Mahindra, Anuj

PURPOSE Observation is the current standard of care for smoldering multiple myeloma. We hypothesized that early intervention with lenalidomide could delay progression to symptomatic multiple myeloma. METHODS We conducted a randomized trial that assessed the efficacy of single-agent lenalidomide compared with observation in patients with intermediate- or high-risk smoldering multiple myeloma. Lenalidomide was administered orally at a dose of 25 mg on days 1 to 21 of a 28-day cycle. The primary end point was progression-free survival, with disease progression requiring the development of end-organ damage attributable to multiple myeloma and biochemical progression. RESULTS One hundred eighty-two patients were randomly assigned—92 patients to the lenalidomide arm and 90 to the observation arm. Median follow-up is 35 months. Response to therapy was observed in 50% (95% CI, 39% to 61%) of patients in the lenalidomide arm, with no responses in the observation arm. Progression-free survival was significantly longer with lenalidomide compared with observation (hazard ratio, 0.28; 95% CI, 0.12 to 0.62; P = .002). One-, 2-, and 3-year progression-free survival was 98%, 93%, and 91% for the lenalidomide arm versus 89%, 76%, and 66% for the observation arm, respectively. Only six deaths have been reported, two in the lenalidomide arm versus four in the observation arm (hazard ratio for death, 0.46; 95% CI, 0.08 to 2.53). Grade 3 or 4 nonhematologic adverse events occurred in 25 patients (28%) on lenalidomide. CONCLUSION Early intervention with lenalidomide in smoldering multiple myeloma significantly delays progression to symptomatic multiple myeloma and the development of end-organ damage.

Abstract Abstract 532 Primary Plasma cell leukemia (PCL) is a rare plasma cell disorder characterized by an aggressive clinical course. The efficacy of autologous and allogeneic HCT in PCL is uncertain due to the small number of patients that have been reported in the literature. To determine the potential for long-term disease control using HCT in PCL, we performed a retrospective review of 160 patients with primary PCL who received autologous (n=107), allogeneic (n=52) or syngeneic (n=1) HCT and were reported to the CIBMTR between 1995 and 2006. Kaplan–Meier analysis was used for overall survival (OS) and progression free survival (PFS). Cumulative incidence estimates of non-relapse mortality (NRM), relapse, acute and chronic GVHD were calculated. Median age at the time of autologous HCT was 57 years (range, 32-74 years) and allogeneic HCT was 48 years (range, 24-62 years). Median time from initial treatment to autologous HCT was 7 months and allogeneic HCT was 6 months. At the time of transplant, in the autologous HCT group, 19% patients were in complete remission, 56% in partial remission and 1% had relapsed/progressive disease; in the allogeneic HCT group, 17% were in complete remission, 46% in partial remission and 10% had relapsed/progressive disease. In the allogeneic HCT group, 83% of the patients received myeloablative conditioning regimens and 17% received nonmyeloablative/reduced-intensity conditioning. The rate of acute GVHD was 35% (95% confidence interval [CI], 22%-49%) and the rate of chronic GVHD at 3 years was 27% (95% CI, 13%-40%). After a median follow-up of 38 months, 20 of the 52 patients (38%) are alive in the allogeneic HCT group and 68 of the 107 pts (64%) are alive in the autologous HCT group (Figure 1). Progressive disease accounted for 38% of the deaths in the allogeneic HCT group and 86% of the deaths in the autologous HCT group. The outcomes are summarized in table 1. The remarkable overall survival of patients after autologous HCT in this analysis is noteworthy and indicates that autologous HCT is a safe and acceptable treatment option for patients with primary PCL. Although relapse rates are lower, allogeneic HCT carries a much higher risk of NRM and should be considered primarily in the context of a clinical trial. Disclosures: Lonial: Celgene: Consultancy; Millennium: Consultancy, Research Funding; BMS: Consultancy; Novartis: Consultancy; Gloucester: Research Funding.

Abstract Abstract 4217 Background: AHCT improves survival (OS) in newly diagnosed MM patients (pts) in large randomized trials. These trials have limited eligibility to younger, healthier pts. Selection of older pts and those with co-morbid illness for AHCT is problematic. HCT-CI, originally developed as predictor of post-allogeneic transplant outcomes, maybe valuable in stratifying risk of transplant related mortality (TRM) risk and OS in the AHCT setting. We investigated the relative impact of HCT CI along with other patient and MM related variables on outcomes after AHCT in a large cohort of transplant recipients. Methods: Outcomes of 1156 MM pts receiving AHCT after high dose Melphalan (MEL) between 2007 and 2010 reported to the CIBMTR (Center for International Blood and Marrow Transplant Research) were analyzed. HCTCI scores and individual comorbidities were prospectively reported at time of AHCT. Median follow up of survivors was 26 month. The impact of HCTCI and other potential prognostic factors including Karnofsky performance status (KPS) on OS were studied in multivariate Cox regression models. Results: HCTCI score was 0, 1, 2, 3, >3 in 42%, 18%, 13%, 13% and 14% respectively. Most common co-morbidities included pulmonary, diabetes, obesity, psychiatric, cardiac, renal and prior solid tumor. Using consolidated HCTCI scores, patients were stratified initially into 3 risk groups – HCTCI 0 (42%) vs. HCTCI 1–2 (32%) vs. HCTCI >2 (26%). Males and Caucasians were more likely to have greater HCTCI score. Higher HCTCI was associated with lower KPS <90 (33% in HCTCI 0 cohort vs. 50% in HCTCI >2). HCTCI score >2 was associated with MEL dose reduction to 140 mg/m2 (22% vs. 10% in score 0 cohort). Cytogenetic risk and MM related factors were not correlated with HCTCI. TRM at 12 month was 2%, 2%, and 3% for 3 risk groups. With extremely few TRM events, multivariate analysis did not suggest an impact of HCTCI. OS was 95%, 92%, 92% at 1 year and 87%, 81%, 80% at 2 year, respectively. OS was inferior for HCTCI >2 cohort (RR of death 1.48, p=0.02) and HCTCI cohort 1–2 (RR 1.37, p=0.04) compared with HCTCI 0 cohort. There was no significant difference in OS between HCTCI >2 vs. HCTCI 1–2 (p=0.64). Therefore the latter 2 groups were combined as the HCTCI >0 cohort [N=667] and compared with HCTCI=0 [N=489] in multivariate models. HCTCI >0 predicted inferior OS (RR of death= 1.41, p=0.01). Other significant predictors of inferior survival were KPS <90 (RR of death 1.61, p<0.01), IgA subtype (RR 1.64, p<0.01), >1 pretransplant regimen (RR 1.47, p<0.01), resistant MM at AHCT (RR 1.78, p<0.01). Major cause of death in both groups was progressive MM. Conclusion: In clinical practice, higher HCTCI score was associated with MEL dose reduction. Mortality after AHCT is predominantly related to MM progression/relapse with low incidence of TRM. Higher HCTCI scores were independently associated with inferior OS. KPS remains an important tool for risk stratification. Disclosures: No relevant conflicts of interest to declare.

Abstract Abstract 591 Background: Survival of patients with MM has improved over the past two decades, in part due to the use of AHCT. Increasingly, second primary malignancies (SPMs) are observed in MM survivors. Determining the baseline incidence and risk factors associated with SPMs after AHCT is important to assess risk and to evaluate the risk-benefit ratio of newer therapies. Methods: We analyzed the incidence of SPMs in 3784 MM patients receiving (“upfront”) AHCT for MM within 18 months of diagnosis between 1990 and 2010 and reported to the CIBMTR. Cumulative incidence rates of SPMs were estimated taking into account the competing risk of death. For each transplant recipient, the number of person-years at risk was calculated from the date of transplantation until date of last contact, death, or diagnosis of SPM, whichever occurred first. Incidence rates for all invasive cancers in the general population were obtained from the SEER database. Age-, sex-, and race- specific incidence rates for overall SPMs and particular anatomical sites were applied to the appropriate person-years at risk to compute the expected numbers of cancers. Observed–to –expected (O/E) ratios were calculated, and Poisson distribution 99% confidence intervals (CIs) were generated. Poisson regression model was used to analyze risk factors for overall SPMs and AML/MDS. Results: Pre-transplant therapy included novel agents in 56% including thalidomide (35%), lenalidomide (9%), bortezomib (16%) or their combinations (11%). Majority (80%) received high dose melphalan conditioning. Post-transplant maintenance therapy included thalidomide (16%), lenalidomide (8%), bortezomib (9%) and interferon (6%). Median follow-up of survivors was 52 months (range 3 to 192 months).With 12707 person years of follow up, 153 new malignancies were reported with a crude rate of 1.2 SPM per 100 person years of follow up. Observed/Expected [O/E] ratio for all SPMs was 0.99 (99% CI, 0.80–1.22). Cumulative incidence of SPM overall was 2.48% (95% CI, 1.96–3.05) at 3 years and 6.0% (95% CI, 4.96–7.10) at 7 years [Figure 1]. Individual SPMs observed significantly more frequently than expected are summarized in Table 1. The cumulative incidence of MDS/AML was 0.5% (95% CI, 0.28–0.78) at 3 years and 1.3 (95% CI, 0.85– 1.9%) at 7 years. Majority had MM progression prior to diagnosis of SPM (65 of 102 patients overall and 15 of 23 patients for MDS/AML). In multivariate analysis, significant risk factors for development of SPMs included: obesity [Hazard ratio = HR 1.89(95%CI, 1.21–2.93), p=0.0047 for BMI>30 vs. BMI<25], older age: [HR10.53 (95%CI, 1.46–75.82), p=0.0195] for 60–69 year olds and HR14.4 (95%CI, 1.89–109.75), p=0.01 for 70+ year olds compared to the 18–39 year old group. Specific conditioning regimens did not correlate with the risk of SPM. The low number of MDS/AML (33 events out of 3784 cases) limited the power of multivariate analysis. Increasing age was significantly associated with development of MDS (HR10.77, (95%CI,92.09–55.51), p=0.004 for 70+ year old vs. 40–49 year olds). Conclusion: In this large cohort of AHCT recipients for MM, the incidence of MDS/AML, melanoma and other skin cancers was significantly higher compared to age and sex matched general population. However the overall risk of SPM was similar to that expected for age and sex matched population. It was also similar to the placebo arms of recent reports by McCarthy Pl et al and Attal M et al (N Engl J Med. 10; 366(19):1770–91). Lenalidomide (8%) or thalidomide maintenance (16%) used in a small subset of patients with comparatively short follow up, was not associated with risk of SPM in the analysis of the overall cohort. Disclosures: Gale: Celgene: Employment. Brandenburg:Celgene: Employment, Equity Ownership. Lonial:Millennium, Celgene, Novartis, BMS, Onyx, Merck all Consultancy. Krishnan:Celgene and Millennium: Consultancy, Speakers Bureau. Dispenzieri:Celgene and Millennium: Research Funding. Hari:Celgene: Consultancy, Honoraria.