Stem Cell Transplant Comorbidity Index Research Articles

Total Body Irradiation and Fludarabine with Post-Transplantation Cyclophosphamide for Mismatched Related or Unrelated Donor Hematopoietic Cell Transplantation

Allogeneic hematopoietic cell transplantation (HCT) remains the sole curative treatment for most patients with hematologic malignancies. A well-matched donor (related or unrelated) remains the preferred donor for patients undergoing allogeneic HCT; however, a large number of patients rely on alternative donor choices of mismatched related (haploidentical) or unrelated donors to access HCT. In this retrospective study, we investigated outcomes of patients who underwent mismatched donor (related or unrelated) HCT with a radiation-based myeloablative conditioning MAC regimen in combination with fludarabine, and post-transplantation cyclophosphamide (PTCy) as higher-intensity graft-versus-host disease (GVHD) prophylaxis. We retrospectively assessed HCT outcomes in 155 patients who underwent mismatched donor HCT (related/haploidentical versus unrelated [MMUD]) with fractionated-total body irradiation (fTBI) plus fludarabine and PTCy as GVHD prophylaxis at City of Hope from 2015 to 2021. Diagnoses included acute lymphoblastic leukemia (46.5%), acute myelogenous leukemia (36.1%), and myelodysplastic syndrome (6.5%). The median age at HCT was 38 years, and 126 patients (81.3%) were an ethnic minority. The Hematopoietic Stem Cell Transplantation Comorbidity Index was ≥3 in 36.1% of the patients, and 29% had a Disease Risk Index (DRI) of high/very high. The donor type was haploidentical in 67.1% of cases and MMUD in 32.9%. At 2 years post-HCT, disease-free survival (DFS) was 75.4% and overall survival (OS) was 80.6% for all subjects. Donor type did not impact OS (hazard ratio [HR], .72; 95% confidence interval [CI], .35 to 1.49; P = .37) and DFS (HR, .78; 95% CI, .41 to 1.48; P = .44), but younger donors was associated with less grade III-IV acute GVHD (HR, 6.60; 95% CI, 1.80 to 24.19; P = .004) and less moderate or severe chronic GVHD (HR, 3.53; 95% CI, 1.70 to 7.34; P < .001), with a trend toward better survival (P = .099). The use of an MMUD was associated with significantly faster neutrophil recovery (median, 15 days versus 16 days; P = .014) and platelet recovery (median, 18 days versus 24 days; P = .029); however, there was no difference in GVHD outcomes between the haploidentical donor and MMUD groups. Nonrelapse mortality (HR, .86; 95% CI, .34 to 2.20; P = .76) and relapse risk (HR, .78; 95% CI, .33 to 1.85; P = .57) were comparable in the 2 groups. Patient age <40 years and low-intermediate DRI showed a DFS benefit (P = .004 and .029, respectively). High or very high DRI was the only predictor of increased relapse (HR, 2.89; 95% CI, 1.32 to 6.34; P = .008). In conclusion, fludarabine/fTBI with PTCy was well-tolerated in mismatched donor HCT, regardless of donor relationship to the patient, provided promising results, and increased access to HCT for patients without a matched donor, especially patients from ethnic minorities and patients of mixed race.

The predictive value of HCT-CI and CCI comorbidity indices in predicting survival and mortality before allogeneic stem cell transplantation in acute leukemia patients: A single-centre experience

Objective: Acute leukemia often involves comorbidities, impacting treatment decisions and patient outcomes. Clinicians commonly use the Charlson Comorbidity Index (CCI) and the Hematopoietic Stem Cell Transplantation Comorbidity Index (HCT-CI) to assess their influence. However, their effectiveness in predicting survival and non-relapse mortality (NRM) in acute leukemia patients under 65 undergoing allogeneic stem cell transplantation remains unclear. Patients and Methods: We conducted a retrospective single-center analysis on adults diagnosed with acute myeloid leukemia (AML) or acute lymphoblastic leukemia (ALL). The study included 35 patients, comprising 16 AML and 19 ALL cases. Patients were categorized based on age-adjusted HCT-CI and CCI scores. Results: The 2-year NRM rate was determined to be 51.4%. Statistical analysis found no significant associations between age-adjusted CCI (p=0.217) and age-adjusted HCT-CI (p=0.102) with NRM. However, median overall survival significantly varied based on risk levels (p=0.003), HCT-CI groups (p=0.009), and CCI groups (p=0.011). Conclusion: Using age-adjusted HCT-CI and CCI for comorbidity scoring in initial assessment of acute leukemia patients and those under 65 shows promise. However, these indices were ineffective in predicting NRM, emphasizing the importance of considering other significant pre-transplant factors like genetic risk, conditioning regimens, and donor type.

Adjusting diffusing capacity for anemia in patients undergoing allogeneic HCT: a comparison of two methodologies

BackgroundDiffusing capacity (DLCO) measurements are affected by hemoglobin. Two adjustment equations are used: Cotes (recommended by ATS/ERS) and Dinakara (used in the hematopoietic stem cell transplantation comorbidity index [HCT-CI]). It is unknown how these methods compare, and which is better from a prognostication standpoint. Study designThis is a retrospective cohort of 1273 adult patients who underwent allogeneic HCT, completed a pre-transplant DLCO and had a concurrent hemoglobin measurement. Non-relapse mortality was measured using competing risk analysis. ResultsPatients had normal spirometry (FEV1 99.7% [IQR: 89.4–109.8%; FVC 100.1% [IQR: 91.0-109.6%] predicted), left ventricular ejection fraction (57.2[6.7]%) and right ventricular systolic pressure (30.1[7.0] mmHg). Cotes-DLCO was 85.6% (IQR: 76.5-95.7%) and Dinakara-DLCO was 103.6% (IQR: 90.7-117.2%) predicted. For anemic patients (Hb<10g/dL), Cotes-DLCO was 84.2% (IQR: 73.9–94.1%) while Dinakara-DLCO 111.0% (97.3–124.7%) predicted. Cotes-DLCO increased HCT-CI score for 323 (25.4%) and decreased for 4 (0.3%) patients. Cotes-DLCO was superior for predicting non-relapse mortality: for both mild (66-80% predicted, HR 1.55 [95%CI: 1.26-1.92, p < 0.001]) and moderate (<65% predicted, HR 2.11 [95%CI: 1.55-2.87, p<0.001]) impairment. In contrast, for Dinakara-DLCO, only mild impairment (HR 1.69 [95%CI 1.26-2.27, p < 0.001]) was associated with lower survival while moderate impairment was not (HR 1.44 [95%CI: 0.64-3.21, p = 0.4]). In multivariable analyses, after adjusting for demographics, hematologic variables, cardiac function and FEV1, Cotes-DLCO was predictive of overall survival at 1-year (OR 0.98 [95%CI: 0.97-1.00], p = 0.01), but Dinakara-DLCO was not (OR 1.00 [95%CI: 0.98-1.00], p = 0.20). ConclusionThe ERS/ATS recommended Cotes method likely underestimates DLCO in patients with anemia, whereas the Dinakara (used in the HCT-CI score) overestimates DLCO. The Cotes method is superior to the Dinakara method score in predicting overall survival and relapse-free survival in patients undergoing allogeneic HCT.

Outcome improvement over time in reduced intensity conditioning hematopoietic transplantation: a 20-year experience.

The current study includes all consecutive patients (N = 484) who received a reduced-intensity conditioning regimen (RIC) allogeneic hematopoietic stem cell transplantation in our center from 1999 to 2020. Conditioning regimens were based on fludarabine with melphalan or busulfan, with low-dose thiotepa and pharmacological GVHD prophylaxis consisted of cyclosporine A (CsA)-methotrexate (MTX)/mofetil (MMF) (n = 271), tacrolimus-sirolimus (n = 145), and post-transplantation cyclophosphamide (PTCy)-tacrolimus (n = 68). The median time of overall follow-up in survivors was 8years (1-22years) and was at least 3years in all three GVHD prophylaxis groups. Thirty-three percent had a high or very high disease risk index, 56% ≥ 4 European bone marrow transplantation risk, and 65% ≥ 3 hematopoietic stem cell transplantation comorbidity index score-age score. Neutrophil and platelet engraftment was longer for PTCy-tacro (p 0.0001). Cumulative incidence of grade III-IV aGVHD was 17% at 200days, and that of moderate-severe cGvHD was 36% at 8years. GVHD prophylaxis was the only prognostic factor in the multivariable analyses for the development of aGVHD and moderate-severe cGVHD (p 0.0001). NRM and relapse incidences were 29% and 30% at 8years, while OS and PFS rates were 43% and 39% at 8years. At 3years, OS was highest in the PTCy-tacro group (68%) than in the tacro-siro (61%) and CsA-MTX/MMF (49%) cohorts (p < 0.01). In the three groups, respectively, the 200-day incidence of grade III-IV aGvHD (6% vs. 12% vs. 23%) and 3-year moderate-severe cGVHD (8% vs. 40% vs. 38%) were lower in the PTCy cohort. These better outcomes were confirmed in multivariable analyses. Based on our recent results, the PTCy could be considered as a real GvHD prophylaxis in the RIC setting due to improve best 3-year GvHD and survival outcomes.

Comparing Arsenic-Containing Qinghuang Powder and Low-Intensity Chemotherapy in Elderly Patients with Acute Myeloid Leukemia.

To compare the clinical effect of arsenic-containing Qinghuang Powder (QHP) and low-intensity chemotherapy (LIC) in treatment of elderly acute myeloid leukemia (eAML) patients. Clinical data of 80 eAML patients treated at Xiyuan Hospital of China Academy of Chinese Medical Sciences from January 2015 to December 2020 were retrospectively analyzed. The treatment scheme was designed by real world study according to patients' preference, and patients were divided into a QHP group (35 cases) and a LIC group (45 cases). The median overall survival (mOS), 1-, 2-, and 3-year OS rates, and incidence of adverse events were compared between the two groups. The mOS of 80 patients was 11 months, and the 1-, 2-, and 3-year OS rates were 45.51%, 17.96%, and 11.05%, respectively. The QHP and LIC groups demonstrated no significant difference in mOS (12 months vs. 10 months), 1- (48.57% vs. 39.65%), 2- (11.43% vs. 20.04%), and 3-year OS rates (5.71% vs. 13.27%, all P>0.05). Moreover, the related factors of mOS demonstrated no significant difference in patients with age>75 years (11 months vs. 8 months), secondary AML (11 months vs. 8 months), poor genetic prognosis (9 months vs. 7 months), Eastern Cooperative Oncology Group performance status score ⩾ 3 (10 months vs. 7 months) and hematopoietic stem cell transplant comorbidity index ⩾ 4 (11 months vs. 7 months) between the QHP and LIC groups (all P>0.05). However, the incidence of myelosuppression was significantly lower in the QHP group than that in the LIC group (28.57% vs. 73.33%, P<0.01). QHP and LIC had similar survival rates in eAML patients, but QHP had a lower myelosuppression incidence. Hence, QHP can be an alternative for eAML patients who do not tolerate LIC.

A Multicenter, Retrospective Study Evaluating Clinical Outcomes of Ruxolitinib Therapy In Heavily Pretreated Chronic GVHD Patients With Steroid Failure

Although ruxolitinib is emerging as the treatment of choice for steroid-refractory or -dependent chronic graft versus host disease (cGVHD) based on randomized control trial data, there is relatively little real-world data published on ruxolitinib for this indication. We wanted to evaluate the real-world efficacy and safety of ruxolitinib in cGVHD patients who have failed any previous systemic therapy for cGVHD. We retrospectively evaluated the efficacy of ruxolitinib in 115 heavily pretreated patients with steroid-refractory or -dependent chronic GVHD across 5 transplantation centers. The majority of the study population had severe cGVHD (60%) and received ruxolitinib at the fourth treatment line or beyond (82%, n = 96). The median duration of follow-up in this study population was 13 months. The overall response rate (ORR) was 48.6%, 54.9%, and 48.5% at 3, 6, and 12 months, respectively. Clinical benefit (an outcome metric combining ORR with steroid reduction) was observed in 58.7%, 64.8%, and 60.6% of patients at 3, 6, and 12 months, respectively. Approximately one third of patients (37.9%) were able to discontinue prednisone at 12 months, and 63.8% were able to taper prednisone to a daily dose <0.1 mg/kg at 12 months. Failure-free survival at 12 months was 64.6% (54.1%-73.2%). Multivariate analysis identified that patients with severe cGVHD were at a higher risk of failure because of a therapy switch, whereas a pretransplantation hematopoietic stem cell transplantation–comorbidity index score ≥ 3 was associated with a high risk of failure because of increasing risk of non-relapse mortality. Overall, this study demonstrates the therapeutic efficacy of ruxolitinib for cGVHD in a heavily pretreated real-world population.

The limited use of autologous hematopoietic stem cell transplant for fit older patients with multiple myeloma in India: a retrospective analysis

BackgroundMultiple myeloma (MM) predominantly affects older patients; many of whom do not undergo autologous hematopoietic stem cell transplant (AHSCT) despite the associated survival benefits. This study was conceived to investigate the patterns of AHSCT among MM patients with due regard to their age and standardized fitness assessments.MethodsFitness scores as per the hematopoietic stem cell transplant-comorbidity index (HSCT-CI) and risk scores as per the revised-myeloma comorbidity index (R-MCI) of MM patients treated between January 2017 and December 2019 were analyzed to assess fitness for AHSCT. Proportions of patients who underwent AHSCT were calculated with regard to age and fitness for AHSCT.ResultsOf the 81 eligible patient records with a median age of 62 years, the HSCT-CI classified 79.6% and 77.8% of patients aged ≤65 years and >65 years as AHSCT eligible (p 1). Using the R-MCI, 96.3% and 81.5% of patients aged ≤65 years and >65 years, respectively, were classified as eligible for AHSCT (p 0.0381). Overall, patients aged ≤65 years underwent AHSCT with a greater frequency compared to those aged >65years (38.9 vs. 14.8%, p 0.0402). Irrespective of the age group, there was a statistically significant difference (p 0.0167) in terms of survival which favored those who underwent AHSCT.ConclusionsBoth the HSCT-CI and the R-MCI revealed that nearly 80% of patients aged >65 years were fit enough to receive AHSCT. However, far fewer patients of this age group underwent AHSCT. We propose that the routine inclusion of objective fitness assessment could ensure that fit older patients undergo AHSCT and thus do not miss out on the benefits of the same.

Risk Factors for Catheter-Related Thrombosis in Multiple Myeloma Patients Undergoing Autologous Stem Cell Transplantation.

Background and Objectives: Cancer associated thrombosis (CAT) is a common complication of neoplasms. Multiple myeloma (MM) carries one of the highest risks of CAT, especially in the early phases of treatment. Autologous stem cell transplantation (ASCT) as the standard of care in transplant-eligible patients with MM carries a risk of catheter-related thrombosis (CRT). The aim of this study was identification of the risk factors of CRT in MM patients undergoing ASCT in 2009–2019. Materials and Methods: We retrospectively analyzed patients with MM undergoing ASCT. Each patient had central venous catheter (CVC) insertion before the procedure. The clinical symptoms of CRT (edema, redness, pain in the CVC insertion area) were confirmed with Doppler ultrasound examination. We examined the impacts of four groups of factors on CRT development: (1) patient-related: age, gender, Body Mass Index (BMI), obesity, Charlson comorbidity index, hematopoietic stem cell transplantation comorbidity index, renal insufficiency, and previous thrombotic history; (2) disease-related: monoclonal protein type, stage of the disease according to Salmon–Durie and International Staging System, number of prior therapy lines, and MM response before ASCT; (3) treatment-related: melphalan dose, transplant-related complications, and duration of post-ASCT neutropenia; (4) CVC-related: location, time from placement to removal. Results: Symptomatic CRT was present in 2.5% (7/276) of patients. Univariate analysis showed an increased risk of CRT in patients with a catheter-related infection (OR 2.4, 95% CI; 1.109–5.19, p = 0.026), previous thrombotic episode (OR 2.49, 95% CI; 1.15–5.39, p = 0.021), previous thrombotic episode on initial myeloma treatment (OR 2.75, 95% CI; 1.15–6.53, p = 0.022), and gastrointestinal complications of ASCT such as vomiting and diarrhea (OR 3.87, 95% CI; 1.57–9.53, p = 0.003). In multivariate analysis, noninfectious complications were associated with higher CRT incidence (OR 2.75, 95% CI; 1.10–6.19, p = 0.031). Conclusions: The incidence of symptomatic CRT in ASCT in MM was relatively low. Previous thrombotic events, especially during the induction of myeloma treatment, increased CRT risk during ASCT. Dehydration following gastrointestinal complications may predispose to higher CRT incidence.

Validation of a Predictive Model for Survival in Patients with Acute Myeloid Leukemia and Myelodysplastic Syndrome Receiving Hematopoietic Stem Cell Transplantation

▪IntroductionAllogeneic hematopoietic stem-cell transplantation (AHSCT) is an effective treatment for patients with high-risk or relapsed acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). Several factors are known to influence survival post-transplant. Our group developed a model to predict survival in a small number of patients with AML/MDS using 3 disease (cytogenetics and disease status at transplant) and patient-related [Hematopoietic stem cell transplant comorbidity index (HCT-CI)] variables (Bachegowda et al.Blood.2017) . This model effectively stratified AML/MDS patients into 3 risk groups with very different survival. Here we aim to validate this model in a large cohort of AML/MDS patients receiving AHSCT with various donor types.MethodsA total of 934 patients with AML/MDS consecutively treated at the University of Texas MD Anderson Cancer Center were included in this analysis. Donors were HLA matched related (n=377, 40%), matched unrelated (n=416, 45%) mismatched unrelated (n=68, 7%) and T-cell replete haploidentical transplants (n=73, 8%). The median age was 53 years (range 18-65 years). Cytogenetics data at diagnosis was available in 920 patients and was favorable, intermediate and adverse-risk in 340 (37%), 517 (56%) and 63 (7%), respectively. Five hundred and forty patients (58%) were in first or second complete remission (CR1/2). The hematopoietic stem cell transplant comorbidity index (HCT-CI) was available in 914 patients and the median score was 2 (range 0-17). The sources of hematopoietic stem cells were peripheral blood for 586 patients (63%) and bone marrow for 348 patients (37%). Seven hundred and eighty patients (84%) received myeloablative-conditioning chemotherapy.ResultsPatients were stratified into 3 risk groups according to the previously published model: 1) low-risk group (patients in CR1/2 with intermediate/favorable risk cytogenetics, irrespective of HCT-CI (HCT-CI did not impact survival in this group) (n=351), 2) intermediate-risk group (patients beyond CR1/2 and/or with adverse-risk cytogenetics and HCT-CI score ≤4) (n=412), and 3) high-risk group (patients with at least one negative prognostic factor - beyond CR1/2 and/or with adverse-risk cytogenetics and a HCTCI score >4) (n=155).Median follow up duration for 436 survivors was 48 months. For the whole group, the 5-year progression-free survival (PFS), treatment-related mortality (TRM) and relapse rate were 39%, 21% and 39%, respectively. TRM at 5 years for low-risk group was 17%, for the intermediate-risk group was 18% (HR [95% CI] 1.12 [0.79-1.59]; P=0.52), and for the high-risk group was 40% (3.24 [2.26-4.64]; P<0.0001), respectively, whereas cumulative incidence of relapse at 5 years was 24% for low-risk, 52% for intermediate-risk (2.86 [2.20-3.71]; P<0.0001) and 38% for the high-risk group (1.88 [1.34-2.63]; P<0.0001), respectively. In multivariable model, transplantation in >CR1/2 (2.84 [2.38-3.40]; P<0.0001), adverse cytogenetic risk (1.54 [1.29-1.83]; P<0.0001), males (1.23 [1.03-1.46]; P=0.022) were significantly associated with worse PFS while higher age-adjusted HCT-CI scores (1.20 [0.99-1.47]; P=0.06) approached significance. Other factors including conditioning intensity (1.02 [0.82- 1.29]; P=0.84, age (1.01 [1.00-1.01]; P=0.17) and donor type (haploidentical (1.2 [0.83-1.72]; P=0.33), matched unrelated (1.06 [0.88-1.28]; P=0.55) and mismatched unrelated donor (1.07 [0.76-1.50]; P=0.70) as compared with matched related donor) did not significantly influence PFS. Using our previously described predictive model, the patients separated in 3 risk groups with significantly different median PFS, which was not reached for the low-risk group, 9.2 months for the intermediate-risk group (2.4 [1.97-2.99]; P<0.0001), and 6.0 months for the high-risk group (3.3 [2.57-4.21]; P<0.0001), respectively. (Figures 1A and 1B)In conclusion, we were able to stratify allogeneic stem cell transplant patients in 3 risk groups based on a combination of disease (cytogenetics and disease status at transplant) and patient-related factors (HCT-CI) with significantly different survival. HCT-CI appears to have a much higher discriminatory impact in patients with higher risk disease (not in CR1/CR2 and/or adverse risk cytogenetics) compared with those in the lower risk group (CR1/CR2 and intermediate/favorable risk cytogenetics). [Display omitted] DisclosuresOran:AROG: Research Funding; Celgene: Research Funding; Astex: Research Funding. Khouri:Novartis: Research Funding.

Excessive Early Death after Intensive Chemotherapy for Acute Myeloid Leukemia Occurs in Patients over 65 Years with High Co-Morbidity, and in Patients over 50 Years with High Co-Morbidity When Postponed Early Death Is Included

Background Early death (ED) after intensive induction chemotherapy is defined as death by any cause occurring in the first 30 days after start of chemotherapy. ED significantly contributes to poor outcome in elderly acute myeloid leukemia (AML) patients. The presence of co-morbidity, as determined with the hematopoietic stem cell transplantation co-morbidity index (HCT-CI) has been shown to predict ED in patients >60 years, with HCT-CI scores of 0, 1-2 or ≥3 resulting in ED rates of 3%, 11% and 29%, respectively (Giles et al. BJH 2007). This makes the HCT-CI an ideal tool to distinguish elderly AML patients fit for intensive chemotherapy from those that may benefit more from less intensive alternative treatments.However, the number of studies on HCT-CI and ED risk are limited and have only reported on ED in relation to age as a categorical valuable (age below or over 55-60 years). Data on the usability of the HCT-CI for ED prediction in different age cohorts are not available. Therefore, we performed a retrospective study to assess the value of the HCT-CI in predicting ED in different age cohorts in order to improve treatment decision in AML.Methods We retrospectively analysed ED risk in relation to HCT-CI in different age cohorts in 260 AML patients treated with intensive chemotherapy at our institution between 2003 and 2015. Median age of the patients was 59 years (range 19-79). All patients received intravenous cytarabine, mostly continuously in a dose of 100-200 mg/m2 per day for 7-10 days, in combination with different anthracyclines.Results ED occurred in 17 patients (6.5%) after a median of 18 days (range 1-29) from start of chemotherapy. ED was low in patients <=50 years, irrespective of HCT-CI score. Only patients aged >65 years with a HCT-CI >=3 showed an excessive ED rate of 22%. All other patient cohorts showed moderately increased ED rates, never exceeding 10%.In addition to the 17 patients that died before day 30, another 11 patients without refractory disease died after day 30 before the second chemotherapy cycle. These were mainly patients aged 51-65 years that had been admitted to the Intensive Care, which had postponed their ED. By including postponed ED into ED, ED risk increased to 20% in patients aged 51-65 years with HCT-CI >=3. Mortality in patients with HCT-CI 0-2 remained maximally 10% in all age groups.Conclusion In our hands, only patients aged over 65 years with high co-morbidity (HCT-CI >=3) have an excessive risk for ED (>20%) when treated with intensive chemotherapy. In this patient group alternative therapies should be considered. Intensive care admission results in postponement of ED after day 30 in a considerable proportion of patients, especially in those aged 51-65 years. By including postponed ED (defined as death in remission after day 30 but before second induction) into ED, all patients aged over 50 years with high co-morbidity (HCT-CI >=3) show excessive risk for ED (>20%) when treated with intensive chemotherapy. DisclosuresNo relevant conflicts of interest to declare.

Pre- Transplant Ferritin Predicts Overall Survival and Non-Relapse Mortality in Patients Undergoing Allogeneic Hematopoietic Cell Transplantation for Myelofibrosis

Background: Elevated serum ferritin (SF) is common in patients with myelofibrosis (MF) given the frequent red-cell transfusion requirements and impaired iron metabolism. The dysregulation of iron metabolism is associated with increased hepcidin levels which predict for inferior survival in patients with MF (Pardanani et al AJH 2013). High pre-transplant SF negatively impacts overall survival and non-relapse mortality in patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) for hematological malignancies (Chee et al BMT 2017 &amp; Yan et al 2018). However, the impact of elevated pre-transplant SF specifically on post-alloHCT outcomes has not been described in MF. Methods: We conducted a retrospective study of patients with MF undergoing allo-HCT at Mayo clinic Rochester, Arizona, and Florida from January 1st 2012 - December 31st 2019. We abstracted demographic and outcome variables to evaluate the impact of pre-transplant ferritin levels on post-transplant outcomes. We used a Receiver Operand Characteristic Curve to identify a pre-transplant serum ferritin (SF) of ≥ 1,123 ng/mL as the cutoff which best correlated with poor survival. Results: We identified 67 patients with MF who underwent allo-HCT during the study period with readily available data. Patients with a pre-transplant ferritin ≥ 1,123 ng/mL (n=18) had a median age of 59.4 years and were predominantly male (n=9, 50%) with primary myelofibrosis (n=12, 67%), had a DIPSS-plus int-2 (n=10, 56%) and high (n=6, 33%) risk categories and received a reduced-intensity conditioning (n=14, 78%) from a matched-unrelated donor (n=7, 50%) Table1. Patients with SF ≥ 1,123 ng/mL had a worse overall survival (OS) (median OS= 12.64 months [95%CI=6.08-19.20 months] vs. not-reached (NR) p=0.001). Patients with elevated SF had an increased non-relapse mortality (NRM) rate at 6 months (16.7%, [95%CI=0.4-37.2%]) vs 8.2%,[95%CI= 2.6-18.1%] p=0.021) and 12 months (33.3% [95%CI=13.0-55.4%] vs 10.4% [95%CI=3.8-21.0%] p=0.021) Patients with ≥ 1,123 ng/mL SF had a non-statistically significant higher rate of acute graft-vs-host disease grades 3-4 (28% vs 12.2% p=0.13) but similar rates of moderate to severe chronic graft-vs-host disease (31% vs 28% p=0.78). In the univariate analysis, SF ≥1,123 ng/mL and a Hematopoietic stem cell transplant comorbidity index (HCT-CI) ≥3 were associated with an increased risk of mortality (Hazard ratio [HR]=4.18 [95%CI=1.64-10.62] p=0.003] and HR=4.42 [95%CI=1.70-11.46] p=0.003, respectively). Both retained significance in multivariate analysis SF ≥1,123 ng/mL (HR= 2.80 [95%CI= 1.0-7.6], p=0.04)] and HCT-CI score ≥ 3 (HR 3.10 [95%CI= 1.12-8.62, p=0.03]) after adjusting for age, DIPSS-plus score, conditioning regimen intensity, donor type, CMV risk, prior use of ruxolitinib, and ABO mismatch. We grouped the patients into low, intermediate and high risk categories using SF level and HCT-CI scores as detailed in Figure 1. The risk category based on SF and HCT-CI was statistically significant in impacting OS and NRM in this cohort. The 12 month OS rate was lower in the high risk category (44.4% [95%CI= 13.6%-71.9%]) when compared to the intermediate (64.6%, [95%CI=39.7%-81.3%]) and low risk (91.9%, [95%CI= 76.9%-97.3%], p=0.0002) categories. Similarly, the 12 month NRM rate was higher in the high risk category (44.4%, [95%CI=11.0%-74.2%]) when compared to the intermediate (25%, [95%CI=8.7%-45.5%]) and low risk (5.3% [95%CI=0.9%-15.9%], p=0.0046) categories. Conclusion: In patients undergoing allogeneic SCT for myelofibrosis, serum ferritin ≥ 1,123 ng/mL is a predictor of high NRM and inferior OS. Combining ferritin serum levels with HCT-CI may help in better patient selection for allo-HCT in MF population. Larger patient cohort is warranted to confirm our findings. Disclosures Kharfan-Dabaja: Daiichi Sankyo: Consultancy; Pharmacyclics: Consultancy. Shah:Dren Bio: Consultancy.

A Study Highlighting the Limited Use of Autologous Hematopoietic Stem Cell Transplant for Fit Elderly Patients with Multiple Myeloma in India

BACKGROUND Autologous Hematopoietic Stem Cell Transplant (AHSCT) remains an important treatment for multiple myeloma (MM) despite the continuous addition of novel agents into the therapeutic armamentarium. Since MM is predominantly a disease of the elderly, a significant proportion of patients do not undergo AHSCT due to 'a perceived lack of fitness'. This retrospective study evaluates the patterns of AHSCT in MM patients with regards to age and objective fitness assessment as per standardized indices. METHODS: Records of all MM patients treated at our institute from January 2017 till December 2019 were utilized to collect data regarding age, survival duration, risk scores as per the Revised-Myeloma Comorbidity Index (R-MCI) and fitness scores as per the Hematopoietic Stem Cell Transplant-Comorbidity Index (HSCT-CI). Patients with low and intermediate R-MCI risk scores were regarded as 'fit for AHSCT'. Patients with HSCT-CI categorizations of 'fit' and 'intermediate fit' were regarded as 'fit for AHSCT'. Proportions were compared using the Fisher-Exact-Test with a significance cut-off of p&amp;lt;0.05. Survival data were compared with the Log-Rank test. RESULTS: Out of the 81 patients, 54 (66.7%) were aged ≤65 years &amp; 27 (33.3%) &amp;gt;65 years. The R-MCI classified 96.3% and 81.5% of patients aged ≤65 years and &amp;gt;65 years as AHSCT eligible, respectively (p 0.0381). The HSCT-CI classified a similar proportion of patients aged ≤65 years and &amp;gt;65 years as AHSCT eligible (79.6% vs. 77.8%, p 1). However, patients aged ≤65 years were offered AHSCT more frequently than those &amp;gt;65 years (57.4% vs. 29.6%, p 0.0207). Those aged ≤65 years underwent AHSCT more frequently than those &amp;gt;65 years (38.9% vs. 14.8%, p 0.0402). (Panel A, Figure-1). Those who underwent AHSCT had greater median survival (MS) compared to those who did not undergo AHSCT (MS not reached vs. 36 months, p 0.0023) (Panel B, Figure 1). Those who were offered AHSCT had greater MS compared to those who were not offered AHSCT (MS not reached vs. 36 months, p 0.033) (Panel C, Figure 1). The MS of patients classified as fit and intermediate fit as per the HSCT CI was significantly better than that of those classified as 'unfit' (p 0.0362) (Panel D, Figure 1). The MS of patients classified by the R-MCI as low risk was significantly better than that of those classified as 'intermediate and high risk' (p 0.0253) (Panel E, Figure 1). When the MS of overall patients aged ≤65 years was compared to that of those aged &amp;gt;65 years, there was no significant difference with the MS not reached in either group (p 0.0875) (Panel F, Figure 1). When the survival curves of four groups (aged &amp;gt;65 years who underwent AHSCT, aged &amp;gt;65 years who did not undergo AHSCT, aged ≤65 years who underwent AHSCT, and those aged ≤65 years who did not undergo AHSCT) were compared, there was a statistically significant difference favouring those who underwent AHSCT irrespective of the age group (p 0.0167) (Panel G, Figure 1). Conclusions: Both the R-MCI and HSCT-CI revealed that approximately four out of five patients aged &amp;gt;65 years were AHSCT eligible. This analysis of the patterns of AHSCT for MM in our institution revealed a bias against those aged &amp;gt;65 years, with fewer patients of this age group being offered AHSCT. It would hence be prudent to perform objective fitness assessments using validated indices so as to ensure that every patient fit enough to benefit from an AHSCT receives the same irrespective of his/her age. While it is well known that treatment availability and affordability are two major reasons for low rates of AHSCT in Low &amp; Middle Income Countries (LMICs), it can be said from our data that physicians' bias against advanced age could be another factor. These results strongly suggest that use of AHSCT in fit elderly patients in LMICs may further improve outcomes. Figure Disclosures No relevant conflicts of interest to declare.

Quality of Life following Allogeneic Stem Cell Transplantation for Patients Age >60 Years with Acute Myelogenous Leukemia.

This study of patients with acute myelogenous leukemia (AML) age ≥60 years analyzed the association between patients' performance indices-Hematopoietic Stem Cell Transplantation Comorbidity Index (HCT-CI), Karnofsky Performance Score (KPS), and European Society for Blood and Marrow Transplantation (EBMT) risk score-before undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) and quality of life (QoL), quantified using the Functional Assessment of Cancer Therapy-Bone Marrow Transplant Scale (FACT-BMT), in the first year after allo-HSCT. Over a period of 7 years, 48 evaluable patients underwent reduced-intensity conditioning allo-HSCT. The median patient age was 65 years (range, 60 to 74 years), with 2-year and 5-year overall survival (OS) of 65.8% and 52.3%, respectively. A significant improvement across all QoL scores was observed over the 12 months post-HSCT. An HCT-CI of 0 was associated with improved general QoL (FACT-G) score at 6 months compared with patients with an HCT-CI of 1 to 2 (P= .032). At 12 months post-HSCT, a pretransplantation HCT-CI ≥3 was correlated with lower QoL scores across the domains (symptom-related QoL [FACT-TOI], P= .036; FACT-G, P= .05; BMT-related QoL [FACT-BMT], P= .036). A pretransplantation KPS score of 100 versus 80 to 90 was predictive of improved QoL at 6 months post-HSCT (FACT-TOI, P=.009; FACT-G, P= .001; FACT-BMT, P= .002) but not at 1 year post-HSCT. We demonstrate that KPS and HCT-CI can predict QoL in the early post-transplantation period, with a favorable overall survival in a selected cohort of AML patients age ≥60 years.

PS1247 EZH2 GAIN-OF-FUNCTION MUTATIONS ARE NOT ASSOCIATED WITH MORE FAVORABLE PROGNOSIS IN RELAPSED/REFRACTORY FOLLICULAR LYMPHOMA: A PRELIMINARY ANALYSIS ON 590 PATIENTS

Background: Haploidentical stem cell transplantation (Haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) represents a potential curative strategy for patients with Hodgkin lymphoma (HL) when a matched related or unrelated donor is not available1. While bone marrow (BM) was originally the preferred stem cell source, more recently peripheral blood stem cell (PBSC) is more often used. Some retrospective studies suggest that the risk to develop acute and chronic graft-versus-host-disease (GVHD) is higher with PBSC than BM, while PBSC may reduce the risk of relapse2. Aims: Here we analyzed the effect of stem cell source in 91 HL patients receiving Haplo-SCT with PT-Cy, with the aim to evaluate if the final outcome is modified by the use of PBSC or BM Methods: From April 2009 to January 2017, 91 consecutive patients with poor prognosis HL received a Haplo-SCT with PT-Cy either from a PBSC (n = 38) or BM (n = 53). The two cohorts were similar for most characteristics, but the PBSC group had more patients with an unfavorable hematopoietic stem cell transplant comorbidity index (HCT-CI) score ≥3 (p = 0.002) and had received a non myeloablative conditioning (NMAC; p = 0.001). Results: Cumulative incidence of neutrophil>500/ul at day +30 and of platelet >20000/ul at day +60 were 96% (95% CI: 89–98) and 96% (95% CI: 88–99), respectively, with no significant differences between the PBSC and BM cohorts. With a median follow-up of 22.8 months, there was no difference between PBSC and BM graft in terms of cumulative incidence of grade 2–4 acute GVHD (29% vs 21%, p = 0.3), grade 3–4 acute GVHD (3% vs 4%, p = 0.7) and moderate-severe chronic GVHD (9% vs 7%, p = 0.7). This was also confirmed by multivariate analysis (data not shown). In the whole population, the 2-year overall survival (OS), 2-year progression-free survival (PFS) and 1-year GVHD/relapse free survival (GRFS) rates were 67%, 58% and 58%, respectively. We observed a trend for improved OS (74% vs 62%, p = 0.07) and PFS (62% vs 56%, p = 0.1) for recipients of PBSC relative to BM cells, but pre-transplant disease status was the only significant variable by univariate analysis (Table I). By multivariate analysis, PBSC resulted a protective factor both for OS (HR: 0.29, p = 0.006), PFS (HR: 0.38, p = 0.001) and GRFS (HR: 0.44, p = 0.020). The other independent variables affecting the final outcome were pre-transplant disease status and hematopoietic cell transplant comorbidity index (HCT-CI) (Table I). Non-relapse mortality was not affected by graft source both by univariate and multivariate analysis, while pre-transplant disease status was the only variable affecting the chance of disease relapse.Summary/Conclusion: Overall these data suggest that PBSC is associated with better outcome, in terms of OS, PFS and GRFS, relative to BM cells as graft source for patients undergoing Haplo-SCT with PT-Cy. In addition, the risk of acute and chronic GVHD is not increased after PBSC relative to BM graft.

PS1246 GRAFT SOURCE AND PRE‐TRANSPLANT DISEASE STATUS ARE THE MAIN VARIABLES AFFECTING THE OUTCOME OF T CELL‐REPLETE HAPLOIDENTICAL TRANSPLANTATION WITH POST‐TRANSPLANT CYCLOPHOSPHAMIDE FOR HODGKIN LYMPHOMA

Background:Haploidentical stem cell transplantation (Haplo‐SCT) with post‐transplant cyclophosphamide (PT‐Cy) represents a potential curative strategy for patients with Hodgkin lymphoma (HL) when a matched related or unrelated donor is not available1. While bone marrow (BM) was originally the preferred stem cell source, more recently peripheral blood stem cell (PBSC) is more often used. Some retrospective studies suggest that the risk to develop acute and chronic graft‐versus‐host‐disease (GVHD) is higher with PBSC than BM, while PBSC may reduce the risk of relapse2.Aims:Here we analyzed the effect of stem cell source in 91 HL patients receiving Haplo‐SCT with PT‐Cy, with the aim to evaluate if the final outcome is modified by the use of PBSC or BMMethods:From April 2009 to January 2017, 91 consecutive patients with poor prognosis HL received a Haplo‐SCT with PT‐Cy either from a PBSC (n = 38) or BM (n = 53). The two cohorts were similar for most characteristics, but the PBSC group had more patients with an unfavorable hematopoietic stem cell transplant comorbidity index (HCT‐CI) score ≥3 (p = 0.002) and had received a non myeloablative conditioning (NMAC; p = 0.001).Results:Cumulative incidence of neutrophil&gt;500/ul at day +30 and of platelet &gt;20000/ul at day +60 were 96% (95% CI: 89–98) and 96% (95% CI: 88–99), respectively, with no significant differences between the PBSC and BM cohorts. With a median follow‐up of 22.8 months, there was no difference between PBSC and BM graft in terms of cumulative incidence of grade 2–4 acute GVHD (29% vs 21%, p = 0.3), grade 3–4 acute GVHD (3% vs 4%, p = 0.7) and moderate‐severe chronic GVHD (9% vs 7%, p = 0.7). This was also confirmed by multivariate analysis (data not shown). In the whole population, the 2‐year overall survival (OS), 2‐year progression‐free survival (PFS) and 1‐year GVHD/relapse free survival (GRFS) rates were 67%, 58% and 58%, respectively. We observed a trend for improved OS (74% vs 62%, p = 0.07) and PFS (62% vs 56%, p = 0.1) for recipients of PBSC relative to BM cells, but pre‐transplant disease status was the only significant variable by univariate analysis (Table I). By multivariate analysis, PBSC resulted a protective factor both for OS (HR: 0.29, p = 0.006), PFS (HR: 0.38, p = 0.001) and GRFS (HR: 0.44, p = 0.020). The other independent variables affecting the final outcome were pre‐transplant disease status and hematopoietic cell transplant comorbidity index (HCT‐CI) (Table I). Non‐relapse mortality was not affected by graft source both by univariate and multivariate analysis, while pre‐transplant disease status was the only variable affecting the chance of disease relapse.Summary/Conclusion:Overall these data suggest that PBSC is associated with better outcome, in terms of OS, PFS and GRFS, relative to BM cells as graft source for patients undergoing Haplo‐SCT with PT‐Cy. In addition, the risk of acute and chronic GVHD is not increased after PBSC relative to BM graft.image

Thiotepa-Based Intensified Reduced-Intensity Conditioning Adult Double-Unit Cord Blood Hematopoietic Stem Cell Transplantation Results in Decreased Relapse Rate and Improved Survival Compared with Transplantation Following Standard Reduced-Intensity Conditioning: A Retrospective Cohort Comparison

The “Minnesota” reduced-intensity conditioning (RIC) cord blood transplantation (CBT) regimen (standard RIC) of fludarabine (Flu) (200 mg/m2), cyclophosphamide (Cy) (50 mg/kg), and 200- or 300-cGy total body irradiation (TBI) is the most published RIC CBT regimen. Though well tolerated, high relapse rates remain a concern with this regimen. Intensification of conditioning may reduce relapse without increasing transplant-related mortality (TRM). We performed a retrospective cohort comparison of outcomes in adult patients who underwent first double-unit CBT with standard RIC as compared with the intensified regimen of Flu 150 mg/m2, Cy 50 mg/kg, thiotepa 10 mg/kg, and 400-cGy TBI (intensified RIC). Of the 99 patients studied, 47 received intensified RIC. Acute myelogenous leukemia was the major indication for transplant. The median age at transplant was 67 years (range, 24 to 74 years) and 54 years (range, 25 to 67 years) in standard RIC and intensified RIC, respectively. Median hematopoietic stem cell transplantation comorbidity index was 3 (range, 0 to 5) and 1 (range, 0 to 6) in the standard RIC and intensified RIC groups, respectively. Median follow-up among survivors was 22 months (range, 3.7 to 79 months) following standard RIC and 15 months (range, 2.8 to 36 months) following intensified RIC. The cumulative incidence (CI) of relapse was significantly lower following intensified RIC compared with standard RIC (P = .0013); this finding maintained significance in multivariate analysis (P = .045). TRM was comparable between the 2 groups (P = .99). Overall survival (OS) was significantly improved following intensified RIC as compared with standard RIC (P = .03). Median OS was 17 months following standard RIC versus not reached followed intensified RIC. The CI of grade II to IV acute graft-versus-host disease (GVHD) was significantly higher in the intensified RIC cohort than the standard RIC-cohort (P = .007), while CI of grade III to IV acute GVHD, any chronic GVHD, and moderate-to-severe chronic GVHD was comparable in each cohort (P = .20, P = .21, and P = .61, respectively). This retrospective analysis shows an improvement in OS and decreased relapse without increase in TRM in patients receiving intensified RIC as compared with standard RIC. Our data suggest that consideration of thiotepa-based intensified RIC may improve outcomes in fit, older patients undergoing double-unit CBT.

Age adjusted hematopoietic stem cell transplant comorbidity index predicts survival in a T-cell depleted cohort

ObjectivesAllogeneic hematopoietic stem cell transplant (HCT) continues to evolve with the treatment in higher risk patient population. This practice mandates stringent update and validation of risk stratification prior to undergoing such a complex and potentially fatal procedure. We examined the adoption of the new comorbidity index (HCT-CI/Age) proposed by the Seattle group after the addition of age variable and compared it to the pre-transplant assessment of mortality (PAM) that already incorporates age as part of its evaluation criteria. MethodsA retrospective analysis of adult patients who underwent HCT at our institution from January 2010 through August 2014 was performed. Kaplan-Meier’s curve, log-rank tests, Cox model and Pearson correlation was used in the analysis. ResultsOf the 114 patients that underwent allogeneic transplant in our institution, 75.4% were ≥40 years old. More than 58% had a DLCO ≤80%. Although scores were positively correlated (correlation coefficient 0.43, p < 0.001), HCT-CI/Age more accurately predicted 2-year overall survival (OS) and non-relapse mortality (NRM) in patients with lower (0–4) and higher (5–7) scores (52% and 36% versus 24% and 76%, p = 0.004, 0.003 respectively). PAM score did not reach statistical significance for difference in OS nor NRM between the low (<24) and high-risk (≥24) groups (p = 0.19 for both). ConclusionsDespite our small sample population, HCT-CI/Age was more discriminative to identify patients with poor outcome that might benefit from intensified management strategies or other therapeutic approaches rather than allogeneic HCT.

421 - Developing a Modified Hematopoietic Stem Cell Transplantation—Comorbidity Index for Adolescents and Young Adults

421 - Developing a Modified Hematopoietic Stem Cell Transplantation—Comorbidity Index for Adolescents and Young Adults

HCT.CI in Autologous Stem Cell Transplantation. Predicting Early and Late Transplant Related Mortality

Background. Hematopoietic Stem Cell Transplant Comorbidity Index (HCT.CI) score, described by Sorror, is a useful tool to assess the risk for Non Relapse Mortality (NRM) after Allogeneic HSCT. The impact of this score in Autologous HSCT is still to be confirmed.Aims. To determine the impact of HCT.Ci score in the morbidity and mortality after autologous HSCT, assessing the 100 day morbidity defined as orothraqueal intubation (OTI), dialysis or shock (defined as vasopressors need), 100 day mortality, early morbi-mortality (combined end-point by any of the previous end-point) and long term NRM.Materials and Methods. We retrospectively reviewed 1478 medical records of adult patients who received an autologous HSCT in our centre between October 2002 and April 2016. Median age was 49 years (range 16-74 years), 58% were male, prevalent diseases were Multiple Myeloma (48%), Non Hodgkin Lymphoma (27%) and Hodgkin Lymphoma (18%), 49% were in complete remission, 46% received one chemotherapy scheme before transplant, 41% two schemes and 12% three or more (heavily pre-treated). In respect to conditionings, melphalan was used in 48% of the cases, CBV in 25%, BEAM in 8% as well as BendaEAM. Seventy five percent received an infusion of stem cells CD34+≥3x10.6/kg. Regarding comorbidities, 58% had low risk (LR) HCT.CI (score 0), 32% intermediate risk (IR) (1-2) and 11% high risk (HR) (≥3). For univariate analysis we use Chi2 for dichotomic variables, Kaplan-Meier for Overall Survival (OS) and cumulative incidence for NRM; for multivariate analysis we used logistic regression for dichotomic and Cox regression for time dependant variables.Results. Median follow up was 1.9 years. Early mortality (day 100) was 2.8%, 5.6% required OTI, 4.8% required vassopresors and 2.2% dialysis, 1-3 years NRM and OS were 4.3-5.2% and 89-77% respectively. High risk HCT.Ci patients had a significant increase in 100 day mortality compared to IR and LR (7% vs.3% vs. 2% respectively, p=0.002), OTI (12% vs. 7% vs. 4%, p<0.001), dialysis (4.5% vs.2.6% vs. 1.5%, p=0.04), shock (10% vs.6.4% vs. 3%, p<0.001), early morbi-mortality (15% vs.9 % vs. 4.6%, p<0.001) and NRM (1-3 years 9.2-13% vs. 3.8-3.8% vs. 3.5-4.5%, p<0.001) (figure 1). After multivariate analysis these outcomes remain significant (showed as OR with 95% CI, IR and HR compared to LR): early mortality (1.8, 0.8-4.2 and 3.9, 1.6-9.7, p=0.003), OTI (2.1, 1.2-3.7, p<0.01 and 3.9, 2.0-7.5, p<0.001), dialysis (2.2, 0.8-5.5 and 4.1, 1.4-11.7, p<0.01), shock (2.7, 1.4-4.9, p=0.001 and 4.4, 2.1-8.9, p<0.001), early morbi-mortality (2.4, 1.4-4.0, p=0.001 and 4.2, 2.3-7.6, p<0.001) and NRM (1.3, 0.7-2.4 and 3.0, 1.5-5.7, p=0.001) (table 1). No significant impact was observed in OS. Other than comorbidities, significant impact was observed in early mortality (pre-transplant status, heavily pre-treated patients and BendaEAM conditioning), OTI (NHL, heavily pre-treated patients, BendaEAM conditioning), dialysis (pre-transplant status and BendaEAM conditioning), shock (NHL, heavily pre-treated patients and BendaEAM conditioning), morbi-mortality (NHL and BendaEAM conditioning) and NRM (male patients, NHL, pre-transplant status, heavily pre-treated patients and BendaEAM conditioning).Conclusions. We observed that HCT.CI had a significant impact on Autologous HSCT treatment related mortality basically due to early toxicity express as 100 day mortality and the three main morbidity outcomes as well as the combined end point. This observation should be confirmed in larger series. [Display omitted] [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Implementation of a Physician-Prescribed Exercise Program As Standard of Care in Allogeneic Stem Cell Transplant (SCT) Patients (pts) in British Columbia: A Pilot Study

Background: There is compelling evidence that physical activity positively influences quality of life (QoL), and health-related outcomes including improved muscle mass and physical functioning in cancer pts. SCT pts however have unique barriers to exercise including isolation, restriction of activities, and treatment toxicity. In the early post SCT period, pts describe worsening fatigue, physical capacity and QoL. We sought to determine whether a partially supervised exercise intervention early post SCT would address these issues. Our primary objective was to determine the feasibility of delivering such an intervention at our institution. Secondary objectives were to assess changes as a result of the intervention in QoL, muscle mass and physical functioning.Methods: From Aug 2015-Jun 2016, we conducted a prospective single-arm study to evaluate feasibility of a 12 week partially supervised exercise program (1 supervised, 2 unsupervised sessions/week) for alloSCT pts with hematologic malignancies. The program consisted of 3 progressive endurance (stationary bike, walking) and 2 resistance training sessions/week, from hospital discharge (D/C) to Day (D) 100. Feasibility was defined as ability to recruit >65% of eligible pts, ≥70% retention and ≥70% adherence. Secondary outcomes were measured pre SCT (T0), at D/C (T1) and D100 (T2) and included QoL, muscle strength, mobility, aerobic fitness and body composition. Changes from T0 to T1 and T1 to T2 were compared using a paired sample t-test.Results: Of 43 consecutive alloSCT pts assessed for eligibility, 30 (70%) entered the study: 17 male (57%), median age 48 yrs (range 19-66 yrs). Transplants characteristics were: related 6; unrelated 24; myeloablative 23; reduced intensity 7. At baseline, SCT comorbidity index was 0 in 43%, 1-2 37%, ≥ 3 20%. Pts self-reported exercising enough to break a sweat (Godin et al) never 60%, sometimes 33%, often 7%. Median hospitalization was 29d (range 15-141); 9 pts developed grade II-IV acute graft-versus-host disease (skin 7, gut 5, liver 1).Overall retention to D100 was 80% (Figure 1). Two pts had complications during hospitalization and did not enter the program. Of the 24 pts who entered the program, adherence was 72% for supervised and 89% for unsupervised sessions. Logistics with scheduling around multiple medical appointments in the early post SCT period were the most common reasons for non-adherence. Other reasons included nausea, fatigue and weakness. One pt developed exercise-induced atrial fibrillation in week 3 requiring cessation of exercise.When comparing secondary outcomes from T0 to T1 (Table 1), pts had significantly decreased muscle strength (grip strength, 30-second chair stand), mobility (timed up-and-go [TUG]) and aerobic capacity (6-min walk test [6MWT]). At T2 after completion of the program, these measures all increased significantly when compared to T1. Global QoL scores on the EORTC measure decreased from T0 to T1 (P=.011) and were significantly improved by T2 (P<.001). Similar trends were seen across functional and symptom measure scales. Body composition comparisons between T0 and T2 demonstrated a trend towards increased appendicular lean mass (P<.059).Conclusion: Results of this pilot study demonstrate feasibility of a partially supervised exercise program post-alloSCT deemed by achieving the target recruitment rate, ≥70% adherence and ≥70% retention. Logistics were the most common reason for non-adherence, highlighting need for a multidisciplinary team with knowledge of the post SCT setting. Prior observational studies have shown significant declines in physical functioning and QoL within the first 100 days of SCT. In contrast we demonstrate significant improvements in these measures. Furthermore, we demonstrate a trend towards increased lean muscle mass, which is a novel secondary outcome that warrants further evaluation in this setting. Our findings support the need for this clinical intervention and will be evaluated in a larger randomized trial. [Display omitted] [Display omitted] DisclosuresGerrie:Roche Canada: Research Funding. Plantinga:BCCA: Employment. Broady:Lotte & John Hecht Memorial Foundation: Research Funding.