Low-dose Alemtuzumab Research Articles

410.8: Our unique experience with low dose Alemtuzumab as induction agent in renal transplantation.

410.8: Our unique experience with low dose Alemtuzumab as induction agent in renal transplantation.

Standardized, risk-adapted induction therapy in kidney transplantation.

The choice of induction therapy in kidney transplantation is often non-standardized and centre-specific. Clinicians can choose between depleting and non-depleting antibodies, which differ in their immunosuppressive capacity and the concomitant risk of infection. We herein present a standardized risk-stratified algorithm for induction therapy that might help to balance the risk of rejection and/or serious infection. Prior to kidney transplantation, patients were stratified into low-risk, intermediate-risk or high-risk according to our protocol based on immunologic risk factors. Depending on their individual immunologic risk, patients received basiliximab (low risk), antithymocyte globulin (intermediate risk) or low-dose alemtuzumab (high risk) for induction therapy. We analysed the results after 3years of implementation of our risk-stratified induction therapy protocol at our kidney transplant centre. Between 01/2017 and 05/2020, 126 patients were stratified in accordance with our protocol (low risk/intermediate risk/high risk: 69 vs. 42 vs. 15 patients). The median follow-up time was 1.9 [1.0-2.5] years. No significant difference was observed in rejection rate and allograft survival (low risk/intermediate risk/high risk: 90.07% vs. 80.81% vs. 100% after 3 years (p > 0.05)) among the groups. The median eGFR at follow-up was (low risk/intermediate risk/high risk) 47 [33-58] vs 58 [46-76] vs 44 [22-55] ml/min/1.73 m2. Although the rate of viral and bacterial infections did not differ significantly, we observed a higher rate of opportunistic fungal infections with alemtuzumab induction. Our strategy offers facilitated and individualized choice of induction therapy in kidney transplantation. We propose further evaluation of our algorithm in prospective trials.

Intense Immunosuppressive Therapy (anti-thymocyte globulin, alemtuzumab) As Salvage Therapy in Refractory T-Cell Large Granular Lymphocytic Leukemia and Pure Red Cell Aplasia

Background T-cell directed immunosuppression (IS: methotrexate, cyclosporine, and cyclophosphamide) is the main treatment modality applied for the therapy of immune single-lineage cytopenias including idiopathic neutropenia and pure red cell aplasia (PRCA). These two conditions are likely T-cell mediated and are often associated with T-cell large granular lymphocytic leukemia (T-LGL). The latter is thought to result from an originally polyclonal process evolving to a clonal proliferation of cytotoxic T-lymphocytes. Generally, response to 1st line therapies is about 30%, whereas rates as high as 80-90% can be achieved with 2nd, and 3rd lines. However, a significant fraction of patients remains refractory to multiple therapies and constitutes a management challenge. These patients remain transfusion dependent and/or have severely depressed neutrophil counts refractory to granulocyte-colony stimulating factor (G-CSF). In this scenario, intense IS with anti-thymocyte globulin (ATG) and alemtuzumab is often considered a salvage option, but no systematic experience exists and only a few controlled clinical trials have been conducted. Particularly, we previously reported an overall response rate (ORR) of 63% (n=23) with low dose alemtuzumab (10 mg sc q week x10) and 2/2 with ATG (40 mg/kg/d x 4 days) in patients with PRCA and/or LGL. Previous experience showed an ORR of 74% in a phase II study of 19 T-LGL patients treated with alemtuzumab, whereas a literature meta-analysis showed an ORR of 33% in 24 patients with PRCA treated with ATG. To better rationalize salvage therapy for refractory immune cytopenias, we explored the effectiveness of these agents at our tertiary referral center. Design and Methods We retrospectively examined treatment outcomes in 296 patients with LGL (113 had neutropenia and 73 anemia), and 78 patients with PRCA (+/- LGL). The study cohort had severe refractory cytopenia despite multiple treatment regimens and received salvage therapy with ATG and/or alemtuzumab. Complete response (CR) was defined as hemoglobin >10 g/dL, and absolute neutrophil count >1.0x109/L. Partial response (PR) was defined not meeting CR criteria. Response to therapy was evaluated while on therapy (alemtuzumab) and 4 months post-therapy (ATG). Overall response rate (ORR) was calculated as the percentage of patients with both CR and PR over the total number of patients who received the drug. The response rate was not available for 4 and 3 cases in the ATG and alemtuzumab cohorts respectively. Results A total of 62 patients who received salvage therapy with ATG (N=23) and alemtuzumab (N=39) for refractory cytopenia associated with LGL (N=38) and without LGL (N=24) were identified. Overall, the median age at disease onset was 58 years (IQR 45-69) with a 1.2 male to female ratio. On average, patients received 4 treatment modalities prior to ATG/alemtuzumab to which they did not respond or became refractory. CR rate (CRR) for patients treated with ATG was 42% (8/19) and ORR 89% (17/19). The CRR and ORR was 22% (8/36) and 81% (29/36), respectively in patients treated with alemtuzumab. No significant difference was observed in terms of ORR in patients treated with alemtuzumab compared to ATG (P = 0.45). In T-LGL cases, the presence of a STAT3 mutation did not impact an ORR to either alemtuzumab (31 vs 45% in STAT3 wild type) or ATG-treated cases (54 vs 38%). There was no significant difference in the LGL and PRCA (+/- LGL) cohorts treated with alemtuzumab (P = 0.89) and ATG (P = 0.13). Overall, no treatment-related death was registered, and toxicities were manageable. Alemtuzumab was held if absolute lymphocyte count was <200/µL. Of note, only one patient had CMV re-activation in our cohort. Conclusion Our data shows that alemtuzumab and ATG represent salvage IS regimens highly effective for the treatment of T-LGL and PRCA refractory to multiple lines of therapy with ORR higher if compared to historical data. This therapy resulted in a durable response in both T-LGL and PRCA (+/- LGL) with a good safety profile. The use of low dose alemtuzumab greatly decreases the complication rate and tolerability.

Patients with Chronic Lymphocytic Leukemia Belonging to the B-Cell Receptor Stereotypy Subset #2 Have Long Progression Free Survival after Chemo- or Chemoimmunotherapy in the HOVON68 Trial

Abstract Introduction: About one third of all patients with Chronic Lymphocytic Leukemia (CLL) have quasi-identical, so-called stereotyped B-cell receptors (BCR) that can be divided into subsets (Agathangelidis et al. Blood 2012). At present, 19 major subsets have been described that account for approximately 12% of all patients with CLL. Of these, subsets #1 and #2 are associated with a poor prognosis (Baliakas et al. Lancet Hematology 2014). The HOVON68 trial compared fludarabine and cyclophosphamide (FC) chemotherapy to chemo-immunotherapy with low-dose alemtuzumab (FCA) as a first line treatment in selected high risk patients defined as either harboring 17p deletion, 11q deletion, trisomy 12, having unmutated mmunoglobulin heavy variable genes (IGHV) and/or VH3-21. The study showed a benefit of adding low-dose alemtuzumab to FC (Geisler et al. Blood 2014). Here, we studied the impact of BCR stereotypy subsets on the primary outcome progression free survival (PFS) and overall survival (OS). Methods: Sequences from IGHV mutational analyses were collected from participating centers in Sweden, Norway, Finland, Denmark, and the Netherlands. Subsets were assigned based on the ARResT/AssignSubsets software (Bystry et al. Bioinformatics 2015). Analysis for recurrent mutations were performed by next generation sequencing by a 454 based platform (Roche Diagnostics Corporation, Indianapolis, USA). All other clinical data were extracted from the HOVON database as of November 2016. Kaplan-Meier curves, log-rank tests, and Cox regression models were used for survival analysis. Fisher's exact test was used for contingency table analysis. P-values Results: A total of 187 sequences were available. Of these, 176 were suitable for analysis. We found a total of 37 patients (21%) that could be assigned to one of the 19 major subsets: Subset #2 was the most frequent (n=12, 6.8%), thereafter subset #8 (n=7, 4.0%), subset #6 (n=6, 3.4%), and subset #1 (n=5, 2.8%). The median follow-up time for patients still alive was 78.6 months. By November 2016, 148 patients (84%) had had an event (no response to treatment, progression, or death) and 77 patients (44%) had died. Compared to patients belonging to other major subsets, patients with subset #2 did not differ significantly as to: age group above 65 years, gender, treatment arm, cytogenetic aberrations by FISH, WHO performance status, beta2microglobulin level>3.5 mg/L, or in complete response rates, However, patients with subset #2 had more advanced disease (Binet stage C 83% vs. 52%, p=0.04) and as expected less often unmutated IGHV genes (67% vs. 100%, p=0.01). Nineteen of 37 patients (51%) was analyzed for recurrent mutations: Only SF3B1 mutations was found in patients with subset #2, and the frequency was slightly higher compared to other major subsets (57% vs. 17%, p=0.13), in whom also KRAS2 (17%) and BRAF15 (8%) mutations was found. Unexpectedly, patients with subset #2 had a longer PFS compared to patients with other major subsets (median PFS #2: 51.2 months vs. other major #: 31.1 months, p=0.002, Figure), or compared to patients with usage of the same IGHV gene (e.g. median PFS for 7 patients with VH3-21/non #2: 15.4 months, p Discussion and conclusions: As expected, stereotypy was found more frequently in the HOVON68 trial that selected for high risk patients as compared to patients from large multi-institutional studies (Stamatopoulos at al. Leukemia 2017). Surprisingly, patients belonging to subset #2 had a better PFS after chemo-(immuno) therapy compared to other major subsets, albeit the numbers are small. Our data suggest that, chemo-(immuno) therapy may still have a place for patients otherwise assessed as ‘high risk’ such as patients with B-cell receptor stereotypy subset #2. Thus, selection of patients for trials as well as the exact treatment regimen may have major impact on the significance of biomarkers. Download : Download high-res image (115KB) Download : Download full-size image Figure . Disclosures Vojdeman: Roche: Other: Travel support in 2015; Gilead: Other: Travel support. Kimby: Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Abbvie: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria; Celgene: Research Funding; Pfizer: Research Funding. Van Oers: Roche: Consultancy; ISA therapeutics: Consultancy; Novartis: Consultancy; Immunicum: Consultancy. Kater: Celgene: Consultancy, Research Funding; Johnson & Johnson: Research Funding; Abbvie: Research Funding. Niemann: Roche: Consultancy, Other: Travel grant; Janssen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant; Novo Nordisk Foundation: Research Funding; The Danish Cancer Society: Research Funding; Novartis: Other: Travel grant; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Other: Travel grant, Research Funding.

Repetitively Administered Low-Dose Donor Lymphocyte Infusion for Prevention of Relapse after Allogeneic Stem Cell Transplantation in Patients with High-Risk Acute Leukemia.

Simple SummaryPatients with high-risk acute leukemia (AL) have a high risk of relapse after allogeneic stem cell transplantation (allo-SCT). Prophylactic donor lymphocyte infusion (pro-DLI) has shown significant efficacy in reducing relapse rate but its widespread application has been limited due to concerns of graft versus host disease (GVHD) development. In the present study, we tested the safety and efficacy of a novel method of pro-DLI based on repetitive administration of low lymphocyte doses. Low-dose pro-DLI was administered every two months for at least 3-years. Forty-four high-risk AL patients with a median age of 53-years who underwent allo-SCT from a matched-sibling (38pts) or a matched-unrelated donor (6pts) received pro-DLI. Acute and chronic-GVHD developed in 14% and 12% of patients. With a median follow-up of 44-months, the cumulative incidence of relapse and non-relapse mortality was 12% and 13%, while the overall survival was 78%. Prolonged up to 3-years low-dose pro-DLI administered every two months is safe and effective in reducing relapse rate in patients with high-risk AL. The low-dose repetitive administration DLI strategy reduced the risk of DLI-mediated GVHD, while the prolonged repeated administration helped in preventing relapse, possibly by inducing a sustained and prolonged immunological pressure on residual leukemic cells. Background: Patients with high-risk acute leukemia have a high risk of relapse after allogeneic stem cell transplantation (allo-SCT). In an effort to reduce the relapse rate, various therapeutic methods have been implemented into clinical practice. Among them, prophylactic donor lymphocyte infusion (pro-DLI) has shown significant efficacy. However, the widespread application of pro-DLI has been restricted mostly due to concerns regarding the development of graft versus host disease (GVHD). In the present study, we tested the safety and efficacy of a novel method of prophylactic-DLI based by repetitive administration of low lymphocyte doses. Methods: DLI was administered to patients with high-risk acute leukemia at a dose of 2 × 106/kg CD3-positive cells. DLI at the same dose was repeated every two months for at least 36 months post-allo-SCT, or until relapse or any clinical or laboratory feature suggested GVHD, whichever occurred first. Forty-four patients with a median age of 53 years (range 20–67) who underwent allo-SCT between 2011 and 2020 were included in our study. Thirty-three patients with high-risk acute myeloid leukemia (AML) and 11 with high-risk acute lymphoblastic leukemia (ALL) after allo-SCT from a matched sibling (MSD, no = 38 pts) or a matched-unrelated donor (MUD, no = 6 pts) received pro-DLI. Twenty-three patients were in CR1, all with unfavorable genetic features; 12 patients were in CR2 or beyond; and 9 patients had refractory disease at the time of transplant. Ten out of 23 patients in CR1 had detectable minimal residual disease (MRD) at the time of allo-SCT. Disease risk index (DRI) was high and intermediate in 21 and 23 patients, respectively. Conditioning was myeloablative (MAC) in 36 and reduced intensity (RIC) in 8 patients, while GVHD prophylaxis consisted of cyclosporine-A in combination with low-dose alemtuzumab in 39 patients or with low-dose MTX in 5 patients, respectively. Results: Thirty-five patients completed the scheduled treatment and received a median of 8 DLI doses (range 1–35). Fifteen out of 35 patients received all planned doses, while DLI was discontinued in 20 patients. Reasons for discontinuation included GVHD development in nine, donor unavailability in seven, disease relapse in three, and secondary malignancy in one patient, respectively. Nine patients were still on treatment with DLI, and they received a median of four (range 2–12) doses. Fourteen percent of patients developed transient grade-II acute GVHD while 12% developed chronic GVHD post-DLI administration. Acute GVHD was managed successfully with short course steroids, and four out of five patients with cGVHD were disease-free and off immunosuppression. With a median follow-up of 44 months (range 8–120), relapse-free (RFS) and overall survival (OS) were 74%, (95% CI, 54–87%) and 78%, (95% CI, 58–89%) respectively, while the cumulative incidence of non-relapse mortality (NRM) was 13% (95% CI, 4–28%). The cumulative incidence of relapse in patients with intermediate and high DRI is 7% and 15%, respectively. Conclusion: Prolonged—up to three years—low-dose pro-DLI administered every two months is safe and effective in reducing relapse rate in patients with high-risk acute leukemia. The low-dose repetitive administration DLI strategy reduced the risk of DLI-mediated GVHD, while the prolonged repeated administration helped in preventing relapse, possibly by inducing a sustained and prolonged immunological pressure on residual leukemic cells. This novel strategy deserves testing in larger cohort of patients with high-risk acute leukemia.

Low-dose alemtuzumab induction in a tailored immunosuppression protocol for sensitized kidney transplant recipients

BackgroundInduction therapy is crucial in kidney transplantation and constitutes an important cornerstone for long-term allograft survival. Alemtuzumab is a depleting CD52-specific antibody with T- and B-cell activity, leading to prolonged lymphocyte depletion for up to 12 months, with profound immunosuppression and an associated risk of serious infections. Current concepts aim to optimize dosing strategies to reduce side effects. Here we present data from an ongoing centre protocol consisting of low-dose alemtuzumab induction and tailored immunosuppression in sensitized patients undergoing kidney transplantation.Methods10-year results of the protocol were analysed. Low-dose alemtuzumab induction consisted of a single dose of 20 mg intraoperatively, followed by tacrolimus and corticosteroids for initial immunosuppression, with mycophenolate mofetil suspended until a total lymphocyte count (TLC) >5% or 200/μl was reached.ResultsBetween 01/2007 and 04/2017, 46 patients were treated in accordance with the protocol in 48 kidney transplantations. Median PRAmax was 43 [22-76; IQR] %; all patients had negative CDC-crossmatch prior to transplantation. Low-dose alemtuzumab was well tolerated. Median time to TLC recovery was 77 [62-127; IQR] d. Within a median follow-up of 3.3 [1.5-5.6; IQR] years, 12 (25%) patients developed BPAR, 10 of which were antibody-mediated (3 acute, 7 chronic ABMR). Death-censored 5-year allograft survival was 79.2%, with an excellent allograft function at the end of follow-up. There was no increased rate of infections, in particular viral infections.ConclusionsOur protocol, comprising low-dose alemtuzumab induction, initial suspension of mycophenolate mofetil and triple maintenance immunosuppression, provides excellent patient and allograft outcome in sensitized renal allograft recipients.

No indication of increased infection rates using low-dose alemtuzumab instead of anti-thymocyte globulin as graft-versus-host disease prophylaxis before allogeneic stem cell transplantation.

Alemtuzumab as part of the conditioning protocol is effective in reducing graft-versus-host disease (GvHD), but may be associated with increased infection rates, especially when using high doses (ie, 100mg). We performed a retrospective, single-center, case-control study analyzing the rates of neutropenic fever, cytomegalovirus (CMV) reactivation, Epstein-Barr virus (EBV) reactivation, clinical manifest toxoplasmosis, and clinical manifest human herpesvirus-6 (HHV6) infection using low-dose alemtuzumab in comparison with anti-thymocyte globulin (ATG) as GvHD prophylaxis before allogeneic stem cell transplantation. Forty-four patients transplanted from unrelated donors between 2001 and 2012 were matched by age, diagnosis, and conditioning regimen and treated either with alemtuzumab 10mg at day -2 (respectively, 20mg in case of mismatch transplantation) or ATG. ATG Fresenius (10mg/kg for 3days) or Thymoglobulin (2mg/kg for 3days) were used. Rates of CMV reactivation, EBV reactivation, and clinical manifest HHV6 infection or toxoplasmosis did not differ significantly between both groups until 2years after transplantation. No case of post-transplant lymphoproliferative disorder was observed. Also, rates of neutropenic fever during inpatient treatment after transplantation did not differ significantly in both groups. We saw no indication of increased infections rates when using low-dose alemtuzumab as GvHD prophylaxis before allogeneic stem cell transplantation in this retrospective analysis.

Are the Polyomaviruses BK and JC Associated with Opportunistic Infections, Graft-versus-Host Disease, or Worse Outcomes in Adult Patients Receiving Their First Allogeneic Stem Cell Transplantation with Low-Dose Alemtuzumab?

Background: The association of polyomaviruses BK and JC with other opportunistic infections and graft-versus-host disease (GvHD) in allogeneic stem cell transplantation is controversially discussed. Methods: We conducted a retrospective study of 64 adult patients who received their first allogeneic stem cell transplantation between March 2010 and December 2014; the follow-up time was 2 years. Results: Acute leukemia was the most frequent underlying disease (45.3%), and conditioning included myeloablative (67.2%) and nonmyeloablative protocols (32.8%). All patients received 10 mg of alemtuzumab on day -2 (20 mg in case of mismatch) as GvHD prophylaxis. Twenty-seven patients (41.5%) developed cytomegalovirus (CMV) reactivation. BKPyV-associated hemorrhagic cystitis was diagnosed in 10 patients (15.6%). Other opportunistic infections caused by viruses or protozoa occurred rarely (<10%). There was no association of BKPyV or JCPyV with CMV reactivation, Epstein-Barr virus reactivation, human herpes virus 6, or parvovirus B19 infection requiring treatment. There was a significant correlation of BKPyV-associated hemorrhagic cystitis with toxoplasmosis (p = 0.013). Additionally, there was a significant link of simultaneous BKPyV and JCPyV viruria with toxoplasmosis (p = 0.047). BKPyV and JCPyV were not associated with GvHD, relapse, or death. Conclusion: We found no association of BKPyV or JCPyV with viral infections or GvHD. Only the correlation of both polyomaviruses with toxoplasmosis was significant. This is a novel and interesting finding.

Infliximab and Low Dose Alemtuzumab in Patients with Steroid-Refractory Acute Graft-Versus-Host Disease

Introduction:Steroid-refractory grade IV acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT) carries a mortality rate of approximately 80%. Trials of novel therapies including antibodies directed against the T-cell immune response have generally failed to improve outcomes although may lead to responses. Infliximab, a chimeric monoclonal antibody to TNF alpha, and alemtuzumab another monoclonal antibody targeting CD52, an antigen expressed on T and B lymphocytes and other antigen presenting cells (APCs) both have produced response rates in the 50-75% range. However, few are long-term survivors as the majority die of opportunistic infections (OI). While steroids are ineffective in many series, they are continued when novel agents are employed. We have approached steroid-refractory aGVHD with a combination of rapid steroid discontinuation, standard doses of infliximab and short course low dose alemtuzumab with the hope for aGVHD control without early deaths from OIs.Methods:We identified all patients who were treated for steroid-refractory aGVHD between January 1, 2014 and March 1, 2016 at Loyola University Medical Center. The diagnosis of aGVHD was made by clinical criteria per the National Institutes of Health guidelines. The diagnosis was confirmed by endoscopic evaluation and biopsy of the affected organ. All patients received methylprednisolone 2 mg/kg/day IV given in twice daily dosing for at least 7 days prior to being considered steroid-refractory. Patients received infliximab 10 mg/kg IV infusion weekly x 2 then every other week until remission and alemtuzumab 3 mg IV test dose on day 1, followed by 10 mg IV daily for 4 days. At the same time steroids were reduced by 50% and further reductions of 50% were made every 4 days. Responses were assessed by daily grading of aGVHD per Glucksberg criteria after dosing of infliximab and alemtuzumab. A complete response (CR) was defined as full resolution of abdominal pain, diarrhea, rectal bleeding, liver function test abnormalities, or skin involvement. A partial response (PR) was defined as a 50% improvement in diarrhea, liver function abnormalities, or skin involvement with a decrease in 1 or more grade levels of aGVHD per Glucksberg criteria.Results:To date 6 patients have been treated for steroid-refractory aGVHD after matched related donor (MRD) or matched unrelated donor (MUD) HSCT. Patient characteristics are shown in Table 1. There were 5 patients who underwent a MRD or MUD HSCT for myelodysplastic syndrome (MDS), and 1 patient who underwent a MUD HSCT for B-cell acute lymphoblastic leukemia (B-ALL). Median age at treatment was 64 years. All patients had Glucksberg grade 4 aGVHD (Table 1). The overall response rate (ORR) was 83% with 4 patients achieving a PR, 1 patient achieving CR, and 1 patient with no response to treatment. Day 100 survival after dosing of alemtuzumab was 50% with deaths due to aGVHD in 2 patients and death due to septic shock in 1 patient. CMV reactivation occurred in 4 patients and EBV reactivation occurred in 1 patient.Conclusion:In our single institution analysis, the combination of infliximab and alemtuzumab with rapid steroid withdrawal achieved a high ORR of 83% in treatment of steroid-refractory aGVHD after MRD or MUD HSCT with an encouraging 50% survival at day 100. This approach will be continued to further define its efficacy and safety for the treatment of steroid-refractory aGVHD. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Subcutaneous Low Dose Alemtuzumab: Role As a Salvage Therapy in Immune -Mediated Marrow Failure Conditions

▪Aplastic anemia (AA), pure red cell aplasia (PRCA), pure white cell aplasia (PWCA), idiopathic neutropenia (IN) and T cell large granular lymphocytic leukemia (LGL) are bone marrow failure (BMF) conditions unified by immune-mediated pathogenesis leading to cytopenias. Intravenous alemtuzumab, a CD52 monoclonal antibody approved for the treatment of chronic lymphocytic leukemia (CLL) and used for relapsed AA, has a response rate in AA of 37-58%. However, dosing and route was likely based on those used in CLL regimens and resulted in significant immunosuppressive complications.Here we summarize our experience with sc alemtuzumab given at the maximum dose of total 100 mg as etiologic treatment (either salvage therapy or preferred therapy) to patients with various BMF. We investigated the therapies administered to patients seen at the Cleveland Clinic or at the University of Naples (NCT00895739) between years 2002-2015.Of 484 patients with BMF conditions (Cleveland: AA: 204, LGL: 174, PRCA: 56; Naples: AA: 24, LGL: 2, PRCA: 14), 65 patients with AA (N=22), PRCA (N=22), LGL (N=18) and 3 cases of IN/PWCA were treated sc alemtuzumab, given according 2 distinct schedules: i. initial dose of 3 mg sc followed by 10 mg once or twice weekly for at least 8 consecutive weeks; ii. 4-5 day dose escalation (3-10-30-30-30 mg) regimen. In both schedules, some patients received a much longer course with maintenance treatment or occasional boosts to prevent or treat relapse. Patients received bactrim and acyclovir prophylaxis, IVIG for hypoglobulinemia and underwent CMV monitoring. The median age of patients was 57.5 years (range: 31-84 years). Alemtuzumab was used as salvage therapy in Cleveland (except for 3 AA cases with contraindication to anti-thymocyte globulin or cyclosporine), whereas in Naples untreated patients were allowed per protocol. As a result, patients had a median of 2 lines of therapy (range: 0-6), had either untreated (35%), relapsed (22%) or refractory (43%) BMF condition. Among the 22 AA patients 12 were untreated, or had relapsed (N=4), or refractory disease (N=6), with concomitant PNH clone in 8/22 patients. LGL patients (N=18) treated with alemtuzumab were younger, had a median of 2 prior therapies, 50% were STAT3 mutants, with comparable degree of cytopenias but excess splenomegaly (60% vs. 38%, p=.012) at presentation, compared to the remainder LGL cohort. Amongst these patients, 18% had relapsed LGL while the rest had refractory disease. PRCA cases treated were either idiopathic (N=18, of whom 3 associated with thymoma) or LGL-associated (N=4); this group was very heterogeneous, including 9 untreated patients (in Naples) and a subgroup of heavily pretreated patients (5 with refractory disease) with a median of 5 prior therapies, with mean hemoglobin of 7.5 g/dL. Among the group of PWCA/IN, one case of PWCA was LGL-associated.The treatment was well tolerated in 92% of the patients, except in four patients who did not complete treatment course due to adverse events. The main adverse events include infectious complications with 7/65 developing CMV reactivation, 4/65 HSV reactivation, and more rarely other viral reactivation (VZV and HBV, 1/65 each). Two fatal infections were recorded: 1 fungemia (heavily pretreated with other therapies) and 1 JCV-related PML (in a patients also receiving chemotherapy for refractory thymoma).The overall response rate was 55%; by disease subtype 54% of AA, 44% of LGL, 59% of PRCA and all three cases of PWCA/IN responded. The median time to response in AA was 12 weeks (range: 6-24 weeks), and responses lasted a median of 6 months (range: 2-72 months). In AA, we observed responses in 72% of the cases treated with almetuzumab upfront and 45% of the relapsed/refractory disease. Similarly in PRCA cases, 77% of the alemtuzumab upfront and 46% of the relapsed/refractory disease responded. With a median follow up >4 years, no late treatment-related complication emerged; treatment failures were mostly due to relapses (sometimes refractory to further immunosuppressive treatment), with clonal evolution around 15% (mostly in non-responders).In summary, low-dose sc alemtuzumab is a reasonable alternative option for patients with BMF conditions, especially in relapsed/refractory cases; patients need to be monitored with a heightened vigilance for infectious complications, as well as for possible recurrence of their underlying disease. DisclosuresRisitano:Alexion Pharmaceuticals: Other: lecture fees, Research Funding; Alnylam: Research Funding; Rapharma: Research Funding; Novartis: Research Funding.

Reduced Intensity Conditioning with Fludarabine, BCNU and Melphalan (FBM) for Allogeneic Hematopoietic Cell Transplantation in Elderly AML Patients: Factors Predicting Outcome

Introduction: With the introduction of reduced-intensity conditioning (RIC), the age limit for allogeneic transplantation of AML patients has risen to 65 and above. In order to balance a low transplant-related mortality (TRM) with high anti-leukemic efficacy, Marks et al.1 introduced FBM conditioning consisting of 150mg/m2 Fludarabine, 300mg/m2 BCNU and 110mg/m2 Melphalan as RIC for elderly patients with encouraging results. However, no detailed analysis of factors predicting outcome in this subpopulation has been presented so far.Methods: In this two-center retrospective study, 51 patients (pts) with a median age of 64 y (range, 44-75y) diagnosed with AML were uniformly treated according to the FBM protocol. GvHD prophylaxis consisted of Ciclosporin A (CYA) and mycophenolate mofetil (MMF) in all patients. MMF was tapered after d50 and CYA after d90 in the absence of GvHD. Pts with matched unrelated donors (MUD) (n=33) or mismatched unrelated donors (MMUD) (n=9) received additional ATG or low dose alemtuzumab as GvHD and rejection prophylaxis. 9 pts with matched related donor (MRD) only received CYA and MMF as GvHD prophylaxis. Stem cell source was peripheral blood in 90% (n=46) and marrow in 10% (n=5) of the patients. The median number of transfused CD34+ cell was 7.1 million per kg body weight. The median follow-up at the time of analysis was 27 months. At the time of transplant 38 pts were in complete remission; the rest of the pts had active disease (partial remission or refractory disease). Molecular (NPM1, FLT3-ITD and CEBPA a) and cytogenetic characteristics (evaluable in 50 patients) were available for all patients.Results: Acute regimen-related toxicity was low, with a d30 mortality of 0 % in both centers. After 2 years, treatment failure was mainly due to relapse (CIR) with 36% (SE: 8%) in comparison to TRM (20%, SE: 7%). The resulting progression-free survival (PFS) and overall survival (OS) at 2 years was 50 % (SE: 5%) and 61% (SE: 7%), respectively.The median EBMT score was 4 (range 2-6). The EBMT score had no impact on different outcome variables (CIR (p=0.465), PFS (p=0.352) and OS (p=0.171)). Based on cytogenetic and molecular data patients were categorized according to the European LeukemiaNet (ELN) classification. 10% (n=5) of the patients belonged to the ELN favorable, 39% (n=20) to the ELN intermediate I, 29% (n=15) to the ELN intermediate II and 22% (n=11) to the ELN adverse risk group. Neither the ELN score itself nor stratification according to FLT3 -ITD or NPM1 mutation status or cytogenetic risk group impacted on outcome in our cohort. A trend for an improved OS in patients with NPM1 mutation (not stratified for FLT3-ITD or FLT3-TKD) was detected (p=0.255). By analyzing further risk factors such as remission status, donor type, age, CMV status, CD34+ cell number and acute or chronic GvHD we found the disease status at the time of transplant being the dominant predictor for OS. After 2 years patients transplanted not in remission had only an OS of 20% (SE: 8%) as compared to 75% (SE: 12%) in patients transplanted in CR (p<0.001) (Figure 1).Conclusion: In this cohort of elderly patients with AML receiving allogeneic transplantation after FBM conditioning, disease status at the time of transplant was the dominant prognostic factor for outcome. At the present follow-up neither molecular status nor cytogenetics impacted OS, PFS or CIR, significantly. We conclude that alternative strategies have to be applied using FBM conditioning in refractory patients, i.e. the early tapering of immunosuppression and the use of donor lymphocytes or cytoreduction immediately before the start of conditioning. An additional focus should be on novel compounds, which might help to increase CR rates at time of transplant.

Low-dose alemtuzumab in refractory/relapsed chronic lymphocytic leukemia: Genetic profile and long-term outcome from a single center experience.

Relapsed/refractory chronic lymphocytic leukemia (CLL) represents a clinical challenge, in particular when high risk gene mutations occur. In this setting, alemtuzumab was recognized to be effective. This retrospective study evaluates long-term efficacy and tolerability of low-dose alemtuzumab in relapsed/refractory CLL and correlates clinical outcome with biological feature. Sixty-two consecutive patients (median age 68 years) were evaluated; alemtuzumab was administered 30 mg weekly for up to 18 weeks. Among the patients included in the analysis, 37% were fludarabine-refractory, 33.3% carried a TP53 disruption, 14.8% a NOTCH1 mutation and 9% a SF3B1 mutation. Overall response rate (ORR) was 61.3% (complete remission 25.8%). After a median follow-up of 43 months, overall survival (OS) and progression free survival (PFS) were 43.1 and 15 months, respectively; while ORR was 77.8% for patients carrying TP53 disruptions (OS 33.8 months) and 43.5% for fludarabine-refractory patients (OS 30 months). Noteworthy, long-term survivors (OS ≥ 36 months) were 54.8%. None of the biological poor risk factors negatively impacted on ORR, PFS and OS. Grade ≥3 cytopenia occurred in 24.2% patients, 6.5% experienced a grade ≥3 non-CMV infection and no grade ≥3 CMV-event occurred. In conclusion, low dose-alemtuzumab is safe and effective in relapsed/refractory CLL, also in a long-term follow-up and high-risk genetic subgroups.

Evidence of Effect Modification of Graft-Versus-Leukemia Effect of Cytomegalovirus By Alemtuzumab in Myeloid Malignancies Undergoing Unrelated Donor Transplantation

Several studies have suggested a beneficial effect of CMV seropositivity and or reactivation on relapse risk after allogeneic hematopoietic cell transplantation (HCT) in myeloid malignancies. Inability to replicate this finding in T cell depleted HCT is suggestive of a potential effect modification between TCD and CMV in this setting, but this has not been addressed in previously published studies.We have retrospectively analyzed transplant outcomes in 192 patients with myeloid malignancies who have undergone unrelated donor HCT at our center during January 2006 –November 2013. Among this 111 patients received in vivo TCD with low dose (30 mg) alemtuzumab and 81 patients received non-TCD transplants. Recipients were CMV seropositive in 57% of TCD transplants and 59% of non-TCD transplants.Analysis showed a significant effect modification (p=0.03 for interaction) between alemtuzumab and CMV serostatus on relapse risk, and stratified analysis based on recipient CMV status showed inferior outcomes with alemtuzumab in CMV seropositive recipients but not in CMV seronegative recipients. In CMV seropositive recipients alemtuzumab was an independent predictor of higher relapse (Hazard Ratio=13.95, p=0.008), inferior relapse free survival (HR=2.30, p=0.002), and inferior overall survival (HR= 2.04, p=0.008).There was no difference in NRM between CMV seropositive and CMV seronegative groups, or between TCD and non-TCD transplants.These findings suggest the presence of an effect modification by TCD on CMV’s effect on relapse, resulting in inferior transplant outcomes with low dose Alemtuzumab in CMV seropositive recipients, but not in seronegative recipients. [Display omitted] DisclosuresOff Label Use: Alemtuzumab for GVHD prophylaxis.

Frontline low-dose alemtuzumab with fludarabine and cyclophosphamide prolongs progression-free survival in high-risk CLL

AbstractThe randomized Haemato Oncology Foundation for Adults in The Netherlands 68 phase 3 trial compared front-line chemotherapy with chemotherapy plus the CD52 monoclonal antibody alemtuzumab for high-risk chronic lymphocytic leukemia, defined as at least 1 of the following: unmutated immunoglobulin heavy chain genes, deletion 17p or 11q, or trisomy 12. Fit patients were randomized to receive either 6 28-day cycles of oral FC chemotherapy (days 1 through 3: fludarabine 40 mg/m2 per day and cyclophosphamide 250 mg/m2 per day: n = 139) or FC plus subcutaneous alemtuzumab 30 mg day 1 (FCA, n = 133). FCA prolonged the primary end point, progression-free survival (3-year progression-free survival 53 vs 37%, P = .01), but not the secondary end point, overall survival (OS). However, a post hoc analysis showed that FCA increased OS in patients younger than 65 years (3-year OS 85% vs 76%, P = .035). FCA also increased the overall response rate (88 vs 78%, P = .036), and the bone marrow minimal residual disease–negative complete remission rate (64% vs 43%, P = .016). Opportunistic infections were more frequent following FCA, but without an increase in treatment related mortality (FCA: 3.8%, FC: 4.3%). FCA improves progression-free survival in high-risk chronic lymphocytic leukemia. As anticipated, FCA is more immunosuppressive than FC, but with due vigilance, does not lead to a higher treatment-related mortality. This study was registered at www.trialregister.nl as trial no. NTR529.

Reduced-intensity conditioning and HLA-matched haemopoietic stem-cell transplantation in patients with chronic granulomatous disease: a prospective multicentre study

In chronic granulomatous disease allogeneic haemopoietic stem-cell transplantation (HSCT) in adolescents and young adults and patients with high-risk disease is complicated by graft-failure, graft-versus-host disease (GVHD), and transplant-related mortality. We examined the effect of a reduced-intensity conditioning regimen designed to enhance myeloid engraftment and reduce organ toxicity in these patients. This prospective study was done at 16 centres in ten countries worldwide. Patients aged 0-40 years with chronic granulomatous disease were assessed and enrolled at the discretion of individual centres. Reduced-intensity conditioning consisted of high-dose fludarabine (30 mg/m(2) [infants <9 kg 1·2 mg/kg]; one dose per day on days -8 to -3), serotherapy (anti-thymocyte globulin [10 mg/kg, one dose per day on days -4 to -1; or thymoglobuline 2·5 mg/kg, one dose per day on days -5 to -3]; or low-dose alemtuzumab [<1 mg/kg on days -8 to -6]), and low-dose (50-72% of myeloablative dose) or targeted busulfan administration (recommended cumulative area under the curve: 45-65 mg/L × h). Busulfan was administered mainly intravenously and exceptionally orally from days -5 to -3. Intravenous busulfan was dosed according to weight-based recommendations and was administered in most centres (ten) twice daily over 4 h. Unmanipulated bone marrow or peripheral blood stem cells from HLA-matched related-donors or HLA-9/10 or HLA-10/10 matched unrelated-donors were infused. The primary endpoints were overall survival and event-free survival (EFS), probabilities of overall survival and EFS at 2 years, incidence of acute and chronic GVHD, achievement of at least 90% myeloid donor chimerism, and incidence of graft failure after at least 6 months of follow-up. 56 patients (median age 12·7 years; IQR 6·8-17·3) with chronic granulomatous disease were enrolled from June 15, 2003, to Dec 15, 2012. 42 patients (75%) had high-risk features (ie, intractable infections and autoinflammation), 25 (45%) were adolescents and young adults (age 14-39 years). 21 HLA-matched related-donor and 35 HLA-matched unrelated-donor transplants were done. Median time to engraftment was 19 days (IQR 16-22) for neutrophils and 21 days (IQR 16-25) for platelets. At median follow-up of 21 months (IQR 13-35) overall survival was 93% (52 of 56) and EFS was 89% (50 of 56). The 2-year probability of overall survival was 96% (95% CI 86·46-99·09) and of EFS was 91% (79·78-96·17). Graft-failure occurred in 5% (three of 56) of patients. The cumulative incidence of acute GVHD of grade III-IV was 4% (two of 56) and of chronic graft-versus-host disease was 7% (four of 56). Stable (≥90%) myeloid donor chimerism was documented in 52 (93%) surviving patients. This reduced-intensity conditioning regimen is safe and efficacious in high-risk patients with chronic granulomatous disease. None.

Low-dose alemtuzumab vs. standard policy for prevention of graft-versus-host disease in unrelated and related allogeneic stem cell transplantation—a matched pair analysis

Antibody-mediated in vivo T cell depletion is common prior to unrelated (URD) or mismatched allogeneic stem cell transplantation (alloSCT) and optional in HLA-identical sibling (FAM) alloSCT. While anti-thymocyte globulin (ATG) is the current standard, alemtuzumab is an alternative. The optimal dose of alemtuzumab has not been defined. This retrospective analysis compares low-dose alemtuzumab with ATG in URD alloSCT and with no antibody in FAM alloSCT. Twenty-eight patients treated with alemtuzumab (10mg; HLA mismatch, 20mg) were matched to 28 patients who have either received ATG (URD) or no antibody (noAB) according to disease, disease stage, age, transplant type and risk state. Both groups were compared for engraftment, outcome, disease-free (DFS) and overall survival (OS), graft-versus-host disease (GvHD), freedom from GvHD (ffGvHD) and transplant-related mortality (TRM). No significant differences were found between the groups for leukocyte engraftment, GvHD, ffGvHD, TRM, DFS and OS. There was a trend for reduction of cGvHD by alemtuzumab (p = 0.05). A transplant-type stratified subanalysis consolidated equivalency of alemtuzumab and ATG in URD-SCT and indicates possible superiority of low-dose alemtuzumab compared to noAB in FAM-SCT. Low-dose alemtuzumab, as part of conditioning regimen prior to alloSCT, is safe and comparable to standard ATG. Prospective trials, particularly comparing alemtuzumab vs. noAB in FAM alloSCT, should be conducted.

Plasma alemtuzumab levels in patients with chronic lymphocytic leukemia treated with alemtuzumab combined with chemotherapy reflect the efficacy of the treatment: a hypothesis

In the HOVON68 trial comparing subcutaneous low-dose alemtuzumab (LD-A) used together with fludarabine (F) and cyclophosphamide (C) with FC alone in high-risk chronic lymphocytic leukemia (CLL), LD-AFC resulted in significantly more clinical and molecular responses than FC, but also in more opportunistic infections. In a subgroup analysis of alemtuzumab trough levels during treatment by a sensitive enzyme-linked immunosorbent assay (ELISA) method, detectable levels were found in 4/6 complete and 0/3 partial responders. A relationship between alemtuzumab plasma levels, response and duration of lymphocytopenia was evident. We hypothesize that following combination therapy, the response may not be a function of the alemtuzumab levels, but the opposite, that plasma alemtuzumab levels are a function of the efficacy of the entire treatment, and the fewer leukemic target cells that are remaining, the higher are the levels of plasma alemtuzumab. This concept may well provide a guide for alemtuzumab dosage in future trials.

Immune Thrombocytopenia Associated to Low-Dose Alemtuzumab Therapy in Chronic Lymphocytic Leukemia: A Single Retrospective Center Experience

AbstractAbstract 4598Immune thrombocytopenia (ITP) is a common autoimmune complication in chronic lymphocytic leukemia (CLL), occurring in up to 5% of patients. The occurrence of alemtuzumab-associated ITP have been rarely reported in CLL and it has never been reported so far as a significant event complicating alemtuzumab treatment in clinical trials. Recently, a new distinctive form of secondary ITP occurring in 6 out of 215 patients with relapsing-remitting multiple sclerosis treated with alemtuzumab in a randomized, controlled phase II trial has been reported (Cuker et al, Blood 2011).We investigated the incidence of ITP in a cohort of 64 consecutive patients treated with low-dose alemtuzumab for relapsed/refractory CLL from 2003 to 2010. Subcutaneous alemtuzumab was administered at the dose of 10 mg three times a week, up to 18 weeks.ITP was documented in 12/64 patients: in 3 patients (4.7%) ITP developed before alemtuzumab treatment and no relapses of the autoimmune disorder were observed during the treatment; in 9 patients (14.8%, with an incidence of 5.7 events/100 patient-year) ITP developed after alemtuzumab treatment. Median time to ITP from initial alemtuzumab exposure was 12 months (range 1–42 months). Concomitant hemolytic anemia (Evans syndrome) was observed in one patient. At ITP onset, median platelet counts were 11×109/L (range 3–70) and anti-platelet antibodies (Capture P® Method, ImmucorGamma, Norcross GA, USA) were found in 7 of the 8 patients tested. No patients showed severe or life-threatening bleeding. Three of nine patients who developed ITP after alemtuzumab therapy, experienced CLL progression requiring chemo-immunotherapy after 3, 4 and 13 months from ITP onset, respectively. One patient achieved a partial remission of CLL with ITP resolution, while the other two died of disease progression. In the remaining six cases, ITP was not associated with disease progression and was treated with corticosteroids and/or intravenous immunoglobulins. Five patients achieved normal platelet counts, while one patient did not respond.Low-dose alemtuzumab (theoretical cumulative dose 540 mg, equal to half of the classic cumulative dose and one-third of the individual dose) is an effective, safe and well tolerated treatment for CLL, as reported by several recent studies (Cortelezzi et al, Leukemia 2009; Brit J Haematol 2011). In our cohort of CLL patients treated with alemtuzumab, the incidence of ITP was 14.8% that is almost three times higher than previously reported in CLL. These data may indicate a role of T-lymphocyte dysregulation induced by alemtuzumab in the pathogenesis of ITP. Our data also suggested the importance of monitoring platelet counts during follow-up in patients treated with low-dose alemtuzumab for both haematological and non-haematological diseases. Disclosures:No relevant conflicts of interest to declare.

Low‐dose alemtuzumab‐associated immune thrombocytopenia in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is frequently complicated during its course by autoimmune disorders (from 2 to 12% of cases), such as autoimmune hemolytic anemia (AIHA) and immune thrombocytopenic purpura (ITP). In particular, ITP has been reported in about 2–5% of CLL population. Recently, Cuker et al. reported the occurrence of ITP in 6/216 patients with relapsing-remitting multiple sclerosis in a phase 2 clinical trial of annual alemtuzumab. Alemtuzumab is an anti-CD52 monoclonal antibody used in CLL both as first-line treatment and in relapsed/refractory patients. We evaluated a cohort of 64 consecutive patients affected by relapsed-refractory CLL treated with low-dose alemtuzumab and we observed a incidence of ITP higher than predicted. Our data, associated with the report of Cuker et al., seem to suggest an important role of alemtuzumab in the pathogenesis of ITP which could be related to its induced dysregulation of T-lymphocyte activity.

Therapy of Steroid-Refractory Chronic GVHD with Subcutaneous Low-Dose Alemtuzumab and Rituximab Combination Is Effective and Safe

Therapy of Steroid-Refractory Chronic GVHD with Subcutaneous Low-Dose Alemtuzumab and Rituximab Combination Is Effective and Safe