Thrombosis in multiple myeloma: Risk estimation by induction regimen and association with overall survival.

Lenalidomide-containing (R) triplet and quadruplet regimens are the standard of care for multiple myeloma (MM) and have been shown to increase the risk of thrombosis. The association between thromboembolism (TE) and survival in the novel multidrug era is not yet delineated. In this study, we evaluated the incidence of TE during the first year of MM diagnosis, its association with the type of induction regimen, and its impact on overall survival. We studied 672 newly diagnosed MM (NDMM) patients who received a triplet or quadruplet lenalidomide-based induction at the Mayo Clinic, Rochester. TE was diagnosed in 83 patients (12.4%). Of these, 56 (8.3%) had a deep venous thrombosis (DVT), 23 (3.4%) had a pulmonary embolism (PE) with or without the DVT, and 4 (0.6%) patients had a stroke. Carfilzomib-Rd (KRd) had the highest risk of TE (21.1%, 18/85), followed by quadruplets (11.1%, 5/45), bortezomib-Rd (9.6%, 51/531), and 0/11 (0%), treated with other lenalidomide-containing regimens. The difference in TE risk between KRd and the other regimens was statistically significant (OR = 2.6, p < .01). Nine patients developed a TE before being exposed to any treatment. Survival was significantly lower among patients that developed a TE (66 vs. 133 months, p < .01). The association of TE with reduced survival demonstrated in univariate analysis (HR = 2.2, 95% CI = 1.6-3.3) was maintained in the multivariable analysis adjusted for high-risk interphase fluorescence in situ hybridization (FISH), sex, age, receipt of an upfront transplant, the response at induction, and the International Staging System (ISS) (HR = 2.61, CI = 1.74-3.9). We conclude that TE is an important aspect of MM management, and effective management is especially relevant in the novel treatment era.

Risk factors for severe infection and mortality In patients with COVID-19 in patients with multiple myeloma and AL amyloidosis.

Patients with multiple myeloma (MM) have a lower efficacy from COVID-19 vaccination and a high rate of mortality from COVID-19 in hospitalized patients. However, the overall rate and severity of COVID-19 infection in all settings (including non-hospitalized patients) and the independent impact of plasma cell-directed therapies on outcomes needs further study. We reviewed the medical records of 9225 patients with MM or AL amyloidosis (AL) seen at Mayo Clinic Rochester, Arizona, and Florida between 12/01/2019 and 8/31/2021 and identified 187 patients with a COVID-19 infection (n = 174 MM, n = 13 AL). The infection rate in our cohort was relatively low at 2% but one-fourth of the COVID-19 infections were severe. Nineteen (10%) patients required intensive care unit (ICU) admission and 5 (3%) patients required mechanical ventilation. The mortality rate among hospitalized patients with COVID-19 was 22% (16/72 patients). Among patients that were fully vaccinated at the time of infection (n = 12), two (17%) developed severe COVID-19 infection, without any COVID-related death. On multivariable analysis, treatment with CD38 antibody within 6 months of COVID-19 infection [Risk ratio (RR) 3.6 (95% CI: 1.2, 10.5), p = .02], cardiac [RR 4.1 (95% CI: 1.3, 12.4), p = .014] or pulmonary comorbidities [RR 3.6 (95% CI 1.1, 11.6); p = .029] were independent predictors for ICU admission. Cardiac comorbidity [RR 2.6 (95% CI: 1.1, 6.5), p = .038] was an independent predictor of mortality whereas MM/AL in remission was associated with lower mortality [RR 0.4 (95% CI: 0.2-0.8); p = .008].

Multicentric Castleman disease: A single center experience of treatment with a focus on autologous stem cell transplantation.

Castleman disease (CD) is a rare lymphoproliferative disease characterized by diverse clinical and pathologic features. Due to its rarity, there are limited studies comparing currently available therapies. The role of autologous stem cell transplantation (ASCT) in CD has not yet been established. In this paper, we describe the clinical characteristics, treatment choices, and outcomes in 34 Mayo Clinic patients diagnosed with multicentric CD from July 1, 2003 to April 30, 2018. Eighteen patients (53%) also met the criteria for POEMS, including 14 with the osteosclerotic variant. The first-line treatments included: steroid monotherapy (4), cytotoxic chemotherapy (6), rituximab alone (8) or with chemotherapy (2), anti-IL6 treatment (3), and ASCT (10). The median follow-up was 4.8 (range: 0.1-15.2) years. The 5- and 10-year overall survival rates were 84% and 71%, respectively. Sixteen patients received high-dose chemotherapy followed by ASCT during their disease course. Among those, 14 had multicentric CD associated with POEMS. There were no transplant-related deaths. All patients had at least a partial response to ASCT, most of whom achieved a complete response. The favorable outcomes seen with ASCT in this cohort suggest that transplantation may have a role in multicentric CD, particularly for patients with multicentric CD associated with POEMS.

Comparison of the current renal staging, progression and response criteria to predict renal survival in AL amyloidosis using a Mayo cohort.

Three sets of criteria (International Society of Amyloidosis [ISA], Palladini and Kastritis) were independently developed for staging, progression and response criteria to predict renal survival in patients with AL amyloidosis. We evaluated these criteria using a cohort of 495 newly diagnosed AL amyloidosis patients with renal involvement using time to event competing risk analysis at baseline, 3, 6 and 12 months after treatment. Only Palladini and Kastritis had a staging system and both predicted a higher risk of end stage renal disease (ESRD) in the stage III vs stage I patients but only the Palladini model was predictive for stage II patients. At 3 months, risk of ESRD was significantly higher for Palladini and ISA renal progression (hazard ratio [HR] 2.8 [95% CI: 1.5-5.3, p = .001] and 2.5 [CI: 1.4-4.6, p = .004, respectively]), but renal response was not significantly protective; conversely, the risk of ESRD was not significantly higher for the Kastritis renal progression, but was significantly protective for the Kastritis renal responders (HR 0.38 [95% CI: 0.17-0.84], p = .017). Both progression and response with ISA, Palladini and Kastritis criteria were predictive of ESRD at 6 months and 12 months. While the Palladini staging criteria at baseline, and the ISA and Palladini criteria for progression at 3 months performed better than the Kastritis criteria at baseline and 3 months post-treatment, the Kastritis criteria performed better for response 3 months after treatment. All three sets of criteria performed well at and after 6 months post-treatment. These differences are important when choosing endpoints for clinical trials.

Substratification of patients with newly diagnosed standard-risk multiple myeloma.

Despite the absence of high-risk cytogenetics and lower International Staging System (ISS) stages, a subset of patients with multiple myeloma (MM) experience poor overall survival (OS). We studied 1461 patients with newly diagnosed MM to identify patient and disease characteristics that predict a high-risk phenotype among standard-risk patients. Fifty-six percent of all patients presented with standard-risk disease. Among them, advanced age, extremes of body mass index, non-hyperdiploid karyotype and abnormal lymphocyte counts were associated with worse OS. Standard-risk patients with 0-1 of these adverse factors (hazard ratio [HR] 0·32, 95% confidence interval [CI] 0·24-0·43, P < 0·001) and 2 adverse factors (HR 0·54, 95% CI 0·41-0·72, P < 0·001) experienced better OS than high-risk patients. Two or more adverse factors were present in 17% of standard-risk patients and were associated with OS comparable to high-risk patients (HR 0·91, 95% CI 0·67-1·24, P = 0·548). Predictive power among standard-risk patients was improved using score groups compared to ISS stages. Patients with standard-risk MM are a heterogeneous group with one in six patients experiencing OS comparable to high-risk disease. Patients at risk can be identified using readily available patient and disease characteristics. These findings emphasize the importance of accurate risk stratification and help explain part of the heterogeneity observed in clinical practice.

Delineation of the timing of second-line therapy post-autologous stem cell transplant in patients with AL amyloidosis.

Among patients with immunoglobulin light chain (AL) amyloidosis, there is little consensus on when reinstitution of chemotherapy should occur. We conducted a retrospective study to evaluate the patterns of relapse or progression (R/P) and the timing of reinitiating therapy among 235 patients initially treated with autologous stem cell transplant (ASCT) at Mayo Clinic. The median time from ASCT to second-line therapy was 24.3 months. At the time of restarting therapy, median difference of free light chain (dFLC) was 9.9 mg/dL (42% of diagnosis value), 32% had a dFLC <5 mg/dL, and 63% met criteria for organ R/P. The indications for retreatment were (1) clinical suspicion of R/P, 10%; 92) hematologic R/P only, 23%; (3) organ R/P only, 32%; (4) both hematologic and organ R/P, 31%; and (5) suboptimal response to ASCT and second-line therapy as consolidation, 4%. Patients with organ progression at the time of second-line therapy had inferior survival. Although a dFLC of >5 mg/dL at the time of reinstituting therapy was associated with risk, patients relapsing from very good partial response (VGPR) or better had a longer time to develop organ progression after hematologic R/P (24.2 vs 3.2 months, P = .007). These data suggest that the best candidates for clinical trials testing novel plasma cell-directed chemotherapy beyond first line may be those patients who are either relapsing from VGPR or better (dFLC at diagnosis was >5 mg/dL) or having inadequate response to prior therapy. This strategy should allow for hematologic response assessment while avoiding the risk of deleterious organ progression. Implementation of more stringent progression criteria may also be warranted.

Peripheral blood biomarkers of early immune reconstitution in newly diagnosed multiple myeloma.

Peripheral blood biomarkers of tumor microenvironment and immune surveillance are independent prognostic factors in multiple myeloma. The timing and prognostic impact of immune reconstitution has been studied after autologous hematopoietic stem cell transplantation, less is known about its significance in newly diagnosed multiple myeloma. We studied absolute lymphocyte (ALC) and absolute monocyte (AMC) counts at the time of treatment initiation and 1 month thereafter in 771 newly diagnosed patients. Two hundred and thirty-four patients (31%) had evidence of immune dysregulation at baseline (abnormal biomarkers). Eighty-seven of these patients (37%) recovered normal biomarkers at 1 month (early immune reconstitution). The absence of immune dysregulation at baseline (compared to the presence thereof) was associated with better overall survival (HR 0.77, 95% CI 0.61-0.97, P = 0.025, n = 771). The absence of immune dysregulation at 1 month (compared to the persistence or development thereof) was associated with better overall survival (HR 0.63, 95% CI 0.50-0.80, P < 0.001, n = 771). Early immune reconstitution (compared to the persistence or development of immune dysregulation) was associated with better overall survival (HR 0.62, 95% CI 0.43-0.92, P = 0.016, n = 771). Cytogenetic high-risk disease was negatively, and treatment with immunomodulators positively, associated with early immune reconstitution. The presence or development of immune dysregulation in newly diagnosed multiple myeloma is an independent risk factor. The favorable impact of early immune reconstitution suggests immune dysregulation to be a potentially modifiable risk factor that may be exploited for therapeutic benefit.

Prognostic value of minimal residual disease and polyclonal plasma cells in myeloma patients achieving a complete response to therapy.

Achievement of a complete response has been associated with improved outcomes in patients with multiple myeloma. Recently, increasing application of minimal residual disease (MRD) assessment has shown that MRD negativity is a powerful prognostic factor for survival outcomes. We wanted to examine the impact of the polyclonal plasma cell (pPC) compartment among patients in complete response (CR) but are MRD positive. This is a retrospective cohort study where 460 myeloma patients were identified who met criteria for CR and had multicolor flow cytometry performed on the bone marrow (BM). Monoclonal and pPCs were estimated during MRD testing. Final outcomes including overall survival (OS) and time to next treatment (TTNT) were compared among the groups. The median OS for the entire cohort was not reached (95% CI; 63 mos, NR) and the median TTNT was 31 months (95% CI; 27,36). Among the MRDneg group, median TTNT was 37.6 months vs 23 months for MRDpos patients (P < .001); the median OS was not reached for either group, but there was a trend toward better survival for MRDneg patients. Among the MRDpos group, median percentage of pPCs was 65% (2.5-98.5), and those with >95% pPCs had a significantly better TTNT (NR vs 23 months; P = .02) and a trend toward better OS. We conclude that achievement of MRD negativity predicts for better response durability and trend toward improved OS and an increased proportion of pPC predicts for better outcomes within those who have residual tumor cells highlighting the importance of marrow normalization.

Randomized phase 2 trial of ixazomib and dexamethasone in relapsed multiple myeloma not refractory to bortezomib.

Proteasome inhibitors have become an integral part of myeloma therapy. Considerable efforts have gone into optimizing this therapeutic approach to obtain maximal proteasome inhibition with least toxicity. Ixazomib is the first oral proteasome inhibitor to enter the clinic and has been studied as a single agent as well as in various combinations. The current trial was designed to examine the efficacy and toxicity of combining 2 different doses of ixazomib (4 mg and 5.5 mg given weekly for 3 of 4 weeks) with 40 mg weekly of dexamethasone, in relapsed myeloma. Seventy patients were enrolled, 35 patients randomly assigned to each ixazomib dose. Overall, 30 (43%; 95% confidence interval, 31-55) of the patients achieved a confirmed partial response or better, with 31% achieving a response with 4 mg and 54% with 5.5 mg of ixazomib. The median event-free survival (EFS) for the entire study population was 8.4 months; 1-year overall survival was 96%. The EFS was 5.7 months for patients with prior bortezomib exposure and 11.0 months for bortezomib-naïve patients. A grade 3 or 4 adverse event considered at least possibly related to treatment was seen in 11 (32%) patients at 4 mg and in 21 (60%) at 5.5 mg. Dose reductions were more frequent with 5.5 mg dose. Overall, the ixazomib with dexamethasone has good efficacy in relapsed myeloma, is well-tolerated and with higher response rate at 5.5 mg, albeit with more toxicity. This study was registered at www.clinicaltrials.gov as #NCT01415882.

Time to plateau as a predictor of survival in newly diagnosed multiple myeloma.

Response rates in newly diagnosed multiple myeloma have improved dramatically with the introduction of highly effective novel therapies. However, survival in patients achieving optimal responses to initial treatment can vary significantly, and new prognostic indicators are required to improve risk stratification. We investigated the relationship between time to plateau (TPlat ) and survival in 1099 newly diagnosed patients treated with novel agents at our institution from 2005 to 2015. TPlat was defined as time from initiation of first-line therapy to best response to first-line therapy. The median TPlat was 4.9 months (0.7-58.6) and plateau duration was 1.8 years (0.2-11.0). Patients who required > 120 days to achieve a plateau had longer modified overall survival (mOS) and progression free survival (mPFS) calculated from a landmark of best response (P < .001 for both comparisons). Statistically significant improvement in mOS was retained in subgroup analysis based on age and whether patients received upfront autologous hematopoietic stem cell transplantation (ASCT) (P < .001 for all comparisons). Our results suggest that patients who respond more gradually to initial therapy (TPlat > 120 days) experience longer survival compared to more rapid responders. Patients with a prolonged TPlat could represent an "ongoing responder" phenotype that portends a survival advantage independent of treatment with upfront ASCT, depth of response, and biologic markers such as ISS stage and cytogenetic risk.

Beta-blockers improve survival outcomes in patients with multiple myeloma: a retrospective evaluation.

A preclinical study demonstrated anti-proliferative and apoptotic effect of propranolol on multiple myeloma (MM) cell. Clinical studies suggested that beta-blocker (BB) might impact the prognosis of breast, prostate, colorectal, ovarian, lung, and skin cancer. This retrospective study evaluated the effect of BB in MM disease-specific survival (DSS) and overall survival (OS). Among 1,971 newly diagnosed MM patients seen at Mayo Clinic between 1995 and 2010, usage of BB and other cardiac (or antihypertensive) medications were abstracted. Cumulative incidence function and Kaplan-Meier method were used to estimate 5-year cumulative incidence rate (CIR) of MM death and OS rate, respectively. Nine hundred and thirty (47.2%) patients had no intake of cardiac medications; 260 (13.2%) used BB alone; 343 (17.4%) used both BB/non-BB cardiac medications; and 438 (22.2%) had non-BB cardiac drugs. Superior MM DSS was observed in BB only users, compared to patients without any cardiac drugs ( HRadj.CS, 0.53, 95% confidence interval [CI], 0.42-0.67, Padj. <0.0001) and non-BB cardiac drugs users ( HRadj.CS, 0.49, 95% CI, 0.38-0.63, Padj. <0.0001). Patients on both BB and other cardiac drugs showed superior DSS than non-cardiac drugs users ( HRadj.CS, 0.54, 95% CI, 0.44-0.67, Padj. <0.0001) and non-BB cardiac drug users. ( HRadj.CS, 0.50, 95% CI, 0.40-0.62, Padj. <0.0001). MM DSS did not differ between BB users with and without other cardiac drugs (Padj. =0.90). Multivariable analysis showed the same pattern for OS. In patients with MM, BB intake is associated with a reduced risk of disease-specific death and overall mortality in comparison to non-BB or no use of cardiac drugs. Am. J. Hematol. 92:50-55, 2017. © 2016 Wiley Periodicals, Inc.

The prognostic significance of polyclonal bone marrow plasma cells in patients with relapsing multiple myeloma.

Prior studies have revealed that the presence of increasing number of polyclonal plasma cells (pPCs) in the bone marrow (BM) are associated with better outcomes in newly diagnosed multiple myeloma (MM) patients. This effect has not been studied in patients with MM at the time of disease relapse. We determined the prognostic value of depletion of pPCs in the BM by 7-color multiparameter flow cytometry in a series of 174 relapsing MM patients. The time to next therapy (TTNT) in those with <5% pPCs was 9.4 months versus 13.9 months in those with ≥5% pPCs (P = .0091). The median overall survival (OS) in those with <5% pPCs was 21.4 months, while the median OS was not reached in those patients with ≥5% pPCs (P = .019). Of the 109 patients with standard risk cytogenetics, the median OS of those with <5% pPCs was 28.4 months, while the median OS was not reached in those with ≥5% pPCs (P = .033). As such, <5% pPCs in the BM appears to have prognostic utility in identifying a subset of relapsing MM patients, even with standard-risk cytogenetics, who have a particularly adverse outcome.

Efficacy of daratumumab-based therapies in patients with relapsed, refractory multiple myeloma treated outside of clinical trials.

Outside of clinical trials, experience with daratumumab-based combination therapies (DCTs) using bortezomib (V)/lenalidomide (R)/pomalidomide (P), and dexamethasone (d) in relapsed/refractory multiple myeloma (RRMM) is limited. We reviewed the outcomes of 126 patients who received ≥ 1 cycle of any DCT. Median age at DCT initiation was 67 (range, 43-93) years. High-risk cytogenetics was present in 33% patients. Median number of prior therapies was 4 (range, 1-14) and time to first DCT from diagnosis was 4.3 years (range, 0.4-13.0). Seventeen (13%) patients were refractory to single agent daratumumab. Fifty-two (41%), 34 (27%), 23 (18%), and 17 (14%) received DPd, DRd, DVd and "other" DCTs, respectively. Overall response rate was 47%. Median follow-up was 5.5 months (95% CI, 4.2-6.1). Median progression-free survival (PFS) was 5.5 months (95% CI, 4.2-7.8). Median overall survival was not reached (NR) with any regimen. Median PFS (months) was worst for penta-refractory MM (n = 8) vs quadruple refractory MM (n = 18) and others (n = 100) (2.2 [95% CI, 1-2.4] vs 3.1 [95% CI, 2.1-NR] vs 5.9 [95% CI, 5.0-NR]; P < .001); those who were refractory to ≥1 agents used in the DCT vs others (4.9 [95% CI, 3.1-6.0] vs 8.2 [95% CI, 4.6-NR]; P = .02); and those who received >2 prior therapies vs others (5.0 months [95% CI, 3.7-5.9] vs NR [95% CI, NR-NR]; P = .002). Non-hematologic toxicities included infections (38%), fatigue (32%), and infusion reactions (18%). Grade 3 or higher hematological toxicities were seen in 41% of patients. DCTs are effective in RRMM. ORR and PFS in heavily pretreated patients are lower than those reported in clinical trials.

N-terminal fragment of the type-B natriuretic peptide (NT-proBNP) contributes to a simple new frailty score in patients with newly diagnosed multiple myeloma.

Multiple myeloma (MM) patient frailty has been delineated primarily by age and ECOG performance score (PS) and recently by the IMWG frailty score based on functional status [Activity of Daily Living (ADL) and Instrumental-ADL scores], comorbidities [Charlson-comorbidity-index (CCI)] and age. It was hypothesized that N-terminal natriuretic peptide type B (NT-proBNP) might be both a more convenient measure of frailty and a predictor of overall survival (OS). Three-hundred and fifty-one consecutive symptomatic MM patients who were seen at Mayo Clinic within 30 days of diagnosis and who had blood stored were eligible. Data from the first visit was abstracted and used to calculate an ADL, CCI, and measure the NT-proBNP level. The best cutoff of NT-proBNP predicting OS was 300 ng/L. Variables predictive for OS were ECOG-PS, age, CCI, ADL, ISS, revised-ISS, and NT-proBNP. On multivariate analysis age ≥70, PS ≥2, and NT-proBNP ≥300 were independent predictors of survival. Patients were assigned a score of 1 for each of these variables, creating stages I-IV with scores of 0-3 points, respectively. The median OS from diagnosis was not reached, 58, 28, and 18 months (P < 0.0001), respectively. This frailty risk schema was independent of initial therapy and the revised-ISS. NT-proBNP is a useful predictor of survival independent of age and PS. It is a widely available biomarker that could be added to the panel of laboratory tests of newly diagnosed MM patients and serve as a simple and objective tool of determining frailty in clinical practice. Am. J. Hematol. 91:1129-1134, 2016. © 2016 Wiley Periodicals, Inc.

Induction therapy pre-autologous stem cell transplantation in immunoglobulin light chain amyloidosis: a retrospective evaluation.

There is no consensus on whether patients with immunoglobulin light chain amyloidosis (AL) should receive induction therapy prior to an autologous stem cell transplant (ASCT). This study investigated the relationships between baseline bone marrow plasmacytosis (BMPC), cardiac staging, and pre-transplant induction in AL patients. All patients who received ASCT for AL within 12 months of diagnosis were included. Patient characteristics and outcomes were abstracted. Univariate and multivariate modeling was performed. Among 415 AL patients, 35% had induction prior to ASCT. Post-ASCT hematologic CR plus VGPR rates were significantly higher in those with baseline BMPC ≤ 10% compared to BMPC >10% (58% versus 40%, P = 0.0013). Significant risk factors for lack of attainment of CR included attenuated dose melphalan conditioning, baseline BMPC > 10%, no induction, and male gender. The 5-year OS for the entire group was 65%. On multivariate analysis, risk factors for inferior OS included no induction therapy, advanced AL amyloid staging, BMPC > 10%, attenuated conditioning melphalan dose, and male gender. Patients with Mayo 2012 stage I-II patients with BMPC ≤ 10%, who comprised 56% of the ASCT population fared exceedingly well regardless of whether or not they received induction therapy with a 5-year OS of 81 to 83%. Induction therapy pre-ASCT may improve outcomes among AL patients due to a rapid reduction of toxic light chains or alternatively by elimination of less fit patients by "testing" their ability to tolerate chemotherapy. Prospective studies will be required to sort out these and other questions. Am. J. Hematol. 91:984-988, 2016. © 2016 Wiley Periodicals, Inc.

Predictors of early response to initial therapy in patients with newly diagnosed symptomatic multiple myeloma.

Response to therapy in newly diagnosed symptomatic multiple myeloma (NDMM) can impact long-term outcomes. It is not clear if baseline laboratory parameters can predict an early, deep response. Totally 1,304 patients with NDMM seen between 2001 and 2013 at Mayo Clinic Rochester were studied. The association between baseline laboratory parameters and early, deep response defined as a very good partial response or better (VGPR+) within four cycles of treatment was investigated. Multivariable logistic regression was used to assess the associations between the parameters of interest and response. Multivariable proportional hazards regression was used to assess the association between response and overall survival. In the entire cohort, greater absolute free light chain (FLC) differences (OR 2.38, 95% CI 1.48-3.82), younger age (OR 2.18, 95% CI 1.28-3.71), lower hemoglobin (OR 1.68, 95% CI 1.12-2.54), and IgA myeloma (OR 1.66, 95% CI 1.10-2.51) were associated with increased odds of achieving VGPR+ after four cycles. Among patients receiving novel agents in general and immunomodulators in particular, these effects were more pronounced. In patients receiving proteasome-inhibitors, higher creatinine (OR 3.83, 95% CI 1.37-10.1), lower calcium (OR 3.37, 95% CI 1.36-8.35), and greater absolute FLC differences (OR 2.50, 95% CI 1.10-5.71) were associated with better response. In a landmark analysis at 4 months from diagnosis, achieving VGPR+ was associated with decreased risk of subsequent mortality (HR 0.69, 95% CI 0.53-0.86). In summary, several parameters were associated with an early, deep response to treatment, revealing distinct sets of predictors for immunomodulator- and proteasome-inhibitor-containing regimens. Achieving VGPR+ after four cycles translated into increased overall survival.

Outcomes of patients with multiple myeloma refractory to standard dose vs low dose lenalidomide.

Refractoriness to lenalidomide is an important factor determining the choice of therapy at first relapse in multiple myeloma (MM). It remains debatable if resistance to lenalidomide varies among MM refractory to standard doses vs low dose maintenance doses. In this study, we assessed the outcomes with subsequent therapies in patients with MM refractory to standard dose vs low dose lenalidomide. We retrospectively reviewed all patients with MM at our institution who received first line therapy with lenalidomide containing regimens, and assessed progression free survival (PFS) and overall survival for these patients for second line therapy, and with lenalidomide retreatment. For second line therapy, we found no difference in the PFS between standard dose refractory and low dose refractory groups (median PFS 14 months vs 14 months, p = 0.95), while the PFS for both these groups was inferior to the not refractory group (median PFS 30 months, p < 0.001 for both pairs). Similar trends were seen among these groups on lenalidomide retreatment, and on multivariable analysis. These data suggest that refractoriness to lenalidomide is not dose dependent, and definition of lenalidomide refractoriness should not depend on the dose of lenalidomide to which the disease was considered refractory.

The impact of Post-Transplant doxycycline in AL amyloidosis - updated results after Long-Term follow up.

INTRODUCTION: The current treatment paradigm of AL amyloidosis lacks effective fibril-directed therapies. Doxycycline has been shown to have anti-fibril properties in preclinical models. In 2012, we reported that posttransplant prophylaxis with doxycycline was associated with improved survival compared to penicillin in patients with haematologic response. We provide here updated results after long-term follow up. METHODS: We included 553 patients who underwent transplant between July 24th, 1996, and June 24th, 2014. Doxycycline 100 mg daily was used for prophylaxis in patients with penicillin allergy; since 2013, doxycycline was used as the standard for prophylaxis. Prophylaxis was typically continued for a year after transplant. RESULTS: The median follow-up from transplant was 12.7 years. Doxycycline was used for prophylaxis in 33% of patients; the rest received penicillin. The median time to next treatment was 6.0 (95%CI; 4.4-8.8) years and 6.0 (95%CI; 4.9-7.1) years in the doxycycline and penicillin groups, respectively (p = .89). The median overall survival was 12.0 (95%CI: 11.0-19.6) years and 11.0 (95%CI: 9.6-12.7) years in the 2 groups, respectively (p = .17). There was a minimal trend towards improved survival with doxycycline among patients with ≥ very good partial response and among patients with organ response that was not statistically significant. CONCLUSION: After long-term follow-up, there is no clear evidence to support benefit of doxycycline in the post-transplant setting.