Abhinav Deol

Role of donor lymphocyte infusions in relapsed hematological malignancies after stem cell transplantation revisited

BACKGROUND Treatment of relapsed hematological malignancies after an allogeneic peripheral blood stem cell transplant (SCT) is challenging. Donor lymphocyte infusion (DLI) from the stem cell donor is an attractive clinical option to salvage this group of patients. METHODS We reviewed the important studies looking at donor lymphocyte infusion as a therapy for the treatment of hematological disorders that are either refractory to or have relapsed after allogeneic SCT. RESULTS The response to DLI is dependent upon type of disease, dose of infused lymphocytes, and the development of graft vs. host disease (GvHD). The best response rates are seen in patients with chronic myeloid leukemia (CML) followed by patients with lymphomas, multiple myeloma and acute leukemias, respectively. The responses in patients with CML are durable whereas durable responses in other diseases are rare. CONCLUSIONS Given the development of new drugs to treat some hematological diseases, DLI has taken a backseat. New modalities to target the infused cells to the tumor and new approaches to reduce GvHD that will augment the graft vs. leukemia/lymphoma (GvL) effect and decrease the injury to normal host tissues need to be developed. Understanding the factors and mechanisms that differentiate the GvL effect from GvHD will help in the development of newer treatment modalities.

Reduced intensity conditioning is superior to nonmyeloablative conditioning for older chronic myelogenous leukemia patients undergoing hematopoietic cell transplant during the tyrosine kinase inhibitor era

Tyrosine kinase inhibitors (TKIs) and reduced intensity conditioning (RIC)/nonmyeloablative (NMA) conditioning hematopoietic cell transplants (HCTs) have changed the therapeutic strategy for chronic myelogenous leukemia (CML) patients. We analyzed post-HCT outcomes of 306 CML patients reported to the Center for International Blood and Marrow Transplant Research aged 40 years and older undergoing RIC/NMA HCT from 2001 to 2007: 117 (38%) aged 40 to 49 years, 119 (39%) 50 to 59 years, and 70 (23%) 60 years or older. The majority (74%) had treatment with imatinib before HCT. At HCT, most patients aged 40 to 49 years were in chronic phase (CP) 1 (74%), compared with 31% aged 60 years or older. Siblings were donors for 56% aged 40 to 49 years; older cohorts had more unrelated donors. The majority received peripheral blood grafts and RIC across all age groups. 3 year overall survival (54%, 52%, and 41%), day + 100 grade II-IV acute GVHD (26%, 32%, and 32%), chronic GVHD (58%, 51%, and 43%), and 1-year treatment-related mortality (18%, 20%, and 13%) were similar across ages. The 3-year relapse incidence (36%, 43%, and 66%) and disease-free survival (35%, 32%, and 16%) were inferior in the oldest cohort. Importantly, for CP1 patients, relapse and disease-free survival were similar across age cohorts. Allogeneic RIC HCT for older patients with CML can control relapse with acceptable toxicity and survival in TKI-exposed CML, especially if still in CP1.

Pediatric-inspired therapy compared to allografting for Philadelphia chromosome-negative adult ALL in first complete remission

For adults with Philadelphia chromosome‐negative (Ph−) acute lymphoblastic leukemia (ALL) in first complete remission (CR1), allogeneic hematopoietic cell transplantation (HCT) is an established curative strategy. However, pediatric‐inspired chemotherapy may also offer durable leukemia‐free survival in the absence of HCT. We compared 422 HCT recipients aged 18–50 years with Ph‐ALL in CR1 reported to the CIBMTR with an age‐matched concurrent cohort of 108 Ph− ALL CR1 patients who received a Dana‐Farber Consortium pediatric‐inspired non‐HCT regimen. At 4 years of follow‐up, incidence of relapse after HCT was 24% (95% CI 19–28) versus 23% (95% CI 15–32) for the non‐HCT (chemo) cohort (P=0.97). Treatment‐related mortality (TRM) was higher in the HCT cohort [HCT 37% (95% CI 31–42) versus chemo 6% (95% CI 3–12), P<0.0001]. DFS in the HCT cohort was 40% (95% CI 35–45) versus 71% (95% CI 60–79) for chemo, P<0.0001. Similarly, OS favored chemo [HCT 45% (95% CI 40–50)] versus chemo 73% [(95% CI 63–81), P<0.0001]. In multivariable analysis, the sole factor predictive of shorter OS was the administration of HCT [hazard ratio 3.12 (1.99–4.90), P<0.0001]. For younger adults with Ph− ALL, pediatric‐inspired chemotherapy had lower TRM, no increase in relapse, and superior overall survival compared to HCT. Am. J. Hematol. 91:322–329, 2016.

Allotransplantation for patients age ≥40 years with non-Hodgkin lymphoma: encouraging progression-free survival.

Non-Hodgkin lymphoma (NHL) disproportionately affects older patients, who do not often undergo allogeneic hematopoietic cell transplantation (HCT). We analyzed Center for International Blood and Marrow Transplant Research data on 1248 patients age ≥40 years receiving reduced-intensity conditioning (RIC) or nonmyeloablative (NMA) conditioning HCT for aggressive (n = 668) or indolent (n = 580) NHL. Aggressive lymphoma was more frequent in the oldest cohort 49% for age 40 to 54 versus 57% for age 55 to 64 versus 67% for age ≥65; P = .0008). Fewer patients aged ≥65 had previous autografting (26% versus 24% versus 9%; P = .002). Rates of relapse, acute and chronic GVHD, and nonrelapse mortality (NRM) at 1 year post-HCT were similar in the 3 age cohorts (22% [95% confidence interval (CI), 19% to 26%] for age 40 to 54, 27% [95% CI, 23% to 31%] for age 55 to 64, and 34% [95% CI, 24% to 44%] for age ≥65. Progression-free survival (PFS) and overall survival (OS) at 3 years was slightly lower in the older cohorts (OS: 54% [95% CI, 50% to 58%] for age 40 to 54; 40% [95% CI, 36% to 44%] for age 55 to 64, and 39% [95% CI, 28% to 50%] for age ≥65; P < .0001). Multivariate analysis revealed no significant effect of age on the incidence of acute or chronic GVHD or relapse. Age ≥55 years, Karnofsky Performance Status <80, and HLA mismatch adversely affected NRM, PFS, and OS. Disease status at HCT, but not histological subtype, was associated with worse NRM, relapse, PFS, and OS. Even for patients age ≥55 years, OS still approached 40% at 3 years, suggesting that HCT affects long-term remission and remains underused in qualified older patients with NHL.

High Incidence of Severe Acute Graft-Versus-Host Disease with Tacrolimus and Mycophenolate Mofetil in a Large Cohort of Related and Unrelated Allogeneic Transplantation Patients

Both acute and chronic graft-versus-host disease (GVHD) are major causes of morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation (AHSCT). The optimal pharmacological regimen for GVHD prophylaxis is unclear, but combinations of a calcineurin inhibitor (cyclosporin or tacrolimus [Tac]) and an antimetabolite (methotrexate or mycophenolate mofetil [MMF]) are typically used. We retrospectively evaluated the clinical outcomes of 414 consecutive patients who underwent AHSCT from sibling (SD) or unrelated donors (UD) with Tac/MMF combination, between January 2005 and August 2010. The median follow-up was 60 months. Less than one third of the patients received a reduced-intensity chemoregimen. The incidence of grades III and IV acute GVHD was 22.3% and 36.5% in SD and UD groups, respectively (P = .0007). The incidence of chronic GVHD was 47.1% and 52.7% in the SD and UD groups, respectively. Nonrelapse mortality (NRM) at 60 months was 33.3% and 46.5% in the SD and UD groups, respectively (P = .0016). The incidence of relapse was 22.4% for UD and 28.8% for SD. Five-year overall survival was 43% and 34% in the SD and UD groups, respectively (P = .0183). GVHD was the leading cause of death for the entire cohort. Multivariable analysis showed that 8/8 HLA match, patients age < 60, and low-risk disease were associated with better survival. The use of Tac/MMF for GVHD prophylaxis was associated with a relatively high incidence of severe acute GVHD and NRM in AHSCT from sibling and unrelated donors.

Incidence, Risk Factors, and Outcome of Cytomegalovirus Viremia and Gastroenteritis in Patients with Gastrointestinal Graft-versus-Host Disease

Gastrointestinal (GI) graft-versus-host disease (GVHD) is one of the most common causes of morbidity and mortality after allogeneic stem cell transplantation. In addition, cytomegalovirus (CMV) infection of the gastrointestinal tract can complicate the post-transplantation course of these patients and it can be difficult to differentiate the 2 diagnoses given that they can present with similar symptoms. We retrospectively analyzed 252 patients who were diagnosed with GI GVHD to evaluate the incidence, risk factors, and outcomes of CMV viremia and CMV gastroenteritis in these patients. The median age at the time of transplantation was 51 years, 35% were related donor transplantations, and 65% were unrelated donor transplantations. A total of 114 (45%) patients developed CMV viremia at a median of 34 days (range, 14 to 236 days) after transplantation. Only recipient CMV IgG serostatus was significantly associated with development of CMV viremia (P < .001). The incidence of CMV viremia with relation to donor (D) and recipient (R) CMV serostatus subgroups was as follows: D+/R+, 73%; D-/R+, 67%; D+/R-, 19%; and D-/R-, 0. A total of 31 patients were diagnosed with a biopsy-proven CMV gastroenteritis; 2 patients had evidence of CMV gastroenteritis and GVHD on the first biopsy and 29 on the second biopsy. Median time to development of CMV gastroenteritis was 52 days (range, 19 to 236 days) after transplantation. Using death as a competing risk, the cumulative incidence of CMV gastroenteritis at 1 year was 16.4%. The incidence of CMV gastroenteritis in relation to the donor/recipient serostatus was as follows: D+/R+, 22%; D-/R+, 31%; D+/R-, 12%; and D-/R-, 0. Median follow-up time for the 252 patients was 35.4 (95% CI 23.8 to 44.8) months. The estimated overall survival rate at 1 and 2 years was .45 (95% confidence interval [CI], .39 to .52) and .39 (95% CI, .33 to .46), respectively. Of the examined variables, those related to the overall survival were maximal clinical GVHD grade (P < .001) and development of CMV gastroenteritis (P = .008). Development of CMV viremia was not associated with increased mortality. In conclusion, CMV gastroenteritis is common complication in patients with GI GVHD and can adversely affect the prognosis.

CD20-Targeted T Cells after Stem Cell Transplantation for High Risk and Refractory Non-Hodgkin's Lymphoma

A phase I trial of infusing anti-CD3 × anti-CD20 bispecific antibody (CD20Bi) armed activated T cells (aATC) was conducted in high-risk/refractory non-Hodgkins lymphoma patients to determine whether aATC infusions are safe, affect immune recovery, and induce an antilymphoma effect. Ex vivo expanded ATC from 12 patients were armed with anti-CD20 bispecific antibody, cryopreserved, and infused after autologous stem cell transplantation (SCT). Patients underwent SCT after high-dose chemotherapy, and aATC infusions were started on day +4. The patients received 1 infusion of aATC per week for 4 weeks after SCT with doses of 5, 10, 15, and 20 × 10(9). aATC infusions were safe and did not impair engraftment. The major side effects were chills, fever, hypotension, and fatigue. The mean number of IFN-γ Enzyme-linked Immunosorbent Spots (ElSpots) directed at CD20 positive lymphoma cells (DAUDI, P = .0098) and natural killer cell targets (K562, P < .0051) and the mean specific cytotoxicity directed at DAUDI (P = .037) and K562 (P = .002) from pre-SCT to post-SCT were significantly higher. The increase in IFN-γ EliSpots from pre-SCT to post-SCT in patients who received armed ATC after SCT were significantly higher than those in patients who received SCT alone (P = .02). Serum IL-7, IL-15, Macrophage inflammatory protein (MIP)-1 beta, IP-10, MIP-1α, and Monokine induced by gamma interferone increased within hours after infusion. Polyclonal and specific antibodies were near normal 3 months after SCT. aATC infusions were safe and increased innate and specific antilymphoma cell immunity without impairing antibody recovery after SCT.

Ipilimumab augments antitumor activity of bispecific antibody-armed T cells

BackgroundIpilimumab is an antagonistic monoclonal antibody against cytotoxic T-lymphocyte antigen-4 (CTLA-4) that enhances antitumor immunity by inhibiting immunosuppressive activity of regulatory T cells (Treg). In this study, we investigated whether inhibiting Treg activity with ipilimumab during ex vivo T cell expansion could augment anti-CD3-driven T cell proliferation and enhance bispecific antibody (BiAb)-redirected antitumor cytotoxicity of activated T cells (ATC).MethodsPBMC from healthy individuals were stimulated with anti-CD3 monoclonal antibody with or without ipilimumab and expanded for 10-14 days. ATC were harvested and armed with anti-CD3 x anti-EGFR BiAb (EGFRBi) or anti-CD3 x anti-CD20 BiAb (CD20Bi) to test for redirected cytotoxicity against COLO356/FG pancreatic cancer cell line or Burkitt’s lymphoma cell line (Daudi).ResultsIn PBMC from healthy individuals, the addition of ipilimumab at the initiation of culture significantly enhanced T cell proliferation (p = 0.0029). ATC grown in the presence of ipilimumab showed significantly increased mean tumor-specific cytotoxicity at effector:target (E:T) ratio of 25:1 directed at COLO356/FG and Daudi by 37.71% (p < 0.0004) and 27.5% (p < 0.0004), respectively, and increased the secretion of chemokines (CCL2, CCL3, CCL4,CCL5, CXCL9, and granulocyte-macrophage colony stimulating factor(GM-CSF)) and cytokines (IFN-γ, IL-2R, IL-12, and IL-13), while reducing IL-10 secretion.ConclusionsExpansion of ATC in the presence of ipilimumab significantly improves not only the T cell proliferation but it also enhances cytokine secretion and the specific cytotoxicity of T cells armed with bispecific antibodies.

Multiple infusions of CD20-targeted T cells and low-dose IL-2 after SCT for high-risk non-Hodgkin's lymphoma: a pilot study.

A pilot phase I clinical trial involving 15 infusions of anti-CD3 × anti-CD20 bispecific Ab (CD20Bi)-armed anti-CD3-activated T cells (aATC) and low-dose IL-2 was conducted in three non-Hodgkin’s lymphoma (NHL) patients (two high-risk and one refractory) after autologous SCT. The feasibility of T-cell expansion, safety of aATC infusions, cytotoxic immune responses and trafficking of aATC were evaluated. Three NHL patients received 15 infusions of 5 × 109 aATC (three infusions/week for 3 weeks and one infusion/week for 6 weeks) between days 1 and 65 after SCT with IL-2. There were no dose-limiting toxicities. Chills, fever, hypotension and malaise were the common side effects. Engraftment was delayed in one patient with a low stem cell dose. CD20Bi aATC infusions induced specific cytotoxicity directed at lymphoma targets. Endogenous peripheral blood mononuclear cells from two patients mediated anti-lymphoma cytotoxicity above preSCT background (P<0.001). 111In labeled aATC trafficked to the lungs at 1 h and accumulated in the liver and bone marrow after 24 h. aATC infusions given over 69 days in combination with IL-2 were safe, did not inhibit engraftment, and induced endogenous cytotoxic responses directed at lymphoma targets.

Long-term follow up of patients proceeding to transplant using plerixafor mobilized stem cells and incidence of secondary myelodysplastic syndrome/AML.

We report the long-term follow up of 49 patients (pts) enrolled on plerixafor compassionate use protocol. Thirty-seven pts (76%) had failed one previous mobilization attempt, while 12 (24%) had failed two or more previous attempts. Using the combination of plerixafor and granulocyte colony-stimulating factor, we collected⩾2.5 × 106 CD34+cells/kg in 33 pts (67%). Forty-three of the 49 pts proceeded to an auto-SCT (ASCT). The median days to WBC and platelet engraftment were 11 (range, 9–13 days) and 16 (range, 11–77 days) days post ASCT, respectively. The median WBC count, Hb and platelet counts 1 year after ASCT were 4.7 × 109/L, 12.2 g/dL and 109 × 109/L, respectively. With median follow up of 42 months (range <1–54 months), 21 pts had evidence of disease progression. Five pts developed myelodysplastic syndrome (MDS)/AML at median of 29 months post ASCT. The cumulative incidence of MDS/AML at 42 months was 17% (95% confidence interval, 6 to 32%). Development of secondary MDS/AML in pts proceeding to ASCT after plerixafor mobilization needs to be studied further in a larger cohort.