novo and acquired drug resistance and should contain PIs, IMIDs, MoAbs, and autologous stem cell transplantation because these treatments improve the bone marrow microenvironment and might prevent clonal evolution via sustained deep response including minimal residual disease negativity.

Abstract

Multiple myeloma is an uncurable hematological malignancy because of obtained drug resistance. Microenvironment and clonal evolution induce myeloma cells to develop de novo and acquired drug resistance, respectively. Cell adhesion-mediated drug resistance, which is induced by the interaction between myeloma and bone marrow stromal cells, and soluble factor-mediated drug resistance, which is induced by cytokines and growth factors, are two types of de novo drug resistance. The microenvironment, including conditions such as hypoxia, vascular and endosteal niches, contributes toward de novo drug resistance. Clonal evolution was associated with acquired drug resistance and classified as branching, linear, and neutral evolutions. The branching evolution is dependent on the microenvironment and escape of immunological surveillance while the linear and neutral evolution is independent of the microenvironment and associated with aggressive recurrence and poor prognosis. Proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs), monoclonal antibody agents (MoAbs), and autologous stem cell transplantation (ASCT) have improved prognosis of myeloma via improvement of the microenvironment. The initial treatment plays the most important role considering de novo and acquired drug resistance and should contain PIs, IMIDs, MoAb and ASCT. This review summarizes the role of anti-myeloma agents for microenvironment and clonal evolution and treatment strategies to overcome drug resistance.