Single-point and kinetics of peripheral residual disease by mass spectrometry to predict outcome in patients with high risk smoldering multiple myeloma included in the GEM-CESAR trial.

The value of quantitative immunoprecipitation mass spectrometry (QIP-MS) to identify the M-protein is being investigated in patients with monoclonal gammopathies but no data are yet available in high-risk smoldering myeloma (HRsMM). We have therefore investigated QIP-MS to monitor peripheral residual disease (PRD) in 62 HRsMM patients enrolled in the GEM-CESAR trial. After 24 cycles of maintenance, detecting the M-protein by MS or clonal plasma cells by NGF identified cases with a significantly shorter median PFS (mPFS; MS: not reached vs 1,4 years, p=0.001; NGF: not reached vs 2 years, p=0.0002) but reaching CR+sCR did not discriminate patients with different outcome. With NGF as a reference, the combined results of NGF and MS showed a high negative predictive value (NPV) of MS: 81% overall and 73% at treatment completion. When sequential results were considered, sustained negativity by MS or NGF was associated with a very favorable outcome with a mPFS not yet reached vs 1.66 years and 2.18 years in cases never attaining PRD or minimal residual disease (MRD) negativity, respectively. We can thus conclude that 1) the standard response categories of the IMWG do not seem to be useful for treatment monitoring in HRsMM patients, 2) MS could be used as a non-invasive, clinical valuable tool with the capacity of guiding timely bone marrow evaluations (based on its high NPV with NGF as a reference) and 3) similarly to NGF, sequential results of MS are able identify a subgroup of HRsMM patients with long-term disease control. This study was registered at www.clinicaltrials.gov (ClinicalTrials.gov identifier: NCT02415413).

Patient-reported outcomes in relapsed/refractory multiple myeloma treated with melflufen plus dexamethasone: analyses from the Phase II HORIZON study.

Relapsed/refractory multiple myeloma (RRMM) is known to have a high burden of disease and complications associated with refractoriness to prior lines of therapy. Severe pain and fatigue symptoms and impairments in physical and emotional functioning have been strongly linked to reduced health-related quality of life (HRQoL) in patients with RRMM. Assessment of patient reported-outcome measures from the pivotal, Phase II HORIZON study (OP-106; NCT02963493) in patients with RRMM (n = 64) demonstrated that melphalan flufenamide (melflufen) plus dexamethasone treatment preserved HRQoL. Patients had clinically meaningful improvements, even after eight treatment cycles, in relevant scales such as global health status/QoL, physical functioning, emotional functioning, pain, and fatigue. Patients with triple-class-refractory disease (n = 50) displayed similar improvements. Patient-reported outcome deterioration was delayed for a substantial amount of time in patients who experienced a response to melflufen plus dexamethasone treatment relative to patients who did not experience a response. These findings support the notion that treatment with melflufen plus dexamethasone may sustain or improve HRQoL over time in patients with RRMM, including in patients with triple-class-refractory disease for whom outcomes are generally worse. The clinical benefits observed in patients from the HORIZON trial are encouraging and supportive of translation into real-world practice.

Subgroup analysis of ICARIA-MM study in relapsed/refractory multiple myeloma patients with high-risk cytogenetics.

Treatment benefit in multiple myeloma (MM) patients with high-risk cytogenetics remains suboptimal. The phase 3 ICARIA-MM trial (NCT02990338) showed that isatuximab plus pomalidomide-dexamethasone prolongs median progression-free survival (mPFS) in patients with relapsed/refractory MM (RRMM). This subgroup analysis of ICARIA-MM compared the benefit of isatuximab in high-risk [defined by the presence of del(17p), t(4;14) or t(14;16)] versus standard-risk patients. The efficacy of isatuximab in patients with gain(1q21) abnormality was also assessed in a retrospective subgroup analysis. In ICARIA-MM, 307 patients received isatuximab-pomalidomide-dexamethasone (n = 154) or pomalidomide-dexamethasone (n = 153). Isatuximab (10 mg/kg intravenously) was given weekly in the first 28-day cycle, and every other week thereafter. Standard pomalidomide-dexamethasone doses were given. Isatuximab-pomalidomide-dexamethasone improved mPFS (7·5 vs 3·7 months; HR, 0·66; 95% CI, 0·33-1·28) and overall response rate (ORR, 50·0% vs 16·7%) in high-risk patients. In patients with isolated gain(1q21), isatuximab addition improved mPFS (11·2 vs 4·6 months; HR, 0·50; 95% CI, 0·28-0·88) and ORR (53·6% vs 27·6%). More grade ≥3 adverse events occurred in high-risk patients receiving isatuximab (95·7%) versus the control group (67·6%); however, isatuximab did not increase events leading to discontinuation or treatment-related mortality. Isatuximab-pomalidomide-dexamethasone provides a consistent benefit over pomalidomide-dexamethasone treatment in RRMM patients regardless of cytogenetic risk.

Analysis of renal impairment in MM-003, a phase III study of pomalidomide + low - dose dexamethasone versus high - dose dexamethasone in refractory or relapsed and refractory multiple myeloma.

Pomalidomide + low-dose dexamethasone is effective and well tolerated for refractory or relapsed and refractory multiple myeloma after bortezomib and lenalidomide failure. The phase III trial MM-003 compared pomalidomide + low-dose dexamethasone with high-dose dexamethasone. This subanalysis grouped patients by baseline creatinine clearance ≥ 30 - < 60 mL/min (n=93, pomalidomide + low-dose dexamethasone; n=56, high-dose dexamethasone) or ≥ 60 mL/min (n=205, pomalidomide + low-dose dexamethasone; n=93, high-dose dexamethasone). Median progression-free survival was similar for both subgroups and favored pomalidomide + low-dose dexamethasone versus high-dose dexamethasone: 4.0 versus 1.9 months in the group with baseline creatinine clearance ≥ 30 - < 60 mL/min (P<0.001) and 4.0 versus 2.0 months in the group with baseline creatinine clearance ≥ 60 mL/min (P<0.001). Median overall survival for pomalidomide + low-dose dexamethasone versus high-dose dexamethasone was 10.4 versus 4.9 months (P=0.030) and 15.5 versus 9.2 months (P=0.133), respectively. Improved renal function, defined as an increase in creatinine clearance from < 60 to ≥ 60 mL/min, was similar in pomalidomide + low-dose dexamethasone and high-dose dexamethasone patients (42% and 47%, respectively). Improvement in progression-free and overall survival in these patients was comparable with that in patients without renal impairment. There was no increase in discontinuations of therapy, dose modifications, and adverse events in patients with moderate renal impairment. Pomalidomide at a starting dose of 4 mg + low-dose dexamethasone is well tolerated in patients with refractory or relapsed and refractory multiple myeloma, and of comparable efficacy if moderate renal impairment is present. This trial was registered with clinicaltrials.gov identifier 01311687 and EudraCT identifier 2010-019820-30.

Phase 1/1B trial of the heat shock protein 90 inhibitor NVP-AUY922 as monotherapy or in combination with bortezomib in patients with relapsed or refractory multiple myeloma.

BACKGROUND: NVP-AUY922 (AUY; Luminespib) with or without bortezomib showed preclinical activity against multiple myeloma (MM) cells. This phase 1/1B study assessed NVP-AUY922 alone and with bortezomib in patients with relapsed or refractory MM. METHODS: Dose escalation was guided by an adaptive Bayesian logistic regression model. In phase 1, patients who progressed after 2 to 4 prior therapies received NVP-AUY922 intravenously once weekly. In phase 1B, patients who progressed after 2 or fewer prior therapies received NVP-AUY922 plus bortezomib. The primary objective was to determine the maximum tolerated dose (MTD) of NVP-AUY922. RESULTS: Twenty-four patients received NVP-AUY922 monotherapy at doses of 8 to 70 mg/m(2) . One dose-limiting toxicity (DLT) was observed (grade 3 blurred vision at 70 mg/m(2) ); no MTD was reached. The recommended phase 2 dose was 70 mg/m(2) . The most frequent drug-related adverse events (AEs) were diarrhea, nausea, and ocular toxicities. Grade 3/4 AEs were uncommon (<10%). Eight patients discontinued treatment because of AEs; 5 had ocular toxicities (≥45 mg/m(2) ). The best response was stable disease in 66.7% of the patients. There were no partial or complete responses. Five patients received NVP-AUY922 (which was started at 50 mg/m(2) ) plus bortezomib (1.3 mg/m(2) ). Three of these patients experienced DLT. No further dose escalation was performed; the MTD for NVP-AUY922 plus bortezomib was not established. CONCLUSIONS: This study showed disease stabilization with NVP-AUY922 in patients with relapsed or refractory MM. The MTD for NVP-AUY922 was not reached, but reversible ocular toxicity has been reported at high dose levels. Bortezomib at the standard recommended dose plus NVP-AUY922 was not tolerated.

Bendamustine, bortezomib and prednisone for the treatment of patients with newly diagnosed multiple myeloma: results of a prospective phase 2 Spanish/PETHEMA trial.

Bendamustine is a bifunctional alkylating agent with proven activity in myeloma. In this study 60 newly diagnosed myeloma patients were given bendamustine plus bortezomib and prednisone in a regimen consisting of one cycle of bortezomib twice weekly for 6 weeks (1.3 mg/m(2) on days 1, 4, 8, 11, 22, 25, 29, and 32), plus bendamustine (90 mg/m(2) on days 1 and 4) and prednisone. The following cycles included bortezomib once weekly. Patients who were transplant candidates proceeded to stem cell collection after four cycles and the transplant was performed after six cycles. Patients who were not candidates for transplantation received up to nine cycles. Forty-two patients were transplant candidates and after six cycles, 50% achieved at least a very good partial response, with 24% having complete responses; 35 proceeded to a transplant, and the complete response rate was 54%. Seventeen patients continued up to nine cycles, and 57% achieved at least a very good partial response, including 26% with complete responses. The 2-year progression-free survival and overall survival rates were 62% and 86%, respectively. The safety profile was manageable, but stem cell mobilization was compromised in 35% of patients. In summary, this combination is effective in untreated patients, with an acceptable toxicity profile, but given the introduction of second-generation novel agents and monoclonal antibodies, the combination will probably be better reserved for relapsing patients, in whom stem cell collection is not needed, while cost-effective combinations with non-cross-resistant drugs continue to represent a medical need. This trial was registered with ClinicalTrials.gov, number NCT01376401.

Cytogenetics and long-term survival of patients with refractory or relapsed and refractory multiple myeloma treated with pomalidomide and low-dose dexamethasone.

Patients with refractory or relapsed and refractory multiple myeloma who no longer receive benefit from novel agents have limited treatment options and short expected survival. del(17p) and t(4;14) are correlated with shortened survival. The phase 3 MM-003 trial demonstrated significant progression-free and overall survival benefits from treatment with pomalidomide plus low-dose dexamethasone compared to high-dose dexamethasone among patients in whom bortezomib and lenalidomide treatment had failed. At an updated median follow-up of 15.4 months, the progression-free survival was 4.0 versus 1.9 months (HR, 0.50; P<0.001), and median overall survival was 13.1 versus 8.1 months (HR, 0.72; P=0.009). Pomalidomide plus low-dose dexamethasone, compared with high-dose dexamethasone, improved progression-free survival in patients with del(17p) (4.6 versus 1.1 months; HR, 0.34; P <0.001), t(4;14) (2.8 versus 1.9 months; HR, 0.49; P=0.028), and in standard-risk patients (4.2 versus 2.3 months; HR, 0.55; P<0.001). Although the majority of patients treated with high-dose dexamethasone took pomalidomide after discontinuation, the overall survival of patients treated with pomalidomide plus low-dose dexamethasone or high-dose dexamethasone was 12.6 versus 7.7 months (HR, 0.45; P=0.008) in patients with del(17p), 7.5 versus 4.9 months (HR, 1.12; P=0.761) in those with t(4;14), and 14.0 versus 9.0 months (HR, 0.85; P=0.380) in standard-risk subjects. The overall response rate was higher in patients treated with pomalidomide plus low-dose dexamethasone than in those treated with high-dose dexamethasone both among standard-risk patients (35.2% versus 9.7%) and those with del(17p) (31.8% versus 4.3%), whereas it was similar in patients with t(4;14) (15.9% versus 13.3%). The safety of pomalidomide plus low-dose dexamethasone was consistent with initial reports. In conclusion, pomalidomide plus low-dose dexamethasone is efficacious in patients with relapsed/refractory multiple myeloma and del(17p) and/or t(4;14). This study is registered at ClinicalTrials.gov as NCT01311687 and with EudraCT as 2010-019820-30.

Impact of prior treatment and depth of response on survival in MM-003, a randomized phase 3 study comparing pomalidomide plus low-dose dexamethasone versus high-dose dexamethasone in relapsed/refractory multiple myeloma.

Pomalidomide is a distinct oral IMiD(®) immunomodulatory agent with direct antimyeloma, stromal-support inhibitory, and immunomodulatory effects. The pivotal, multicenter, open-label, randomized phase 3 trial MM-003 compared pomalidomide + low-dose dexamethasone vs high-dose dexamethasone in 455 patients with refractory or relapsed and refractory multiple myeloma after failure of bortezomib and lenalidomide treatment. Initial results demonstrated significantly longer progression-free survival and overall survival with an acceptable tolerability profile for pomalidomide + low-dose dexamethasone vs high-dose dexamethasone. This secondary analysis describes patient outcomes by treatment history and depth of response. Pomalidomide + low-dose dexamethasone significantly prolonged progression-free survival and favored overall survival vs high-dose dexamethasone for all subgroups analyzed, regardless of prior treatments or refractory status. Both univariate and multivariate analyses showed that no variable relating to either the number (≤ or > 3) or type of prior treatment was a significant predictor of progression-free survival or overall survival. No cross-resistance with prior lenalidomide or thalidomide treatment was observed. Patients achieving a minimal response or better to pomalidomide + low-dose dexamethasone treatment experienced a survival benefit, which was even higher in those achieving at least a partial response (17.2 and 19.9 months, respectively, as compared with 7.5 months for patients with less than minimal response). These data suggest that pomalidomide + low-dose dexamethasone should be considered a standard of care in patients with refractory or relapsed and refractory multiple myeloma regardless of prior treatment. ClinicalTrials.gov: NCT01311687; EudraCT: 2010-019820-30.

High-risk cytogenetics and persistent minimal residual disease by multiparameter flow cytometry predict unsustained complete response after autologous stem cell transplantation in multiple myeloma.

The achievement of complete response (CR) after high-dose therapy/autologous stem cell transplantation (HDT/ASCT) is a surrogate for prolonged survival in multiple myeloma; however, patients who lose their CR status within 1 year of HDT/ASCT (unsustained CR) have poor prognosis. Thus, the identification of these patients is highly relevant. Here, we investigate which prognostic markers can predict unsustained CR in a series of 241 patients in CR at day +100 after HDT/ASCT who were enrolled in the Spanish GEM2000 (n = 140) and GEM2005 < 65y (n = 101) trials. Twenty-nine (12%) of the 241 patients showed unsustained CR and a dismal outcome (median overall survival 39 months). The presence of baseline high-risk cytogenetics by FISH (hazard ratio 17.3; P = .002) and persistent minimal residual disease by multiparameter flow cytometry at day +100 after HDT/ASCT (hazard ratio 8.0; P = .005) were the only independent factors that predicted unsustained CR. Thus, these 2 parameters may help to identify patients in CR at risk of early progression after HDT/ASCT in whom novel treatments should be investigated.

Superiority of bortezomib, thalidomide, and dexamethasone (VTD) as induction pretransplantation therapy in multiple myeloma: a randomized phase 3 PETHEMA/GEM study.

The Spanish Myeloma Group conducted a trial to compare bortezomib/thalidomide/dexamethasone (VTD) versus thalidomide/dexamethasone (TD) versus vincristine, BCNU, melphalan, cyclophosphamide, prednisone/vincristine, BCNU, doxorubicin, dexamethasone/bortezomib (VBMCP/VBAD/B) in patients aged 65 years or younger with multiple myeloma. The primary endpoint was complete response (CR) rate postinduction and post-autologous stem cell transplantation (ASCT). Three hundred eighty-six patients were allocated to VTD (130), TD (127), or VBMCP/VBAD/B (129). The CR rate was significantly higher with VTD than with TD (35% vs 14%, P = .001) or with VBMCP/VBAD/B (35% vs 21%, P = .01). The median progression-free survival (PFS) was significantly longer with VTD (56.2 vs 28.2 vs 35.5 months, P = .01). In an intention-to-treat analysis, the post-ASCT CR rate was higher with VTD than with TD (46% vs 24%, P = .004) or with VBMCP/VBAD/B (46% vs 38%, P = .1). Patients with high-risk cytogenetics had a shorter PFS and overall survival in the overall series and in all treatment groups. In conclusion, VTD resulted in a higher pre- and posttransplantation CR rate and in a significantly longer PFS although it was not able to overcome the poor prognosis of high-risk cytogenetics. Our results support the use of VTD as a highly effective induction regimen prior to ASCT. The study was registered with http://www.clinicaltrials.gov (NCT00461747) and Eudra CT (no. 2005-001110-41).

Zoledronic acid in the management of bone disease as a consequence of multiple myeloma: a review.

BACKGROUND: Multiple myeloma (MM) is a haematological cancer associated with organ damage, essentially bone damage. MM continues to be considered an incurable disease and requires significant therapeutic resources. AIM: This manuscript presents a literature review of the utility of zoledronic acid (zoledronate) in the management of bone disease in MM. DISCUSSION: The clinical benefit of bisphosphonates in the prevention and treatment of bone disease in MM has been demonstrated in the last 10 years. A recent network meta-analysis has evaluated 20 randomised clinical trials with nearly 7000 patients with myeloma enrolled and confirms the role of these agents in the prevention of pain, bone fractures and other skeletal-related events (SRE) in MM. However, their role on survival remains unclear. Zoledronate has shown significant reductions in SRE compared with placebo or other agents with acceptable tolerability, and recent studies have shown antitumoural effects for this agent, with a marginal survival benefit demonstrated in MM. CONCLUSIONS: Zoledronate prevents SRE in MM and presents a marginal survival benefit that deserves further investigation in controlled studies. Current clinical guidelines should be followed regarding the appropriate use of zoledronate in MM, to enhance its effects and to minimise its potential toxicity.

Pomalidomide plus low-dose dexamethasone versus high-dose dexamethasone alone for patients with relapsed and refractory multiple myeloma (MM-003): a randomised, open-label, phase 3 trial.

BACKGROUND: Few effective treatments exist for patients with refractory or relapsed and refractory multiple myeloma not responding to treatment with bortezomib and lenalidomide. Pomalidomide alone has shown limited efficacy in patients with relapsed multiple myeloma, but synergistic effects have been noted when combined with dexamethasone. We compared the efficacy and safety of pomalidomide plus low-dose dexamethasone with high-dose dexamethasone alone in these patients. METHODS: This multicentre, open-label, randomised phase 3 trial was undertaken in Australia, Canada, Europe, Russia, and the USA. Patients were eligible if they had been diagnosed with refractory or relapsed and refractory multiple myeloma, and had failed at least two previous treatments of bortezomib and lenalidomide. They were assigned in a 2:1 ratio with a validated interactive voice and internet response system to either 28 day cycles of pomalidomide (4 mg/day on days 1-21, orally) plus low-dose dexamethasone (40 mg/day on days 1, 8, 15, and 22, orally) or high-dose dexamethasone (40 mg/day on days 1-4, 9-12, and 17-20, orally) until disease progression or unacceptable toxicity. Stratification factors were age (≤75 years vs >75 years), disease population (refractory vs relapsed and refractory vs bortezomib intolerant), and number of previous treatments (two vs more than two). The primary endpoint was progression-free survival (PFS). Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01311687, and with EudraCT, number 2010-019820-30. FINDINGS: The accrual for the study has been completed and the analyses are presented. 302 patients were randomly assigned to receive pomalidomide plus low-dose dexamethasone and 153 high-dose dexamethasone. After a median follow-up of 10·0 months (IQR 7·2-13·2), median PFS with pomalidomide plus low-dose dexamethasone was 4·0 months (95% CI 3·6-4·7) versus 1·9 months (1·9-2·2) with high-dose dexamethasone (hazard ratio 0·48 [95% CI 0·39-0·60]; p<0·0001). The most common grade 3-4 haematological adverse events in the pomalidomide plus low-dose dexamethasone and high-dose dexamethasone groups were neutropenia (143 [48%] of 300 vs 24 [16%] of 150, respectively), anaemia (99 [33%] vs 55 [37%], respectively), and thrombocytopenia (67 [22%] vs 39 [26%], respectively). Grade 3-4 non-haematological adverse events in the pomalidomide plus low-dose dexamethasone and high-dose dexamethasone groups included pneumonia (38 [13%] vs 12 [8%], respectively), bone pain (21 [7%] vs seven [5%], respectively), and fatigue (16 [5%] vs nine [6%], respectively). There were 11 (4%) treatment-related adverse events leading to death in the pomalidomide plus low-dose dexamethasone group and seven (5%) in the high-dose dexamethasone group. INTERPRETATION: Pomalidomide plus low-dose dexamethasone, an oral regimen, could be considered a new treatment option in patients with refractory or relapsed and refractory multiple myeloma. FUNDING: Celgene Corporation.

Biological relapse in multiple myeloma: Outcome and treatment strategies in a Spanish real-world setting.

Recommendations regarding the best time to start treatment in patients with relapsed/refractory multiple myeloma (RRMM) after biological relapse/progression (BR) are unclear. This observational, prospective, multicenter registry aimed to evaluate the impact on time to progression (TTP) of treatment initiation at BR versus at symptomatic clinical relapse (ClinR) based on the Spanish routine practice in adult patients with RRMM. Patients had two or less previous treatment lines and at least one previous partial response. Baseline characteristics and treatment outcomes were recorded, and survival was analyzed. Of 225 patients, 110 were treated at BR (TxBR group) and 115 at ClinR (TxClinR group) according to the investigators' criteria. The proportion of patients with higher ECOG, previous noncomplete remission (CR), and second relapse were significantly higher in the TxBR group compared to the TxClinR group. TheTxClinR group showed improved outcomes, including TTP, compared to the TxBR group. Progression-free survival increased in the TxClinR group (56.2 months) compared to the TxBR group (32.5 months) (p = 0.0137), and median overall survival also increased (p = 0.0897). Median TTP was significantly longer in patients relapsing from a CR (50.4 months) and in their first relapse (38.7 months) compared to those relapsing from a non-CR response (32.9 months) and in their second relapse (25.2 months). Physicians seemed to start treatment earlier in RRMM patients with poor prognosis features. Previous responses to anti-MM treatment and the number of prior treatment lines were identified as prognosis factors, whereby relapse from CR and first relapse were associated with a longer time to progression.

COVID-19 Outcomes in Patients with Hematologic Malignancies in the Era of COVID-19 Vaccination and the Omicron Variant.

A greater understanding of clinical trends in COVID-19 outcomes among patients with hematologic malignancies (HM) over the course of the pandemic, particularly the Omicron era, is needed. This ongoing, observational, and registry-based study with prospective data collection evaluated COVID-19 clinical severity and mortality in 1818 adult HM patients diagnosed with COVID-19 between 27 February 2020 and 1 October 2022, at 31 centers in the Madrid region of Spain. Of these, 1281 (70.5%) and 537 (29.5%) were reported in the pre-Omicron and Omicron periods, respectively. Overall, patients aged ≥70 years (odds ratio 2.16, 95% CI 1.64-2.87), with >1 comorbidity (2.44, 1.85-3.21), or with an underlying HM of chronic lymphocytic leukemia (1.64, 1.19-2.27), had greater odds of severe/critical COVID-19; odds were lower during the Omicron BA.1/BA.2 (0.28, 0.2-0.37) or BA.4/BA.5 (0.13, 0.08-0.19) periods and among patients vaccinated with one or two (0.51, 0.34-0.75) or three or four (0.22, 0.16-0.29) doses. The hospitalization rate (75.3% [963/1279], 35.7% [191/535]), rate of intensive care admission (30.0% [289/963], 14.7% [28/191]), and mortality rate overall (31.9% [409/1281], 9.9% [53/536]) and in hospitalized patients (41.3% [398/963], 22.0% [42/191]) decreased from the pre-Omicron to Omicron period. Age ≥70 years was the only factor associated with higher mortality risk in both the pre-Omicron (hazard ratio 2.57, 95% CI 2.03-3.25) and Omicron (3.19, 95% CI 1.59-6.42) periods. Receipt of prior stem cell transplantation, COVID-19 vaccination(s), and treatment with nirmatrelvir/ritonavir or remdesivir were associated with greater survival rates. In conclusion, COVID-19 mortality in HM patients has decreased considerably in the Omicron period; however, mortality in hospitalized HM patients remains high. Specific studies should be undertaken to test new treatments and preventive interventions in HM patients.

Intravenous busulfan and melphalan as a conditioning regimen for autologous stem cell transplantation in patients with newly diagnosed multiple myeloma: a matched comparison to a melphalan-only approach.

Melphalan 200 mg/m(2) (MEL200) is the standard conditioning regimen administered to newly diagnosed patients with multiple myeloma (MM) undergoing autologous stem cell transplantation (ASCT). Few alternatives have been explored in order to improve the antimyeloma activity of this conditioning. We compare i.v. busulfan (BU) 9.6 mg/kg and MEL 140 mg/m(2) (MEL140) versus MEL200 mg/m(2) as a conditioning regimen before ASCT for newly diagnosed patients with MM. For this purpose, 51 patients receiving i.v. BU plus MEL were compared to 102 patients receiving MEL200 mg/m(2) in a 1:2 matched control analysis. Matching criteria included age, clinical stage at diagnosis, and response to induction therapy. No differences in the overall and complete response (CR) rates were observed after ASCT between both groups. After a median follow-up of 63 and 50 months in control and BU plus MEL groups, progression-free survival (PFS) was 24 and 33 months, respectively (P = .10). Most frequent toxicities included mucositis and febrile neutropenia in both groups. No case of sinusoidal obstruction syndrome was observed. Transplant-related mortality was 4% and 2% in BU plus MEL and control groups, respectively. ASCT conditioned with i.v. BU plus MEL may be considered an effective and well-tolerated alternative to a MEL-only approach as a conditioning regimen for patients with MM who are candidates for ASCT.

Clinical applicability and prognostic significance of molecular response assessed by fluorescent-PCR of immunoglobulin genes in multiple myeloma. Results from a GEM/PETHEMA study.

Minimal residual disease monitoring is becoming increasingly important in multiple myeloma (MM), but multiparameter flow cytometry (MFC) and allele-specific oligonucleotide polymerase chain reaction (ASO-PCR) techniques are not routinely available. This study investigated the prognostic influence of achieving molecular response assessed by fluorescent-PCR (F-PCR) in 130 newly diagnosed MM patients from Grupo Español Multidisciplinar de Melanoma (GEM)2000/GEM05 trials (NCT00560053, NCT00443235, NCT00464217) who achieved almost very good partial response after induction therapy. As a reference, we used the results observed with simultaneous MFC. F-PCR at diagnosis was performed on DNA using three different multiplex PCRs: IGH D-J, IGK V-J and KDE rearrangements. The applicability of F-PCR was 91·5%. After induction therapy, 64 patients achieved molecular response and 66 non-molecular response; median progression-free survival (PFS) was 61 versus 36 months, respectively (P = 0·001). Median overall survival (OS) was not reached (NR) in molecular response patients (5-year survival: 75%) versus 66 months in the non-molecular response group (P = 0·03). The corresponding PFS and OS values for patients with immunophenotypic versus non-immunophenotypic response were 67 versus 42 months (P = 0·005) and NR (5-year survival: 95%) versus 69 months (P = 0·004), respectively. F-PCR analysis is a rapid, affordable, and easily performable technique that, in some circumstances, may be a valid approach for minimal residual disease investigations in MM.

Multiparameter flow cytometry evaluation of plasma cell DNA content and proliferation in 595 transplant-eligible patients with myeloma included in the Spanish GEM2000 and GEM2005<65y trials.

The incorporation of high-dose therapy/autologous stem cell transplantation (HDT/ASCT) and novel agents has significantly improved survival in patients with multiple myeloma (MM), but whether this improvement also benefits patients harboring poor prognostic features, such as nonhyperdiploid MM (NH-MM) and a high proliferation index, remains largely unknown. We analyzed the DNA content and proliferation index of bone marrow plasma cells (PCs) by multiparameter flow cytometry in 595 newly diagnosed transplant-eligible patients with MM included in two consecutive PETHEMA/GEM trials: GEM2000 [VBMCP/VBAD (vincristine, carmustine, melphalan, cyclophosphamide, prednisone/vincristine, bischloroethylnitrosourea, adriamycin, and dexamethasone) followed by HDT/ASCT; n = 319] and GEM2005<65y (randomized induction with VBMCP/VBAD/bortezomib or thalidomide/dexamethasone or bortezomib/thalidomide/dexamethasone followed by HDT/ASCT; n = 276). Of the 595 patients, 295 were classified as NH-MM (49.6%) and 336 (56.5%) as high-proliferative MM (≥1% PCs in S-phase). Detection of NH-MM DNA content and ≥1% PCs in S-phase were of independent prognostic value for overall survival. Treatment with bortezomib-based regimens abrogated the inferior overall survival of patients with ≥1% PCs in S-phase but not of patients with NH-MM. Finally, a comparative analysis of PC proliferation index at diagnosis versus disease progression showed a twofold increase at relapse in 44 of 52 patients (85%) analyzed at both time points. NH-MM and a high proliferation index assessed by multiparameter flow cytometry remain as independent prognostic factors in MM, but the latter may be overcome by incorporating novel agents in the HDT/ASCT setting.

Long-term prognostic significance of response in multiple myeloma after stem cell transplantation.

For establishing the true effect of different response categories in patients with multiple myeloma (MM) treated with autologous stem cell transplantation, we evaluated, after a median follow-up of 153 months, 344 patients with MM who received a transplant between 1989 and 1998. Overall survival (OS) at 12 years was 35% in complete response (CR) patients, 22% in near complete response (nCR), 16% in very good partial response (VGPR), and 16% in partial response (PR) groups. Significant differences in OS and progression-free survival were found between CR and nCR groups (P = .01 and P = .002, respectively), between CR and VGPR groups (P = .0001 and P = .003), or between CR and PR groups (P = .003 and P = < 10(-5)); no differences were observed between the nCR and VGPR groups (P = .2 and P = .9) or between these groups and the PR group (P = .1 and P = .8). A landmark study found a plateau phase in OS after 11 years; 35% patients in the CR group and 11% in the nCR+VGPR+PR group are alive at 17 years; 2 cases had relapsed in the nCR+VGPR+PR group. In conclusion, MM achieving CR after autologous stem cell transplantation is a central prognostic factor. The relapse rate is low in patients with > 11 years of follow-up, possibly signifying a cure for patients in CR.