Addition Of Alemtuzumab Research Articles

Effect of alemtuzumab-based T-cell depletion on graft compositional change in vitro and immune reconstitution early after allogeneic stem cell transplantation

Background aimsTo reduce the risk of graft-versus-host disease (GVHD) after allogeneic stem cell transplantation (alloSCT), T-cell depletion (TCD) of grafts can be performed by the addition of alemtuzumab (ALT) “to the bag” (in vitro) before transplantation. In this prospective study, the authors analyzed the effect of in vitro incubation with 20 mg ALT on the composition of grafts prior to graft infusion. Furthermore, the authors assessed whether graft composition at the moment of infusion was predictive for T-cell reconstitution and development of GVHD early after TCD alloSCT. MethodsSixty granulocyte colony-stimulating factor-mobilized stem cell grafts were obtained from ≥9/10 HLA-matched related and unrelated donors. The composition of the grafts was analyzed by flow cytometry before and after in vitro incubation with ALT. T-cell reconstitution and incidence of severe GVHD were monitored until 12 weeks after transplantation. ResultsIn vitro incubation of grafts with 20 mg ALT resulted in an initial median depletion efficiency of T-cell receptor (TCR) α/β T cells of 96.7% (range, 63.5–99.8%), followed by subsequent depletion in vivo. Graft volumes and absolute leukocyte counts of grafts before the addition of ALT were not predictive for the efficiency of TCR α/β T-cell depletion. CD4pos T cells were depleted more efficiently than CD8pos T cells, and naive and regulatory T cells were depleted more efficiently than memory and effector T cells. This differential depletion of T-cell subsets was in line with their reported differential CD52 expression. In vitro depletion efficiencies and absolute numbers of (naive) TCR α/β T cells in the grafts after ALT incubation were not predictive for T-cell reconstitution or development of GVHD post- alloSCT. ConclusionsThe addition of ALT to the bag is an easy, fast and generally applicable strategy to prevent GVHD in patients receiving alloSCT after myeloablative or non-myeloablative conditioning because of the efficient differential depletion of donor-derived lymphocytes and T cells.

Alemtuzumab Added to CHOP for Treatment of Peripheral T-Cell Lymphoma (PTCL) in Previously Untreated Young and Elderly Patients: Pooled Analysis of the International ACT-1/2 Phase III Trials

Background: Standard treatment in PTCL pts is unsatisfactory due to a high rate of early progression. Alemtuzumab (A), a monoclonal anti CD52 antibody, has demonstrated efficacy in relapsed PTCL pts. The results of the final analyses of the ACT-1 phase III and the ACT-2 phase III trial, comparing standard CHOP to A-CHOP showed higher response rates, but did not yield significant differences in EFS, PFS and OS in both previously untreated young and elderly patients, but the planned sample sizes could not be reached due to low recruitment. We undertook a planned pooled analysis of both ACT trials comparing CHOP with A-CHOP to increase statistical power.Patients and Methods: Between 2007 and 2013, 252 pts from Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Norway, Poland, Portugal, Sweden and The Netherlands were randomized to receive either 6 cycles CHOP or A-CHOP at 14 day intervals. The planned pooled analysis was performed to compare patient outcome adding A to CHOP with patients treated with CHOP alone. Primary endpoint within ACT-1 and ACT-2 trial was the 3 years event free survival (EFS), secondary endpoints were progression free survival (PFS) and overall survival (OS). EFS is defined as the time from randomization to disease progression, start of salvage treatment, additional (unplanned) treatments, relapse, or death of any cause.Results: 252 pts were randomized (ACT-1: 136; ACT-2: 116). Five patients received no study treatment; therefore, 247 pts were analyzed (CHOP: 124; A-CHOP: 123). Median age was 61 years. 62% were male. Histologies were 33% AITL, 34% PTCL NOS, 33% other subtypes. In the pooled data set, the two treatment groups were comparable. Infections grade ≥3 occurred more often in patients treated with Alemtuzumab (A-CHOP: 55% [95% CI: 45% - 64%] vs. CHOP 23% [16% - 32%]; p<0.001). Complete remissions were achieved in 56% [47% - 65%] of A-CHOP and 43% [34% - 52%] of CHOP pts (p=0.036). However, EFS (A-CHOP at 3 yrs: 32% [23% - 40%] vs. CHOP 25% [17% - 33%]; p=0.159), PFS (33% [25% - 42%] vs. 27% [19% - 35%]; p=0.220) and OS (46% [37% - 55%] vs. 53% [44% - 62%]; p=0.332) showed no significant differences. Multivariate analyses, adjusted for IPI factors, bulky disease and gender, confirmed these results (hazard ratio HREFS: 0.8 ([95% CI: 0.6 - 1.1]; p=0.196), HRPFS: 0.8 ([95% CI: 0.6 - 1.1]; p=0.246), HROS: 1.2 ([95% CI: 0.8 - 1.6]; p=0.370). Male gender (HR 2.5), ECOG > 1 (HR 2.1) and bulky disease (HR 2.1) were the most prominent unfavorable risk factors for EFS. With the sample size of 247 pts the power for detecting the planned EFS difference of 15% was 74%.Conclusion: Adding Alemtuzumab to CHOP increased the rate of CR in PTCL patients, albeit at the costs of higher treatment related toxicity. Addition of Alemtuzumab did not improve EFS, PFS, or OS. Female gender is associated with a significantly better prognosis. This is the largest prospective dataset collected for PTCL.Supported by Federal Ministry of Research BMBF FKZ 01KG0705 and unrestricted research grants by Genzyme-Sanofi and AMGEN DisclosuresNo relevant conflicts of interest to declare.

Phase I\u2013II study of lenalidomide and alemtuzumab in refractory chronic lymphocytic leukemia (CLL): effects on T cells and immune checkpoints

This phase I–II study explored safety, immunomodulatory and clinical effects of lenalidomide (weeks 1–16) and alemtuzumab (weeks 5–16) in 23 patients with refractory chronic lymphocytic leukemia. Most patients had Rai stage III/IV disease and were heavily pretreated (median 4 prior therapies), and 61% had del(17p)/del(11q). Eleven of 19 evaluable patients (58%) responded, with a median response duration of 12 months (1–29+); time to progression was short in non-responders. Lenalidomide had a narrow therapeutic dose range, 2.5 mg/day was not efficient, and maximum tolerated dose was 5 mg/day. Grade 3–4 neutropenia and thrombocytopenia occurred in 84 and 55%, 30% had febrile neutropenia, and CMV-reactivation requiring valganciclovir occurred in 30% of patients. The frequency of proliferating (Ki67+) CD8+ T cells was increased at week 4, with further increase in both the CD4+ and CD8+ subsets (p < 0.01 and <0.05), which was accompanied by significant upregulation of HLA-DR after addition of alemtuzumab. Antigen-experienced cells increased at week 4 as the frequency of effector memory cells increased in the CD8+ subset (p < 0.003), while effector cells decreased in both the CD8+ and CD4+ subsets (p < 0.0001 and p < 0.01). The Th1/Th2 balance was unchanged at week 4 but shifted toward a Th2 profile after combination therapy. At end of treatment, the frequency of Th17 and regulatory T cells was reduced (p < 0.01), naïve T cells decreased, and effector memory T cells increased (p < 0.05 and p < 0.01). Granzyme B+ T cells increased at 30-week follow-up (p < 0.05). PD-1 expression was unaffected. In conclusion, low-dose lenalidomide and alemtuzumab induced major perturbations of T cells, including increased proliferative activity and cytotoxic potential.

Infectious Complications After Unrelated Donor Allogeneic Hematopoietic Cell Transplantation With Or Without Alemtuzumab Based In Vivo Lymphocyte Depletion

The addition of alemtuzumab to conditioning may decrease the incidence of graft versus host disease (GVHD) after unrelated donor (URD) allogeneic hematopoietic cell transplantation (alloHCT) but may also contribute to impaired pathogen immunity due to donor lymphocyte depletion. We identified and graded infections occurring within 6 months after URD alloHCT in 78 individuals treated either with (N=40) or without (N=38) alemtuzumab during alloHCT for hematologic cancers. Conditioning included fludarabine (120 mg/m2 total) and cyclophosphamide (4,800 mg/m2 total) over 4 days with either alemtuzumab (100 mg total days -8 to -4) followed by cyclosporine (AC) or with tacrolimus, methotrexate, and sirolimus (TMS) based GVHD prophylaxis. Both groups received a filgrastim mobilized peripheral blood graft from an 8/8 or 7/8 HLA-matched unrelated donor and received GVHD prophylaxis for 180 days. Filgrastim was administered post HCT until neutrophil recovery. Infections were graded according to Cordonnier et al. (Transplantation 2006). Only proven/probable pulmonary fungal episodes by EORT/MSG criteria were included. Infection prophylaxis during the study period included trimethoprim/sulfamethoxazole BID thrice weekly after HCT engraftment and daily acyclovir or valacyclovir. Fungal prophylaxis was fluconazole until day 100 or either micafungin or voriconazole in persons receiving 1+ week of &gt;1 mg/kg/d prednisone or equivalent. Ceftazidime was administered to persons with neutrophil count &lt;500/μL until recovery. Persons were monitored for CMV, adenovirus, toxoplasmosis (in seropositive persons), EBV (after 2009), and HHV-6 with at least weekly blood PCR. CMV was treated with pre-emptive therapy according to published guidelines. Blood aspergillus glactomannin and beta D-glucan assays were obtained when clinically indicated. The use of AC compared to TMS resulted in greater total infections per patient (4.4 versus 2.8, P&lt;0.0001) but similar rates of grade 3 (most serious) infections (0.5 versus 0.6, P=0.49). CMV reactivation in recipient seropositive persons was more common in AC (24/24 AC arm versus 11/24 TMS arm, P&lt;0.0001). The median duration of CMV viremia was 6 weeks in AC versus 2 weeks in TMS (P=0.001). CMV colitis or pneumonitis occurred in 3 persons treated with AC and in 1 person treated with TMS at a mean of 47 days post alloHCT (range 15-121). Bacterial infections per patient in AC and TMS were similar (1.6 versus 1.1, P=0.08). Clostridium difficile colitis was relatively common (10 episodes AC; 11 episodes TMS). HHV-6 infections were similar (24/40 AC versus 16/38 TMS, P=0.16). HHV-6 encephalitis developed in five individuals (3 TMS, 2 AC). The median blood titer at the time CNS involvement was identified was 15,950 copies/mL (0-40,000 copies/mL) and was not predictive on onset of encephalopathy (P=0.6). EBV infection developed in 9 persons in AC and 6 persons in TMS. Three cases of EBV lymphoproliferative disorder occurred in persons treated with AC. An additional three persons in each AC and TMS were treated pre-emptively with rituximab for EBV viremia. Adenovirus infection developed in 4 persons in each TMS and AC. One person treated with AC developed adenoviral colitis. There was one episode of invasive fungal infection in TMS (Candida krusei blood stream infection) and 4 episodes in AC (3 episodes Candida blood stream infection [2 parapsilosis, 1 albicans], one pulmonary aspergillosis). In summary, the use of AC versus TMS resulted greater total infections and CMV infections but with similar bacterial and fungal infection incidence. Weekly monitoring of HHV-6 by blood PCR was ineffective at predicting development of HHV-6 CNS disease. The rate of invasive fungal infections in this cohort was low. Disclosures: No relevant conflicts of interest to declare.

Predictors of Response to Salvage Therapy for Advanced Chronic Lymphocytic Leukemia (ECOG Protocol 2903)

AbstractAbstract 2463The treatment of relapsed/refractory B-Chronic Lymphocytic Leukemia (CLL) is difficult in terms of both inducing meaningful responses and being able to predict clinical outcome. In an attempt to address the latter aspect, we analyzed a battery of prognostic parameters obtained from a cohort of relapsed/refractory CLL patients entered onto ECOG trial E2903. This protocol included 2 steps: an induction phase (step 1) with pentostatin (4 mg/m2), cyclophosphamide (600 mg/m2), and rituximab (375 mg/m2) given every 3 weeks for 6 cycles and a consolidation phase (step 2) where complete responders (CR) were given 4 weeks of subcutaneous (sc) alemtuzumab (30 mg/m2, 3 times a week) or patients attaining partial response (PR), stable or progressive disease were given 18 weeks of sc alemtuzumab. Sixty-five eligible patients were enrolled; median age was 63 yr; male to female ratio of 4:1; median (range) number of prior therapies was 3 (1–7); and there were 16, 7, and 40 patients in Rai 0–1, Rai 2; and Rai 3–4 stages respectively. The median serum β-2 microglobulin was 4 (1–28). The overall response rate for step 1 in this cohort was 46% with 1 complete and 29 partial responses and 38.5% judged as having stable disease. Strict CR criteria, including CT imaging were utilized, demonstrating the infrequency of total response using CT scans. For traditional prognostic parameters, we found that age over 70 yr and high Rai risk stage (3–4) did not preclude a clinical response, but there was a significant difference between responders and non-responders in serum β-2 microglobulin levels (p=0.03). For molecular prognostic parameters, we found that the immunoglobulin variable heavy chain region (IGVH) mutational status did not preclude a lack of clinical response. However, for patients who were ZAP70 negative (−) or CD38 negative (−) these factors were positively associated with clinical response (p=0.046, 0.0005, respectively). The sensitivity in predicting a clinical response was 82% in ZAP70- and 73% in CD38-. In multivariable logistic regression analysis, only CD38 was significantly associated with response (Odds Ratio: 41, p=0.002). When patients were segregated into low (13q- or normal), intermediate (Trisomy 12) and high risk FISH (17p-,) there was no association with clinical outcome. In addition, if patients' CLL cells were unmutated and high risk FISH, there was no reduced clinical response. Of 65 patients included in this analysis, the 2-year overall survival (OS) was 55% (±7%) and the 2-year progression-free survival (PFS) is 25% (± 6.6%). The median follow-up time amongst survivors was 23 (range 6–60) months. The univariable analysis for PFS revealed that the IGVH mutated (2-yr PFS 53% for mutated vs. 18% for unmutated, p=0.037, Figure) and low risk FISH (2-yr PFS 42% for low risk vs. 23% for high risk, p=0.04) were significant. However, only IGVH mutated was significant (HR 0.33, p=0.027) for PFS in multivariable Cox model. In univariable analysis for OS, the combination of age <70 yr and β-2 microglobulin<2 upper limits [UL] was significant (2-yr OS: 68% vs. 39%, p=0.048), whereas only β-2 microglobulin was significant (HR 3.45 for >=2UL vs. <2UL, p=0.02) in multivariable Cox model. A total of 24 patients entered onto step 2 of the consolidation phase, receiving alemtuzumab; 17 patients who were responders from step 1 entered onto the 4 weeks of step 2; and 7 of the non-responders went onto the 18 weeks of step 2. The 2-year OS of these 24 patients was 62% from the date of consolidation phase: 61% for 17 responding patients to PCR and 60% for non responders to PCR (p=0.87). Current conclusions of this study are: (1) heavily pretreated high risk CLL patients may still have a respectable survival with the PCR combination; (2) β-2 microglobulin, ZAP70, and CD38 were important factors associated with response to PCR; (3) both IGVH mutated and FISH were prognostic markers associated with PFS; (4) addition of alemtuzumab may confer comparable survival rates for PCR non responders to the responders; (5) β-2 microglobulin was the only prognostic factor significant for OS. In total this study shows that both traditional and molecular markers can be used to predict clinical outcome for high risk relapsed/ refractory CLL patients treated with chemoimmunotherapy. We anticipate further valuable prognostic information to come from this still accruing study. [Display omitted] Disclosures:Rosen: Genentech: Speakers Bureau.

Comparable Outcome of Alternative Donor and Matched Sibling Donor Hematopoietic Stem Cell Transplant for Children with Acute Lymphoblastic Leukemia in First or Second Remission Using Alemtuzumab in a Myeloablative Conditioning Regimen

HLA-matched sibling donor (MSD) stem cell transplantation can cure>60% of pediatric patients with acute lymphoblastic leukemia (ALL), but <30% of patients will have a sibling donor. Alternative donor (AD) transplantation can be curative but has a higher risk of graft-versus-host disease (GVHD). The addition of alemtuzumab (Campath 1-H) to AD transplants produces in vivo T cell depletion, which may reduce the risk for GVHD. We now report the outcome for 83 children with ALL (41 MSD, 42 AD) undergoing stem cell transplantation in first or second complete remission. All patients received myeloablative conditioning, including cyclophosphamide, cytarabine arabinoside, and total-body irradiation, with alemtuzumab administered to AD recipients. GVHD prophylaxis consisted of a calcineurin inhibitor with either short-course methotrexate or prednisone. Disease-free survival (DFS) for MSD recipients was 72.3% (95% confidence interval [CI], 55.4%-83.6%) versus 62.4% (95% CI, 45.2%-75.4%) for AD recipients. The 100-day mortality was 7.1% in the AD group and 2.4% in the MSD group. Relapse rates were identical (24%). Treatment-related mortality, principally viral infection, explained the difference in survival. For children undergoing stem cell transplantation (SCT) from alternative donors, alemtuzumab with a myeloablative conditioning regimen resulted in DFS comparable to MSD.

Intensive graft-versus-host disease prophylaxis is required after unrelated-donor nonmyeloablative stem cell transplantation

Nonmyeloablative stem cell transplantation (NST) harnesses the graft-versus-tumor effect while minimizing regimen-related toxicity, and can result in donor chimerism and remission. Acute graft-versus-host disease (GVHD) and infections are major complications after sibling NST. Toxicity of unrelated-donor (UD) NST and the most appropriate GVHD prophylaxis in this setting remain poorly defined. We describe 25 patients who received UD-NST conditioned with fludarabine and cyclophosphamide. The first six patients received cyclosporine (Cs) and mycophenolate mofetil (MMF) (n=5) or methotrexate (MTX) (n=1) as GVHD prophylaxis (group 1) and all developed grade III-IV acute GVHD. The next 19 patients received the same conditioning regimen with the addition of alemtuzumab, and all received Cs/MTX post-transplant. Engraftment and donor chimerism were achieved in all but one evaluable patient. In all, 15 patients died: five of six deaths in group 1 were attributable to acute GVHD, while deaths in group 2 were due to infection or progressive disease (P=0.05). The combination of Cs/MMF is inadequate GVHD prophylaxis for UD-NST. The use of Cs, MTX, and alemtuzumab eliminated severe acute GVHD; its impact on response merits further study.

Consolidation with Alemtuzumab in First Remission Induces Pronounced MRD Reduction and Clinical Remissions - Update on a Randomized Phase III Trial of the German CLL Study Group (GCLLSG).

The monoclonal antibody alemtuzumab is known to be effective in combination or alone in patients with late stage chronic lymphocytic leukaemia. Flow cytometric studies on minimal residual disease (MRD) showed the high potency beyond clinical response criteria even in late stage chronic lymphocytic leukaemia (CLL). The aim of the phase III trial of the GCLLSG was to investigate the role of alemtuzumab as consolidation therapy in CLL patients in first clinical remission after fludarabin (F) or F plus cyclophosphamide (FC).Patients in partial or complete clinical remission were randomized to either arm A (alemtuzumab 3 x 30 mg i.v. for up to 12 wks) or no further treatment (arm B). From 21 eligible patients 11 (1CR, 1 nPR, 9PR) were randomized to arm A. All patients received standard infection prophylaxis with famciclovir and trimethoprim/sulfamethoxazole. Before, at 6 and 12 weeks after start of consolidation therapy and regulary during follow up blood and bone marrow samples were send for molecular MRD assessment by allele specific real time PCR. The PCR allowed MRD assessment with a sensitivity of at least 10E-4 in 11 eligible cases.Results: MRD analysis showed clear reduction of CLL content by first line treatment to a median MRD level of 2.2E-3. Short after alemtuzumab treatment all treated patients showed pronounced MRD reduction to a median MRD level of 5.0E-5. During molecular follow-up median MRD level remained below 1E-4 for one year with a tendency to increase afterwards. After a median follow-up of 31.3 months from start of initial treatment occurred one relapse in the treatment arm compared to 7 of 10 in arm B. The median progression free survival (PFS) calculated from start of consolidation therapy was significantly shorter in the control group versus the treatment group (pfs 25.2; p= 0.04). Nevertheless due to severe acute infections (CTC III and IV) this study had to be stopped prematurely.Conlusion: The addition of alemtuzumab as a consolidation regimen after remission induction by F or FC is highly effective and leads to sustained MRD reduction below 10E-4. This translates into significant improved clinical outcome even in this small patient cohort compared to the control group. Encouraged by the molecular responses the GCLLSG initiated a new phase I/II trial as a dose finding study in CLL patients after F based induction of clinical remission.