Citations 81

Utility of Stem Cell Collection in Anticipation of Future Need for Autologous Stem Cell Transplant in Follicular Lymphoma Patients

Blood | October 12, 2019 | Volume: 118 | Issue: 21 | Pages: 1926-1926

10.1182/blood.v118.21.1926.1926

Abstract Abstract 1926 Background: Follicular lymphoma (FL) is the second most common non Hodgkin lymphoma in the United States, comprising up to 30% of all non Hodgkin lymphomas. Typically an indolent disease, relapses are common. High dose therapy followed by autologous stem cell transplant is an option that has shown to produce prolonged progression-free and relapse-free survival in patients who relapse. Adequate bone marrow reserve for peripheral stem cell mobilization has been shown to be adversely effected by prior regimens such as fludarabine and radioimmunotherapy. Concerns regarding stem cell mobilization at the point of relapse have led some to collect stem cells early in the course of disease to allow for potential subsequent transplant after relapse. Recent advances in stem cell mobilization have resulted in a 3% collection failure rate for lymphoma patients at the point of planned transplant at our institution versus a historical rate of up to 30%. We studied the utilization of stem cells collected for potential future use in FL patients in remission or prior to therapy at the point of relapse or progression in order to determine the utility of this approach. Methods: Record review of patients diagnosed with FL through the Mayo Clinic Tumor Registry and the Mayo Clinic Lymphoma Data Base who had cryopreserved stem cells for potential future transplant at relapse. Cost of stem cell storage at our institution was reviewed as was the subsequent use of the collected cells. Results: 73 patients with FL had stem cells collected and stored. 37 (51%) were collected prior to a double dose yttrium-90 (90Y) ibritumomab tiuxetan trial for relapsed lymphoma as required by the study. The median age at collection of this group was 56 years (range 28–70). Stem cells remain in storage for a median of 44 months (range 8–119). The median cost of cryopreservation and storage is $4,094 based on the median storage time of 44 months (range $3,628 to 5,065) with a collection cost of $3,524.20 and an annual storage fee of $155.39. This does not include the cost of filgrastim for mobilization, nor line placement. At 5 years, 60% of the cells were not utilized, and at 10 years, 56% of the cells were not utilized. 36 (49%) of the total number of patients were not part of the double dose 90Y ibritumomab tiuxetan trial, but were collected in remission for possible future use or in the setting of relapsed, progressed or transformed disease for potential future transplant. Five of these patients required the use of plerixafor for adequate mobilization. The median age at collection of this group was 47 years (range 24–76). Stem cells remain in storage for a median of 39 months (range 2–128). The median cost of cryopreservation and storage is $4,029 based on the median storage time of 39 months (range $3,550 to 5,182) with a collection cost of $3,524.20 and an annual storage fee of $155.39. This does not include the cost of filgrastim or plerixafor for mobilization, nor line placement. At 5 years, 89% of these cells were not used, and at 10 years, 71% of cells were not used. Conclusion: The utilization of stem cells collected early in the course of FL patients is low, with the majority of cells not being utilized at 10 years. Given improved mobilization techniques resulting in 97% efficacy of stem cell collection at relapse, routine collection and storage of stem cells early in the course FL is not recommended. Disclosures: Micallef: Genzyme: Membership on an entity's Board of Directors or advisory committees, Research Funding.
Comparison of Troponin T and N-Terminal-Pro-Brain Natriuretic Peptides In Two Models of Treatment Related Mortality In AL Amyloidosis Patients Following Autologous Stem Cell Transplantation

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 3572-3572

10.1182/blood.v116.21.3572.3572

Abstract Abstract 3572 High dose melphalan and autologous stem cell transplantation (ASCT) is an effective treatment for light chain amyloidosis (AL) but high treatment related mortality (TRM) limits its use. Both cardiac troponin T (cTnT) and N-terminal-pro-brain natriuretic peptide (NT-pro-BNP) are sensitive predictors of high risk patients. Aim of this study is to compare two models of TRM, one using cTnT and the other BNP. Patients who underwent ASCT between 7/1996 and 7/2009 at the Mayo Clinic were analyzed retrospectively. Variables were chosen for ease of measurement and reproducibility thus echocardiographic parameters were excluded. Each additional risk factor must contribute to a significant increase in TRM. Also, since NT-pro-BNP and cTnT are already highly associated with mortality, the other risk factors must be independent predictors. Univariate analysis revealed serum albumin, B-2-microglobulin, cTnT, NT-pro-BNP, and uric acid were associated with TRM while age, sex, alkaline phosphatase, serum creatinine, CRP, proteinuria were not (Table 1). Multivariate analysis showed albumin and uric acid were independent risk factors to cTnT and NT-pro-BNP (Table 2). Of the 412 patients, 347 (8.9% TRM) could be evaluated by the cTnT, albumin and uric acid (TAU) model and 282 (9.2%) TRM could be evaluated by the NT-pro-BNP, albumin, uric acid (BAU) model. Both models showed increasing TRM with additional risk factors beyond 1 risk factor (Table 3 and 4). Albumin and uric acid were found to be significant contributors in both models. Patients with elevated cTnT alone had a 0% TRM vs 23.4% if they had 1 additional risk factor, p = 0.03. Similarly, TRM was 3.7% in patients with elevated NT-pro-BNP alone but 18.0% if they had 1 other risk factor, p = 0.05. NT-pro-BNP and cTnT could not be used in the same model because cTnT becomes non-significant. Both models were superior to visceral organ involvement which had TRM of 5.3% with 1, 9.2% with 2 and 16.7% with 3 organ involvement. Both models were also predictive of overall survival (Figure 1 and Figure 1b). Our results show that these models show that albumin and uric acid with either cTnT or NT-pro-BNP can accurately predict TRM in AL patients undergoing ASCT. Multivariate analysis shows that the NT-pro-BNP containing model may be superior since cTnT loses it significance when added to the model. Our results suggest these models could be very helpful in identifying high risk patients not suitable for ASCT. Figure 1a Overall survival evaluated by Kaplan-Meier method on 347 patients using the TAU model. Mortality increased significantly with the number of risk factors, p < 0.001. Solid line represents patients with 0 risk factors, dotted line represents patients with 1 risk factor, dashed line represents those with 2 risk factors and dotted dashed line represent those with 3 risk factors. Figure 1a. Overall survival evaluated by Kaplan-Meier method on 347 patients using the TAU model. Mortality increased significantly with the number of risk factors, p < 0.001. Solid line represents patients with 0 risk factors, dotted line represents patients with 1 risk factor, dashed line represents those with 2 risk factors and dotted dashed line represent those with 3 risk factors. Figure 1b Overall survival evaluated by Kaplan-Meier method on 282 patients using the BAU model. Overall survival was significantly longer in patients with less risk factors, p < 0.001. Solid line represents patients with 0 risk factors, dotted line represents patients with 1 risk factor, dashed line represents those with 2 risk factors and dotted dashed line represent those with 3 risk factors. Figure 1b. Overall survival evaluated by Kaplan-Meier method on 282 patients using the BAU model. Overall survival was significantly longer in patients with less risk factors, p < 0.001. Solid line represents patients with 0 risk factors, dotted line represents patients with 1 risk factor, dashed line represents those with 2 risk factors and dotted dashed line represent those with 3 risk factors. Table 1. Patient characteristics Control TRM p-value N 318 29 Age 58 (25–73) 55 (35–75) 0.54 Sex (male) 58.2% 72.4% 0.13 Albumin (g/dl) 2.7 (0.8–4.4) 2.2 (0.8–3.7) 0.02 Alkaline phosphatase (U/L) 89 (28–1014) 86 (31–1394) 0.22 b2m (mg/ml) 2.6 (1.0–35.1) 3.2 (1.3–15.2) 0.007 NT-pro-BNP (pg/ml) 564 (12–35000) 1661 (21–35001) 0.03 CRP (mg/L) 0.3 (0.01–16.6) 0.3 (0.05–3.2) 0.34 cTnT (ng/ml) 0.01 (0–1.0) 0.03 (0.01–0.22) <0.001 Scr (mg/dl) 1.1 (0.4–12) 1.2 (0.8–2.3) 0.09 Proteinuria (g/d) 3.4 (0.01–35.4) 5.1 (0.1–20.5) 0.10 Uric acid (mg/dl) 6.2 (1–14.8) 7.5 (3.7–13.2) 0.02 Organ Involvement 1 94.7% 5.3% 0.04 2 90.7% 9.3% 3 83.3% 16.7% Table 2. Multivariate analysis using proportional hazard model cutoffs >Risk Ratio >p-value Model TAU cTnT 0.04 ng/ml 2.78 0.01 Albumin 3.3 g/dl 3.11 0.03 Uric acid 8.5 mg/dl 2.69 0.02 Model BAU NT-pro-BNP 1270 pg/ml 3.77 0.003 Albumin 3.3 g/dl 3.53 0.04 Uric acid 8.5 mg/dl 3.11 0.03 Table 3. Model of cTnT, albumin and uric acid TAU Risk Factors n TRM p-value Risk Ratio 0 69 2.9% 1 205 5.9% 0.33 2 61 16.4% 0.009 2.98 3 12 41.7% 0.05 8.52 Table 4. Model of NT-pro-BNP, albumin and uric acid BAU Risk Factors >n >TRM >p-value >Risk Ratio 0 28 0% 1 161 5.6% 0.20 2 82 14.6% 0.02 2.7 3 11 45.5% 0.01 10.8 Disclosures: Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Lacy:Celgene: Research Funding.
Five-Year Follow-up of Randomized, Phase II Trial of Idiotype-Pulsed Dendritic Cell Vaccine with Adjuvant Cytokines In Plateau Phase and Post-Transplant Multiple Myeloma

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 1958-1958

10.1182/blood.v116.21.1958.1958

Abstract Abstract 1958 Vaccines may offer additional benefit as consolidation therapy after plateau phase or autologous stem cell transplant (ASCT) for multiple myeloma (MM). We have reported previously the results of another phase II trial showing that using APC8020 (Mylovenge™) after ASCT improved the overall survival (OS 5.3 yrs, 95% CI 4.0 yrs – NA) compared to ASCT alone (3.4 yrs, 95% CI 2.7 – 4.6 yrs; p = 0.02; Lacy, AJH (84): 799). We now report the results from a randomized, phase II trial using the same vaccine plus adjuvant cytokines in MM patients in plateau phase after either chemotherapy or ASCT. Twenty patients were enrolled between 2001 and 2003 and were randomized to receive APC8020 and adjuvant cytokine of either interferon-g (IFNg, arm A, n = 10) or interleukin-2 (IL2, arm B, n = 10). Each cycle of treatment included five days of daily subcutaneous injections of either IFNg (106 IU, arm A) or IL2 (200 mg, arm B) followed by APC8020 injection. Each patient received a cycle of treatment every 2 weeks for 4 cycles. One patient in each arm was in plateau phase post-chemotherapy. Time from diagnosis to treatment was 11.9 mos for the patient in arm A and 16.2 mos for arm B. Time to progression (TTP) was 3.7 and 68 months respectively the patient in arm A and B. Both patients were alive at five years. For the 9 post-ASCT patients in each arm, no statistically significant differences were seen in the baseline characteristics between the 2 arms. The median time from diagnosis to treatment was 15.4 months. No grade 4 or 5 adverse events (AEs) were reported. Two patients in each arm had grade 3 AE, including lymphopenia, thrombocytopenia, hemorrhage, infection, and fatigue. One patient in arm B had grade 3 autoimmune disorder that was deemed possibly related to study treatment. The most common AEs were grade 1 fatigue (n = 7) and anemia (n = 5) in arm A and grade 1 anemia (n = 7) and injection site reaction (n = 5) in arm B. The median TTP was 9.3 months (95% CI: 3.9 – 19.3 months) for arm A and 6.6 months for arm B (95% CI: 6.3 – 29.6 months) with no statistically significant difference between the two arms (p = 0.89). The median OS had not been reached for either arm; the 5-year OS rate was 67% and 56% for arms A and B respectively (p = 1.0). Interestingly, similar to our previous study where TTP was not different while OS was improved with vaccine, when we compared the clinical outcome for all patients in this vaccine trial to that of 78 matched control patients who only received ASCT during the same time frame, we did not see significant improvement in TTP (Figure 1). However, the 5-year overall survival for all patients in this trial is significantly improved at 71% (95%CI: 51–96%) compared to ASCT control patients (41%, 95% CI: 31 – 54%; p = 0.03; Figure 1). This trial suggests improved OS with vaccine plus cytokine. It is possible that modulation of patients’ immunity may help them live longer with multiple myeloma. Further investigation is needed to compare the approach in this trial with dendritic cell vaccine alone to better understand optimal strategy for vaccine therapy in MM. Figure 1. Kaplan-Meier curves for time to progression and overall survival Figure 1. Kaplan-Meier curves for time to progression and overall survival Disclosures: Dispenzieri: Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding. Lacy:Celgene: Research Funding.
Transplantation for Immunoglobulin Light Chain Amyloidosis. A Statistical Analysis of Factors Predicitng Outcome In Over 400 Patients

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 3557-3557

10.1182/blood.v116.21.3557.3557

Abstract Abstract 3557 Introduction: Autologous stem cell transplantation for patients with amyloidosis results in high reported hematologic and organ response rates compared with conventional chemotherapy. Patients: Four-hundred and thirty-four patients have undergone transplantation between March 8, 1996, and April 13, 2010 Table 1. Clinical parameters seen in patients with amyloid are given in Table 2. The overall day-100 mortality seen in this group of patients is 44 of 434 patients (10%). Results: The most important determinant of outcome is stage defined by BNP and troponin levels. Figure 1 demonstrates the survival for patients for all 3 cardiac stages. Troponin <.035; NT-proBNP <332. Stage 1 both low, Stage 3 both elevated. The survival of all patients based on whether they achieved a complete response, a partial response (>50%), or no response was analyzed. Median survival has not been reached for the complete response group, is 107 months for the partial response group, and is 32 months for the no response group (p<0.0001). Figure 2, divides the patients at the median dFLC level of 13.5 mg/dL demonstrating that for patients with a higher level of free light chain, the median survival is 87.6 months and has not been reached for those with a lower level of free light chain. A proportional hazards model for variables that impact on survival was done in all patients, and the only relevant predictor of outcome was stage (p<0.0001). When the same analysis was performed using a landmark of 6 months, the only predictor of outcome was stage (p=0.0005). When best response was incorporated into the landmark model, it was the strongest predictor of survival. The amyloid stage predicted survival (p= 0.0005), and the best response to therapy (p <0.0001). When the same analysis was performed in the entire group of 434, stage and best response each remained significant (p<0.0001). Discussion: There is a high response rate associated with high-dose therapy that was not observed in the melphalan and prednisone era. For eligible patients who can be transplanted safely, high-dose melphalan is an effective therapy for many patients with amyloidosis. Best response and stage at diagnosis are the best predictors of overall survival. Disclosures: Lacy: Celgene: Research Funding. Dispenzieri:Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Kumar:Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding.
Peripheral Blood Stem Cell Collection In Patients Undergoing Induction Therapy with Lenalidomide Based Regimens: Failure Rates and Salvage Approaches

Blood | October 12, 2019 | Volume: 116 | Issue: 21 | Pages: 2253-2253

10.1182/blood.v116.21.2253.2253

Abstract Abstract 2253 Background: Lenalidomide based combinations are among the most common initial therapies for myeloma. Previous studies have suggested that lenalidomide therapy can result in suboptimal stem cell collection in patients eligible to undergo autologous stem cell transplantation, especially older patients after prolonged exposure to the drug. Many salvage approaches are used when attempting repeat stem cell collection in this patient group. Patients and Methods: Two hundred twenty four patients who underwent stem cell collection following lenalidomide-dexamethasone induction from July 2004 and December 2009 were included in the current analysis. Data pertaining to the duration of lenalidomide therapy, stem cell mobilization regimen, and the collection yields were collected from the medical records. Results: The median age at mobilization was 60.6 years (range; 29, 76) and 136 (60%) were male. There were a total of 245 collection attempts from among 224 patients, 21 (9.8%) patients attempting to remobilize after failing to collect the desired numbers of stem cells at the first attempt. We first analyzed the results of the initial collection attempt. The median duration of lenalidomide therapy prior to stem cell collection was 4 months (range; 1, 26). The mobilization strategies were GCSF (Granulocyte Colony Stimulating Factor) alone in 151 (67%) patients, cyclophosphamide (CTX) followed by GCSF in 29 (13%) patients, and GCSF plus AMD3100 in 44 (20%) patients. Among those receiving AMD3100, it was added either due to peripheral blood CD34 cell count not reaching the threshold for initiation of harvest or for poor first day CD34 cells collection in 34 patients and given in a planned fashion in 10 patients. Overall 15 patients (7%) failed to reach the peripheral CD34 cell counts required to initiate apheresis, and among those starting apheresis 6 patients failed to collect at least 2 million CD34 cells/kg; a cumulative failure rate of 9%. Another 18 (8%) patients failed to collect at least 4 million CD34 cells /kg. The CD34 cells yield on day 1, the total yield, number of collections, the average daily yield and the percentage of the targeted cells collected for each mobilization strategy including failure rates are detailed in the table. Twenty-one patients reattempted stem cell mobilization; including 14 that failed a first attempt and 7 did who not achieve the intended goal even though they collected more than 2 million CD34 cells/kg. The mobilization regimens were GCSF alone, CTX + GCSF, GCSF + GM-CSF (Granulocyte Macrophage Colony Stimulating Factor) and GCSF + AMD in 5, 8, 3, and 4 patients respectively. All patients collected at least 2 million CD34 cells /kg and 14 patients (70%) collected more than 4 million CD34 cells /kg. The median CD34 cells collected with the second attempt was 5.4 million/kg (rang; 2, 19.5) bringing the median total collection for these 21 patients to 9.6 million/kg (2.6-19.6). Overall, of the 224 patients studied, all but the 6 patients who failed initially and did not attempt a second collection collected at least 2 million CD34 cells /kg and 197 (88%) collected at least 4 million CD34 cells/kg. Conclusion: While the overall failure rate of stem cell collection in patients receiving initial therapy with lenalidomide is 10%, a risk adapted approach of adding AMD3100 appear to decrease the risk of failure. However, majority of patients failing a stem cell harvest attempt can be salvaged with a second collection allowing these patients to proceed to a stem cell transplant if desired. Disclosures: Gertz: Celgene: Honoraria; Millenium: Honoraria, Membership on an entity's Board of Directors or advisory committees; Genzyme: Research Funding. Lacy: Celgene: Research Funding. Dispenzieri: Celgene: Honoraria, Research Funding; Binding Site: Honoraria. Micallef: Genzyme: Membership on an entity's Board of Directors or advisory committees. Kumar: Celgene: Consultancy, Research Funding; Millennium: Research Funding; Merck: Consultancy, Research Funding; Novartis: Research Funding; Genzyme: Consultancy, Research Funding; Cephalon: Research Funding.
Predicting Poor Peripheral Blood Stem Cell Mobilization in Multiple Myeloma (MM) Using Initial Peripheral CD34 Counts: Developing Target-Based Cut-Points for Early Intervention.

Blood | October 12, 2019 | Volume: 114 | Issue: 22 | Pages: 3231-3231

10.1182/blood.v114.22.3231.3231

Abstract Abstract 3231 Poster Board III-168 Background Peripheral blood stem cells (PBSC) are the preferred graft type for autologous stem cell transplantation (ASCT) and mobilization is typically done using growth factor (GF) alone or a combination of chemotherapy (CTX) and GF. The success of mobilization is influenced by several factors such as prior therapy and mobilization strategy. Patients (Pts) failing to mobilize successfully often have GF dose increased and if unsuccessful, mobilization reattempted with chemotherapy + GF or G-CSF (Granulocyte Colony-Stimulating Factor) + GM-CSF (Granulocyte-Macrophage Colony-Stimulating Factor). More recently, plerixafor, a CXCR4 inhibitor, has been found to enhance G-CSF based collection allowing potential early intervention in poor mobilizers. However, this approach requires valid cut-points for peripheral CD34 counts (pCD34) for cost efficient use. Methods We studied 910 first time, G-CSF based PBSC mobilizers with MM (565; 62%), or light chain amyloidosis (345; 38%). Salvage attempts were excluded, as were first attempts using CTX+GCSF, plerixafor or GF combinations. Sensitivity-specificity analysis (ROC) was used to define ideal cut-points for predefined outcomes. We used a CD34 yield of 2 million/kg as the minimum required collection and 4 million/kg as the ideal collection for this analysis. Our current practice is to initiate collection at a pCD34 of 10/uL. Results We first determined the best day 1 pCD34 cutoff for being able to collect at least 2 million/kg PBSC to be 9.2/uL. Among those with ≥9.2/uL, only 1.6% failed to collect at least 2 million compared to 27% among the rest (P < 0.001). These numbers were 1.7% and 25% respectively using the traditional cutoff of 10/uL. We then examined how the pCD34 on day 2 predicted collection, among those failing to reach the current threshold of 10/uL. Among this group, a pCD34 on day 2 of 8/uL was the best cutoff to predict a collection of 2 million/kg. Among those with >8/uL, only 9% failed to collect at least 2 million compared to 48% among the rest (P < 0.001). Among those with day 1 pCD34 < 10, 65% achieved a count of 8/uL on day 2. We then examined what pCD34 on day 1 can best predict a pCD34 ≥ 8 on day 2 and found this to be 5/uL. Among those with day 1 pCD34 ≥ 5/uL, 92% reached day 2 pCD34 ≥ 8 compared to 36% among the rest (P < 0.001).We then determined cutoffs based on ideal targets using only those patients achieving pCD34 count > 10/uL by day 2, since these patients would have started collection without any change in the mobilization technique. We used a maximum of 5 collections to achieve the goal as being ideal, taking into account the most commonly used practice of collecting during weekdays. We examined cutoffs both for a target of 4, 8 and 12 million/kg for one, two or three transplants respectively. Among those with a day 1 or day 2 pCD34 > 10/uL 98% collected 4 million/kg in 5 collections. The best day 1 or day 2 pCD34 predicting a 8 million/kg yield in 5 collections was 21.4/uL and a 12 million/kg yield was 27.9/uL. Among those with day 1or 2 pCD34 ≥ 21.4/uL, 90% collected 8 million compared to 54% among those with pCD34 < 21.4/uL. Similarly, among those with day 1 or 2 pCD34 ≥ 27.9/uL, 79% reached 12 million in ≤ 5 days compared to 17% among those with pCD34 < 27.9/uL (P < 0.001).Finally we examined if poor collection on first day, despite a pCD34 > 10 predicts for poor overall yield. A ratio of day 1 collection (million/kg) to pCD34 day 1 or 2 < 5×104 was highly predictive of failure to get eventual yield of 2 million/kg, with 38% below the cutoff failing to reach the goal compared to 2% for those above the cutoff. Conclusions This study provides an estimate of optimal pCD34 count thresholds for early identification of patients at high risk of collection failure. It is reasonable to use the first or second day pCD34 count, since a substantial proportion of patients will achieve the threshold value by day 2 and have similar outcome as those reaching the threshold by day 1. Based on the results here, interventions such as plerixafor can be considered if pCD34 count is < 5/uL on day 1 or < 9/uL by day 2, to achieve the minimum collection of 2 million/kg. However, in order to achieve the ideal targets, a higher threshold should be considered and the recommendation would be 17/uL, and 28/uL for target of 8 or 12 million respectively. Finally, identification of poor mobilizers after start of collection potentially provides another time point for early intervention, and this needs to be prospectively studied. Disclosures Micallef: Genzyme: Research Funding. Gertz:Genzyme: Research Funding. Kumar:Celgene,Genzyme,Millenium,Novartis,Bayer,: Honoraria, Research Funding.
A Risk Adapted Approach Utilizing Plerixafor in Autologous Peripheral Blood Stem Cell Mobilization.

Blood | October 12, 2019 | Volume: 114 | Issue: 22 | Pages: 3211-3211

10.1182/blood.v114.22.3211.3211

Abstract Abstract 3211 Poster Board III-148 Although autologous stem cell transplantation (ASCT) has become standard of care for many patients with hematologic malignancies, many patients fail to collect a minimum number of CD34 + stem cells to support high dose chemotherapy and ASCT. Recently, plerixafor, a CXCR4 antagonist, was FDA approved for use in combination with G-CSF for autologous peripheral blood stem cell mobilization in patients with NHL or Multiple Myeloma. In February 2009, we commenced a risk adapted approach to the utilization of plerixafor. The study was restricted to patients mobilized with GCSF alone and patients undergoing chemotherapy primed PBSC mobilization were excluded. Peripheral blood stem cell mobilization was commenced with G-CSF at 10 mcg/kg/day. On day 4, a peripheral blood (PB) CD34 count was measured. For patients whose PB CD34 was ≥10/μL, apheresis was commenced the following morning. For patients whose PB CD34 was <10/μL, it was measured again on day 5; if ≥10/μL then apheresis was commenced the following morning. If PB CD34 was <10/μL on day 5, plerixafor (0.24 mg/kg sc) was administered on the evening of day 5 and apheresis was commenced the following day (Group A). In addition, during apheresis, for patients whose collection yield was < 0.5 × 106 CD34/kg, in the absence of instrument failure or problems with the collection procedure, plerixafor was added (Group B). Morning administration of G-CSF and evening dosing of plerixafor continued daily until apheresis was complete. From February to July 2009, 174 mobilization attempts occurred; 27 with chemotherapy and 147 with cytokines alone. The 147 pts who underwent mobilization with cytokines alone are presented here. The underlying diagnosis was as follows: Myeloma 61 pts, NHL 54 pts, Amyloid 17 pts, Hodgkin 10 pts, POEMS 4 pts and 1 pt with a solid tumor. For the entire group the median number of CD34 cells collected was 5.5 × 106 CD34/kg (range 0.1-17). The median number of apheresis was 3 (range 1-12). 67 patients (46%) received plerixafor; 37 patients started plerixafor during mobilization (Group A) and 30 patients during collections due to a poor yield (Group B). 12 pts of the 37 received plerixafor on day 4 because of prior mobilization failure or high risk of mobilization failure and are included in Group A. Table 1 outlines the details of mobilization and collection by groups. By disease category, of the 61 patients with MM, 28 (46%) received plerixafor (8 Group A and 20 Group B). Median apheresis in all the MM pts was 2 (range 1-12) with a total of 6.8 × 106 CD34/kg (2.2-16.7). In the 54 NHL pts, 32 (59%) received plerixafor (24 Group A and 8 Group B). Median apheresis for all pts with NHL was 3 (range 1-7) with a total of 4.6 × 106 CD34/kg (range 0-11.4). Overall, only 7 of 147 (5%) mobilization attempts failed to achieve a minimum of 2 × 106 CD34/kg. This compares to a 22% failure rate prior to institution of this risk adapted approach. In conclusion, implementing this risk adapted approach allows poor mobilizers to be identified promptly and for plerixafor to be initiated during mobilization and collection, thereby reducing the number of mobilization failures. In patients who predictably would not have successful collection based on a PB CD34 <10/μL, addition of plerixafor results in a majority of patients achieving an adequate collection. This risk adapted approach may be more cost effective than reattempting mobilization after a prior failure or utilizing combination G-CSF and plerixafor for upfront mobilization. Table 1. Mobilization and Collection data. All patients N=147 Group A1 N=37 Group B2 N=30 No Plerixafor N=80 PB CD34 day 4 Median 11 0 7 19 Range 0-331 0-7 0-32 0-331 PB CD34 day 5 Median 10 4.5 12 15 Range 0-51 2-9 11-23 9-51 Apheresis Yield Median 5.5 4.4 6.0 6.2 Range 0.1-17 3.1-12.7 3.0-12.2 2-17 Number of Apheresis Median 3 3 5 2 Range 1-12 1-7 4-12 1-8 Days of Plerixafor Median n/a 3 2 n/a Rang 1-7 1-8 1 Group A – Plerixafor initiated prior to apheresis 2 Group B – Plerixafor initiated during apheresis Disclosures No relevant conflicts of interest to declare.
Implications of Body Weight Calculations for Autologous Peripheral Blood Stem Cell Transplantation.

Blood | October 12, 2019 | Volume: 108 | Issue: 11 | Pages: 5445-5445

10.1182/blood.v108.11.5445.5445

Abstract Background: Obesity is a prevalent health problem and significant heterogeneity is seen in the body weight and BMI among adult patients undergoing autologous stem cell transplantation (SCT). At least two critical steps of the SCT are influenced by the body weight. Stem cell collection targets are usually determined based on the actual body weight and conditioning chemotherapy doses are usually determined based on corrected ideal body weight. One could hypothesize that since the stem cells home to bone marrow, the ideal body weight (IBW) being based on the height may be a better indicator of the stem cell numbers required rather than the actual body weight (ABW). Since chemotherapy doses are calculated based on corrected ideal body weight, and the volume of distribution is higher in obese patients, these patients may have decreased drug exposure and hence a higher risk of progression. Methods: We retrospectively evaluated the engraftment kinetics and response outcome of 306 SCTs done at our institution between March 1998 and October 2001. These included patients who had undergone SCT for multiple myeloma (46%), NHL (34%), HD (6%) and AL amyloidosis (14%). Body weight, height, stem cell dose and engraftment data was obtained from medical records. The stem cell dose received was calculated based on their ABW as well as IBW and correlated with the time to white cell and platelet engraftment. We also evaluated the effect of BMI on the progression free survival after the stem cell transplant using various cut offs. Results: The mean (range) for the ABW, IBW and BMI were 46.6 kg to 189 Kg; 45.5 kg to 94 kg; and 17.5 to 55.8 respectively. Using logistic regression, we estimated the ability of CD34 cell dose by actual and ideal body weight to predict the likelihood of platelet engraftment (50,000) by day 21 post transplant. The coefficients using both the doses were very similar (.391 for ideal and 0.361 for actual). Using Receiver operating characteristic analysis (ROC analysis); we determined the stem cell dose cutoff that best predicted for failure to engraft neutrophils by 21 days post transplantation, median CD34 dose by ABW of 3.6 million/Kg and by IBW of 4.2 million/Kg. Similarly, for failure to engraft platelets by day 30 the cutoffs were 2.89 million/Kg by actual weight and 3.77 million/kg by ideal weight. Among the individuals with actual body weight more than 25% of ideal body weight (n=122, 40%), we calculated the optimal total CD34 dose required and compared to the actual dose infused using both the cutoff sets (286 million vs. 446 million, P < 0.001 using ANC cutoff and 251 million vs. 446 million using the platelet cutoff, P < 0.001). We then examined the effect of BMI on progression free and overall survival from transplant. The progression free and overall survival post transplant was similar for patients with BMI over 30 kg/m2 compared to those below this cutoff. There was no difference when patients with myeloma or lymphoma were studied separately. Conclusion: This study, as in previous studies, confirms that stem cell dose determined on the basis of ideal body weight is comparable to that by actual body weight in terms of engraftment kinetics. In patients significantly above the ideal body weight, it is reasonable to use a target based on ideal body weight which will allow for collection of less numbers of CD34 cells, thus conserving resources. Among patient undergoing stem cell transplant, the practice of using corrected ideal body weight does not appear to compromise the outcome of stem cell transplant.
Clinical Impact and Resource Utilization After Stem Cell Mobilization Failure in Patients with Multiple Myeloma and Lymphoma.

Blood | October 12, 2019 | Volume: 114 | Issue: 22 | Pages: 2142-2142

10.1182/blood.v114.22.2142.2142

Abstract Abstract 2142 Poster Board II-119 High-dose chemotherapy in conjunction with autologous SCT is the preferred treatment of relapsed Hodgkin disease and non-Hodgkin lymphoma and newly diagnosed multiple myeloma. Failure to achieve optimal stem cell mobilization results in multiple subsequent attempts, which consumes large amounts of growth factors and potentially requires antibiotics and transfusions. We retrospectively reviewed the natural history of stem cell mobilization attempts at our institution from 2001 through 2007 to determine the frequency of suboptimal mobilization in patients with hematologic malignancy undergoing autologous transplant and analyzed the subsequent resource utilization in patients with initially failed attempts. Of 1,775 patients undergoing mobilization during the study period, stem cell collection (defined by the number of CD34+ cells/kg) was “ optimal” (≥5×106) in 53%, “low” (≥2 to 5×106) in 25%,“ poor” (<2×106) in 10%, and “failed” (<10 CD34+ cells/mL) in 12%. In the 47% of collections that were less than optimal, increased resource consumption included increased use of growth factors and antibiotics, subsequent chemotherapy mobilization, increased transfusional support, more apheresis procedures, and more frequent hospitalization. Other costs often omitted include the need for hospitalization, which was seen in 5% to 11% of the patients in our study. Parenteral antibiotics were needed when fever developed in 7% of patients with Hodgkin disease, 4% with non-Hodgkin lymphoma, and 24% with multiple myeloma who underwent mobilization using a chemotherapy pulse. When stem cell mobilization was not immediately optimal, subsequent attempts to mobilize failed completely in 3 of 42 patients (7%) with Hodgkin disease (3% of the original Hodgkin disease cohort), 56 of 157 (36%) with multiple myeloma (6% of the original myeloma cohort), and 50 of 328 (15%) with non-Hodgkin lymphoma (7% of the original non-Hodgkin lymphoma cohort). These usually unappreciated costs of stem cell mobilization failure highlight the need for more effective mobilization strategies. Disclosures: Gertz: genzyme: Research Funding.
Cost-Effectiveness Of Antithrombin Repletion In Adult Patients With Acute Lymphoblastic Leukemia (ALL) Treated With Asparaginase-Containing Combination Chemotherapy; A Single Center Experience

Blood | October 12, 2019 | Volume: 122 | Issue: 21 | Pages: 1732-1732

10.1182/blood.v122.21.1732.1732

Abstract Introduction L-asparaginase therapy results in systemic depletion of antithrombin (AT) and fibrinogen (FG), resulting in thrombotic (TE) and hemorrhagic events (HE). Prophylactic correction of coagulation disturbances have been inconclusive with regard to cost effectiveness, and specifically cost effectiveness of antithrombin concentrate (ATC) replacement has not been evaluated. (Abbott et al, 2009, Mitchell et al, 2003). Currently, AT repletion is recommended for levels less than 60%. (Stock et al, 2012) Several treatment protocols with distinctly different L-asparaginase (LAS) or pegaspargase (PEG) doses complicate the frequency and intensity of ATC replacement. We carried out this study to evaluate the cost effectiveness of ATC replacement, based on our institutional practice. Methods This single center, retrospective, observational study was approved by the Institutional Review Board and conducted at Mayo Clinic, Rochester, MN. Consecutive adult patients with a confirmed diagnosis of ALL receiving LAS or PEG between January 2000 and October 2012 were evaluated. Patients with hereditary or acquired thrombophilias or pre-existing TE or HE, were excluded. Per institutional guidelines, ATC was administered if levels were less than 70%. The Centers for Medicare & Medicaid (CMS) single drug historical pricing guide was utilized for 2000-2004. ATC cost beginning January 1, 2005, was derived from the CMS average sales price, reported quarterly. To adjust for price differences due to regimen utilization trends, each dose was also calculated at the final 2012 cost of 3.05/unit. ATC repletion practices and estimated expenditures were compared between regimens. Results Fifty four patients were treated with LAS or PEG containing regimens. Of these, 47 (87%) received ATC. Twenty-eight patients received LASP, 22 received PEGASP and 4 received both. Distribution across protocols was; CALGB 9111 (n=20, Larson et al, 1998), E2993 (n=13, Goldstone et al, 2008), C10403 (n=9, NLM: NCT00558519), CCG 1941 (n=7, Gaynon et al, 2006) and Augmented HyperCVAD (n=5, Faderl et al, 2005). PEG and LAS dosing schemes are outlined in table 1 . LAS doses were converted to PEG upon specific protocol revision or at discontinuation of LAS availability in 2012. Regimens specified a dose cap with the exception of C10403. A total of 399 LAS and PEG doses resulted in 378 instances of ATC repletion. The reimbursement price of ATC in 2000 was estimated at 1.50/unit U.S. dollars (USD) and 3.04/unit USD by the fourth quarter of 2012. The total estimated average sales price was 2,471,745 USD over the study period. C10403 resulted in the highest median number of PEG doses per patient (n = 5) and a median of 17 ATC doses per dose of PEG. This resulted in C10403 being the most expensive regimen with the median expense for ATC replacement being 118,064 USD (chart 1). This conclusion was also seen after comparing different regimens using the most recent 2012 cost estimates. The overall incidence of TE or HE was 17% and equally distributed between regimens (please see accompanying abstract). Conclusions Repletion of ATC in patients receiving asparaginase containing chemotherapy regimens is very expensive and continues to add to costs at many centers, without clear benefit, especially with regards to TE and HE. A prospective, randomized, multicenter clinical trial looking to answer this question is the need of the hour. Disclosures: No relevant conflicts of interest to declare.