Improved post-ASCT survival of relapsed/refractory classical Hodgkin lymphoma patients in the era of novel agents

Utilization of novel agents such as brentuximab vedotin (BV) and check-point inhibitors (CI) has increased in patients with relapsed/refractory (r/r) classical Hodgkin Lymphoma (cHL). We conducted a retrospective study of 209 patients who had ASCT for r/r cHL at our institution and compared outcomes of those who had ASCT from 2010-2018 (cohort 2, n = 110) with those who had ASCT between 2000 and 2009 (cohort 1, n = 99). The median OS was 7.6 years for cohort 1 [HR 2.08; 95% CI 1.14-3.80; p = 0.017] and not reached for cohort 2; with 4-year improved OS difference of 15% (80% vs 65%) in cohort 2 vs cohort 1. The median PFS of cohort 1 was 30 months vs 39 months for cohort 2[HR 1.24; 95% CI 0.82-1.88; p = 0.3]. This study highlights improved OS of r/r cHL patients who have received ASCT in the novel agent era due to the exposure to agents such as BV and CIs.

Ciltacabtagene autoleucel, a B-cell maturation antigen-directed chimeric antigen receptor T-cell therapy in patients with relapsed or refractory multiple myeloma (CARTITUDE-1): a phase 1b/2 open-label study

BACKGROUND

CARTITUDE-1 aimed to assess the safety and clinical activity of ciltacabtagene autoleucel (cilta-cel), a chimeric antigen receptor T-cell therapy with two B-cell maturation antigen-targeting single-domain antibodies, in patients with relapsed or refractory multiple myeloma with poor prognosis.

METHODS

This single-arm, open-label, phase 1b/2 study done at 16 centres in the USA enrolled patients aged 18 years or older with a diagnosis of multiple myeloma and an Eastern Cooperative Oncology Group performance status score of 0 or 1, who received 3 or more previous lines of therapy or were double-refractory to a proteasome inhibitor and an immunomodulatory drug, and had received a proteasome inhibitor, immunomodulatory drug, and anti-CD38 antibody. A single cilta-cel infusion (target dose 0·75 × 10⁶ CAR-positive viable T cells per kg) was administered 5-7 days after start of lymphodepletion. The primary endpoints were safety and confirmation of the recommended phase 2 dose (phase 1b), and overall response rate (phase 2) in all patients who received treatment. Key secondary endpoints were duration of response and progression-free survival. This trial is registered with ClinicalTrials.gov, NCT03548207.

FINDINGS

Between July 16, 2018, and Oct 7, 2019, 113 patients were enrolled. 97 patients (29 in phase 1b and 68 in phase 2) received a cilta-cel infusion at the recommended phase 2 dose of 0·75 × 10⁶ CAR-positive viable T cells per kg. As of the Sept 1, 2020 clinical cutoff, median follow-up was 12·4 months (IQR 10·6-15·2). 97 patients with a median of six previous therapies received cilta-cel. Overall response rate was 97% (95% CI 91·2-99·4; 94 of 97 patients); 65 (67%) achieved stringent complete response; time to first response was 1 month (IQR 0·9-1·0). Responses deepened over time. Median duration of response was not reached (95% CI 15·9-not estimable), neither was progression-free survival (16·8-not estimable). The 12-month progression-free rate was 77% (95% CI 66·0-84·3) and overall survival rate was 89% (80·2-93·5). Haematological adverse events were common; grade 3-4 haematological adverse events were neutropenia (92 [95%] of 97 patients), anaemia (66 [68%]), leukopenia (59 [61%]), thrombocytopenia (58 [60%]), and lymphopenia (48 [50%]). Cytokine release syndrome occurred in 92 (95%) of 97 patients (4% were grade 3 or 4); with median time to onset of 7·0 days (IQR 5-8) and median duration of 4·0 days (IQR 3-6). Cytokine release syndrome resolved in all except one with grade 5 cytokine release syndrome and haemophagocytic lymphohistiocytosis. CAR T-cell neurotoxicity occurred in 20 (21%) patients (9% were grade 3 or 4). 14 deaths occurred in the study; six due to treatment-related adverse events, five due to progressive disease, and three due to treatment-unrelated adverse events.

INTERPRETATION

A single cilta-cel infusion at the target dose of 0·75 × 10⁶ CAR-positive viable T cells per kg led to early, deep, and durable responses in heavily pretreated patients with multiple myeloma with a manageable safety profile. The data from this study formed the basis for recent regulatory submissions.

FUNDING

Janssen Research & Development and Legend Biotech.

Prophylactic corticosteroid use in patients receiving axicabtagene ciloleucel for large B-cell lymphoma

ZUMA‐1 (NCT02348216) examined the safety and efficacy of axicabtagene ciloleucel (axi‐cel), an autologous CD19‐directed chimaeric antigen receptor (CAR)‐T cell therapy, in refractory large B‐cell lymphoma. To reduce treatment‐related toxicity, several exploratory safety management cohorts were added to ZUMA‐1. Specifically, cohort 6 investigated management of cytokine release syndrome (CRS) and neurologic events (NEs) with prophylactic corticosteroids and earlier corticosteroid and tocilizumab intervention. CRS and NE incidence and severity were primary end‐points. Following leukapheresis, patients could receive optional bridging therapy per investigator discretion. All patients received conditioning chemotherapy (days −5 through −3), 2 × 10⁶ CAR‐T cells/kg (day 0) and once‐daily oral dexamethasone [10 mg, day 0 (before axi‐cel) through day 2]. Forty patients received axi‐cel. CRS occurred in 80% of patients (all grade ≤2). Any grade and grade 3 or higher NEs occurred in 58% and 13% of patients respectively. Sixty‐eight per cent of patients did not experience CRS or NEs within 72 h of axi‐cel. With a median follow‐up of 8·9 months, objective and complete response rates were 95% and 80% respectively. Overall, prophylactic corticosteroids and earlier corticosteroid and/or tocilizumab intervention resulted in no grade 3 or higher CRS, a low rate of grade 3 or higher NEs and high response rates in this study population.

Post-transplant Cyclophosphamide Versus Thymoglobulin in HLA-Mismatched Unrelated Donor Transplant for Acute Myelogenous Leukemia and Myelodysplastic Syndrome

Limited information is available on the efficacy of post-transplantation cyclophosphamide (PTcy) or thymoglobulin for graft-versus-host disease (GVHD) prophylaxis in mismatched unrelated donor (MMUD) transplants. We retrospectively compared outcomes of 76 adult patients with acute myelogenous leukemia (AML) or myelodysplastic syndrome (MDS) who underwent 7/8 HLA-MMUD transplantation and received either PTcy (50 mg/kg on day 3 and 4) or thymoglobulin (total dose 4.5 mg/kg) for GVHD prophylaxis. In addition, tacrolimus and mycophenolate were used in both groups. Propensity score-based multivariable analyses (PSCA) were performed to adjust confounding effects of patient characteristics between both groups. Between January 2006 and June 2019, 25 patients received PTcy, and 51 received thymoglobulin. Median age of the population was 57 years, 78% of patients had AML, most common graft source was peripheral blood (96%), and 46% received myeloablative conditioning regimens. Median time to neutrophil (15 versus 11 days, P < .001) and platelet engraftment (21 versus 15 days, P = .002) was prolonged in the PTcy group. The cumulative incidence of grade III-IV acute GVHD at day 100 was similar (12% versus 19.6%, P = .38), whereas chronic GVHD at 1 year was lower with PTcy compared to thymoglobulin (16% versus 49%, P = .006). Using PSCA, no difference in survival, relapse, relapse-free survival, and GVHD-free relapse-free survival was seen between groups. However, thymoglobulin was associated with higher incidence of acute (hazard ratio [HR] = 2.63, P = .01) and chronic GVHD (HR = 4.43, P = .03), and non-relapse mortality (HR 3.38, P = .04) compared to PTcy. Our study demonstrated that PTcy resulted in significantly lower rates of acute and chronic GVHD and non-relapse mortality compared to thymoglobulin in 7/8 HLA-MMUD transplants for AML and MDS.

Phase II clinical trial using anti-CD3 × anti-HER2 bispecific antibody armed activated T cells (HER2 BATs) consolidation therapy for HER2 negative (0-2+) metastatic breast cancer

Background

Metastatic human epidermal growth receptor II (HER2) negative breast cancer remains incurable. Our phase I study showed that anti-CD3 × anti-HER2 bispecific antibody armed activated T cells (HER2 BATs) may be effective against HER2-tumors. This phase II trial evaluates the efficacy and immune responses of HER2 BATs given to patients with metastatic HER2-estrogen and/or progesterone receptor positive (HR+) and triple negative breast cancer (TNBC) as immune consolidation after chemotherapy. The primary objective of this study was to increase the traditional median time to progression after failure of first-line therapy of 2–4 months with the secondary endpoints of increasing overall survival (OS) and immune responses.

Methods

HER2- metastatic breast cancer (MBC) patients received 3 weekly infusions of HER2 BATs and a boost after 12 weeks.

Results

This phase II study included 24 HER2-HR+ and 8 TNBC patients who received a mean of 3.75 and 2.4 lines of prior chemotherapy, respectively. Eight of 32 evaluable patients were stable at 4 months after the first infusion. There were no dose limiting toxicities. Tumor markers decreased in 13 of 23 (56.5%) patients who had tumor markers. The median OS was 13.1 (95% CI 8.6 to 17.4), 15.2 (95% CI 8.6 to 19.8), and 12.3 (95% CI 2.1 to 17.8) months for the entire group, HER2-HR+, and TNBC patients, respectively. Median OS for patients with chemotherapy-sensitive and chemotherapy-resistant disease after chemotherapy was 14.6 (9.6–21.8) and 8.6 (3.3–17.3) months, respectively. There were statistically significant increases in interferon-γ immunospots, Th₁ cytokines, Th₂ cytokines, and chemokines after HER2 BATs infusions.

Conclusions

In heavily pretreated HER2-patients, immune consolidation with HER2 BATs after chemotherapy appears to increase the proportion of patients who were stable at 4 months and the median OS for both groups as well as increased adaptive and innate antitumor responses. Future studies combining HER2 BATs with checkpoint inhibitors or other immunomodulators may improve clinical outcomes.

Outcomes of Fludarabine, Melphalan and Total Body Irradiation as a Reduced Intensity Conditioning Regimen in Matched Donor Allogeneic Peripheral Blood Stem Cell Transplantation

Fludarabine 30 mg/m²/d × 5 and melphalan 140 mg/m² × 1 (Flu-Mel140) is a commonly used reduced-intensity conditioning regimen. We hypothesized that addition of 200cGy total body irradiation (TBI) to Flu-Mel140 may improve antitumor activity and transplant outcomes. Primary objectives was overall survival (OS) at 3 years. Secondary objectives were to assess the cumulative incidences of acute and chronic GVHD, relapse-free survival (RFS), relapse rate, and nonrelapse mortality (NRM). We retrospectively evaluated outcomes of patients receiving Flu-Mel140-TBI followed by HLA-matched donor allogeneic hematopoietic stem cell transplantation (alloSCT) using peripheral blood stem cells. Eighty-one patients (median age, 58 years) underwent alloSCT between January 2008 and December 2018. Thirty-one percent of patients had a prior transplant, 32% had high or very-high disease risk index, and the donor was unrelated in 70% of patients. Grade 3 to 4 regimen-related toxicities were mucositis (37%), cardiac toxicity (17%), and renal toxicity (10%). The cumulative incidence of grade III to IV acute GVHD at day +100 was 24.7% and chronic GVHD at 1 year was 51.3%. Median follow-up for survival was 6.1 years. At 3 years, OS was 39.81%, RFS was 31.47%, and relapse rate was 30.5%. One-year NRM was 29.9%. Patients undergoing first transplantation experienced improved OS compared with second or beyond (63.08% versus 42.31%, P = .02). After adjusting for disease subtypes, age (≤55 versus 55), comorbidity index (CI), number of transplant and GVHD prophylaxis, multivariable analysis did not demonstrate any survival difference among disease subtypes. High CI (≥3) was predictive of adverse OS and NRM, whereas older age (>55 years) was associated with high NRM. Our study shows that Flu-Mel140-TBI seems feasible and provides durable disease control. Addition of TBI did not appear to improve outcomes compared to previously published reports of Flu-Mel140. Considerable NRM could result from the inclusion of patients with older age and prior transplants.

Grade 3-4 cytokine release syndrome is associated with poor survival in haploidentical peripheral blood stem cell transplantation

The information on the impact of cytokine release syndrome (CRS) on haploidentical donor peripheral blood stem cell transplant (haploPBSCT) outcomes is limited. We retrospectively evaluated 98 patients who underwent haploPBSCT between June 2012 and June 2019 for the onset and severity of CRS per the ASTCT guidelines. The incidence of CRS was 93% (91/98). Outcomes were compared between grade 1-2 and 3-4 CRS. Eighty-one patients developed grade 1-2 CRS (89%) and 10 (11%) developed grade 3-4 CRS. Compared to grade 1-2 CRS, grade 3-4 CRS experienced adverse survival (73.7% vs. 30%, p<.001), inferior relapse-free survival (64.0% vs. 20%, p<.001), and higher non-relapse mortality (NRM) (16.4% vs. 60%, p<.001) at 1-year. Propensity score-based multivariable analyses revealed worse survival (HR 2.71, p=.04), and higher NRM (SHR 4.51, p=.006) with grade 3-4 CRS. Our study shows that grade 3-4 CRS was adversely associated with survival. Therefore, early identification and preventive strategies are warranted.

Comparison of myeloablative and reduced intensity conditioning unrelated donor allogeneic peripheral blood stem cell transplant outcomes for AML using thymoglobulin for GVHD prophylaxis

A head-to-head comparison of outcomes of unrelated donor allogeneic peripheral blood stem cell transplantation for AML between reduced intensity conditioning (RIC) and myeloablative conditioning (MAC) regimens using thymoglobulin for GVHD prophylaxis is limited. We evaluated outcomes of 122 AML patients who received either busulfan (Bu)/fludarabine (Flu)/low-dose total body irradiation (TBI) as RIC (n = 64, 52%) or Bu/Flu as MAC (n = 58, 48%), and thymoglobulin 4.5 mg/kg total dose between day - 3 to - 1 for GVHD prophylaxis. Grades III-IV acute GVHD (aGVHD) was lower with Bu/Flu/TBI compared with Bu/Flu (6.2% vs 26.1%, p = 0.009). At 1 year, Bu/Flu/TBI was associated with similar chronic GVHD (41.2% vs 44.8%, p = 0.75), OS (61.9% vs 56.9%, p = 0.69), relapse rate (29.9% vs 20.7%, p = 0.24), relapse-free survival (52.8% vs 50%, p = 0.80), non-relapse mortality (17.4% vs 29.3%, p = 0.41), and GVHD-free relapse-free survival (24.2% vs 27.5%, p = 0.80) compared with Bu/Flu. Multivariable analysis did not reveal any difference in outcomes between both regimens. In summary, thymoglobulin at 4.5 mg/kg did not have any adverse impact on survival when used with RIC regimen. Both Bu/Flu/TBI and Bu/Flu conditioning regimens yielded similar survival.

Midostaurin after allogeneic stem cell transplant in patients with FLT3-internal tandem duplication-positive acute myeloid leukemia

We evaluated standard-of-care (SOC) treatment with or without midostaurin to prevent relapse following allogeneic hematopoietic stem cell transplant (alloHSCT) in patients with acute myeloid leukemia (AML) harboring internal tandem duplication (ITD) in FLT3. Adults (aged 18–70 years) who received alloHSCT in first complete remission, had achieved hematologic recovery, and were transfusion independent were randomized to receive SOC with or without midostaurin (50 mg twice daily) continuously in twelve 4-week cycles. The primary endpoint was relapse-free survival (RFS) 18 months post-alloHSCT. Sixty patients were randomized (30/arm); 30 completed all 12 cycles (midostaurin + SOC, n = 16; SOC, n = 14). The estimated 18-month RFS (95% CI) was 89% (69–96%) in the midostaurin arm and 76% (54–88%) in the SOC arm (hazard ratio, 0.46 [95% CI, 0.12–1.86]; P = 0.27); estimated relapse rates were 11% and 24%, respectively. Inhibition of FLT3 phosphorylation to <70% of baseline (achieved by 50% of midostaurin-treated patients) was associated with improved RFS. The most common serious adverse events were diarrhea, nausea, and vomiting. Rates of graft-vs-host disease were similar between both arms (midostaurin + SOC, 70%; SOC, 73%). The addition of midostaurin maintenance therapy following alloHSCT may provide clinical benefit in some patients with FLT3-ITD AML. (ClinicalTrials.gov identifier: NCT01883362).

Comparison of myeloablative and reduced intensity conditioning regimens in haploidentical peripheral blood stem cell transplantation

Limited information is available on the impact of intensity of conditioning regimens in haploidentical peripheral blood stem cell transplant (haploPBSCT) with post-transplant cyclophosphamide (PTcy). We retrospectively compared outcomes of haplo-PBSCT between myeloablative (MAC) (n = 24) and reduced intensity conditioning (RIC) regimens (n = 65). Propensity score-based multivariable analyses were performed to adjust confounding effects of baseline characteristics between both groups. Eighty-nine patients underwent haplo-PBSCT between January 2012 and June 2019. For MAC and RIC, the cumulative incidences of grade III--IV acute GVHD were 4.2% and 3.1%, respectively (p = 0.92), and chronic GVHD were 18.9% and 36.5%, respectively (p = 0.08). Median follow-up for overall survival (OS) after MAC and RIC was 1.86 and 2.2 years, respectively. For MAC and RIC, one-year OS was 68.8% and 67.4%, respectively (p = 0.85); one-year relapse rate was 22.4% and 18.3%, respectively (p = 0.74); one-year relapse-free survival (RFS) was 56% and 59.7%, respectively (p = 0.87); and one-year non-relapse mortality (NRM) was 22% and 21.9%, respectively (p = 0.58). Using propensity score-based multivariable analyses, no difference in OS (HR 0.72, p = 0.51), relapse (SHR 0.63, p = 0.42), RFS (HR 0.74, p = 0.49) and NRM (SHR 1.11, p = 0.87) was noted between RIC and MAC. Our study shows no difference in outcomes between MAC and RIC regimens in haplo-PBSCT.

G-CSF use post peripheral blood stem cell transplant is associated with faster neutrophil engraftment, shorter hospital stay and increased incidence of chronic GVHD

The use of G-CSF post allogeneic transplant has become a common practice to accelerate neutrophil engraftment. There is some controversy in its use. To further evaluate the effectiveness, we compared outcomes in patients who underwent PBSCT, either with or without the planned use of G-CSF post SCT. Among consecutive 162 patients from October 2012 to October 2014, 65 patients received G-CSF post-PBSCT, and 97 did not. More patients in G-CSF group received MAC (78% vs. 55%). Patients who received G-CSF had earlier neutrophil engraftment (median days 11 vs. 14) and shorter post-transplant hospital stay (median days 16 vs. 20, p = 0.001). G-CSF use was associated with a higher rate of extensive chronic GVHD (44.3% vs.61.5%, p = 0.027). G-CSF cost the equivalent of 0.25 hospital days but shortened the initial transplant admission by 4 days. Early cost-benefit may be later offset by the economic burden of chronic GVHD and associated complications.

Standard-of-Care Axicabtagene Ciloleucel for Relapsed or Refractory Large B-Cell Lymphoma: Results From the US Lymphoma CAR T Consortium

PURPOSE

Axicabtagene ciloleucel (axi-cel) is an autologous CD19-directed chimeric antigen receptor (CAR) T-cell therapy approved for relapsed/refractory large B-cell lymphoma (LBCL) on the basis of the single-arm phase II ZUMA-1 trial, which showed best overall and complete response rates in infused patients of 83% and 58%, respectively. We report clinical outcomes with axi-cel in the standard-of-care (SOC) setting for the approved indication.

PATIENTS AND METHODS

Data were collected retrospectively from all patients with relapsed/refractory LBCL who underwent leukapheresis as of September 30, 2018, at 17 US institutions with the intent to receive SOC axi-cel. Toxicities were graded and managed according to each institution's guidelines. Responses were assessed as per Lugano 2014 classification.

RESULTS

Of 298 patients who underwent leukapheresis, 275 (92%) received axi-cel therapy. Compared with the registrational ZUMA-1 trial, 129 patients (43%) in this SOC study would not have met ZUMA-1 eligibility criteria because of comorbidities at the time of leukapheresis. Among the axi-cel-treated patients, grade ≥ 3 cytokine release syndrome and neurotoxicity occurred in 7% and 31%, respectively. Nonrelapse mortality was 4.4%. Best overall and complete response rates in infused patients were 82% (95% CI, 77% to 86%) and 64% (95% CI, 58% to 69%), respectively. At a median follow-up of 12.9 months from the time of CAR T-cell infusion, median progression-free survival was 8.3 months (95% CI, 6.0 to15.1 months), and median overall survival was not reached. Patients with poor Eastern Cooperative Oncology Group performance status of 2-4 and elevated lactate dehydrogenase had shorter progression-free and overall survival on univariable and multivariable analysis.

CONCLUSION

The safety and efficacy of axi-cel in the SOC setting in patients with relapsed/refractory LBCL was comparable to the registrational ZUMA-1 trial.

Clinical and immune responses to anti-CD3 x anti-EGFR bispecific antibody armed activated T cells (EGFR BATs) in pancreatic cancer patients

Purpose

This was a phase I/II adoptive T cell trial in 7 locally advanced and metastatic pancreatic cancer patients using 3–8 infusions of anti-CD3 x anti-EGFR bispecific antibody armed activated T cells (BATs) to determine safety, the maximum tolerated dose (MTD), immune responses, time to progression (TTP), and overall survival (OS). Study Design: T cells obtained by apheresis were expanded and armed with EGFRBi, cryopreserved for infusions. In a phase I dose escalation, five patients received three weekly infusions of 10–40 × 10⁹ BATs/infusion followed by a booster infusion 3 months later, and 2 patients received 8 infusions twice weekly for 4 weeks in a phase II. The trials were registered at http://www.clinicaltrials.gov, NCT01420874 and NCT02620865. Results: There were no dose-limiting toxicities (DLTs), and the targeted dose of 80 × 10⁹ BATs was met. The median TTP is 7 months, and the median OS is 31 months. Two patients had stable disease for 6.5 and 25+ months, and two patients developed complete responses (CRs) after restarting chemotherapy. Infusions of BATs induced anti-pancreatic cancer cytotoxicity, innate immune responses, cytokine responses (IL-12, IP-10), and shifts in CD4 and CD8 Vβ repertoire with enhanced cytoplasmic IFN-γ staining in the Vβ repertoire of the CD8 subset that suggest specific clonal TCR responses. Conclusions: Infusions of BATs are safe, induce endogenous adaptive anti-tumor responses, and may have a potential to improve overall survival.

Grade III-IV cytokine release syndrome is associated with inferior survival in patients undergoing haploidentical donor stem cell transplants

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Background: Haploidentical transplant (HIDT) with post-transplant cyclophosphamide (pCY) is being increasingly used because of the universal availability of donor and rapid graft acquisition time. Cytokine release syndrome (CRS) is one of the commonly occurring complications in this population. The information on the impact of CRS on the post-HIDT outcomes is limited. Methods: We retrospectively evaluated 91 patients who underwent HIDT between June 2012 and June 2019 for the onset and severity of CRS. CRS was graded per ASTCT guidelines. The primary objective was to compare RFS (relapse-free survival), NRM (non-relapse mortality), OS (overall survival) and GVHD in patients with no CRS, CRS grade 1-2 and 3-4. Results: All received peripheral blood stem cells and pCY/tacrolimus/mycophenolate as GVHD prophylaxis. Fifty-six (62%) received reduced intensity and 35 (38%) received full intensity conditioning regimen. Ten (10.9%) had no CRS, 74 (81.3%) developed grade 1-2 CRS and seven (7.7%) experienced grade 3-4 CRS. Median time to onset of CRS was one day post-transplant. The most common symptoms were fever (87%), fatigue (30%), nausea/vomiting (24%), rigors (24%), diarrhea (20%) and rash (11%). Fifteen (20%) with grade 1-2 and six (85%) with grade 3-4 CRS received tocilizumab. Day +100 cumulative incidence of grade III-IV acute GVHD for no CRS, grade 1-2 and grade 3-4 CRS was 0%, 2.7%, and 14.3%, respectively (P = 0.36). One-year cumulative incidence of chronic GVHD for no CRS, grade 1-2 and grade 3-4 CRS was 30%, 31.9% and 14.3%, respectively (P = 0.70). One-year NRM for no CRS, grade 1-2 and grade 3-4 CRS was 30%, 16.5%, and 57.1%, respectively (P = 0.002). One-year RFS for no CRS, grade 1-2 and grade 3-4 CRS was 48%, 63.4% and 28.6%, respectively (p = 0.03). OS at 1-year for no CRS, grade 1-2 and grade 3-4 CRS was 60%, 73.9%, and 28.6%, respectively (P = 0.008). Multivariable analysis revealed that grade 3-4 CRS was associated with significantly higher NRM (HR 5.54, P = 0.002), worse RFS (HR 3.41, P = 0.011) and worse OS (HR 4.91, P = 0.001). Conditioning regimen, degree of HLA match and disease risk index did not affect post-transplant outcomes and were not predictors for developing CRS. Conclusions: Our study showed that grade 3-4 CRS was associated with inferior post-transplant outcomes. However, no impact on acute or chronic GVHD was noted. Therefore, early recognition and prompt management of CRS may help improve outcomes.

Very long term follow-up of high dose chemotherapy followed by autologous stem cell transplantation in high risk locally advanced triple negative breast cancer

e13094

Background: The role of High Dose Chemotherapy (HDC) with Autologous Stem Cell Transplantation (ASCT) in treatment of high risk locally advanced breast cancer remains unclear. This modality stopped being used for breast cancer treatment when trials in early 2000s reported Disease Free Survival (DFS) benefit but no Overall survival (OS) benefit. However, subgroup analyses of these studies reported OS benefit in young and Triple Negative Breast Cancer (TNBC). We report very long-term outcomes of high risk locally advanced TNBC treated with HDC-ASCT at our institution between 1995 and 2001. Methods: We reviewed our BMT database for women with stage IIB or III TNBC treated with HDC-ASCT. We excluded women with hormone positive, Her2/Neu positive/Unknown and metastatic disease prior to transplant per updated AJCC 7th edition. The majority of patients underwent surgery followed by adjuvant Anthracycline and Taxane based induction chemotherapy followed by HDC-ASCT for consolidation. The HDC regimen consisted of Carmustine 600 mg/m2, Cyclophosphamide 5.6gm/ m2 and Cisplatin 165mg/ m2 (STAMP 1 regimen). Four patients received induction regimen as neoadjuvant and HDC-ASCT as adjuvant treatment per the same protocol. All patients received loco-regional radiation after ASCT. Results: 29 patients had locally advanced TNBC treated with HDC-ASCT. Median age at diagnosis was 43 years (IQR 40-51). 28 had at least 4 positive lymph nodes. Median time from diagnosis to ASCT was 5 months. Median overall survival was 17 years (95% CI, 3-19 years), and median DFS was 14 years (95% CI, 1-19). There was no treatment related mortality (TRM) at 30- and 100-days post ASCT. 12 patients (41%) were alive at median of 16 years (95% CI, 12-19) post ASCT. Conclusions: This single institution study of locally advanced high risk TNBC patients who received HDC-ASCT as part of treatment demonstrates a high long term OS exceeded historical controls. This supports a potential role for HDC-ASCT in this cohort of high risk TNBC. Considering the low TRM associated with this approach, prospective evaluation of this strategy is warranted.

Toxicities after high dose post-transplant cyclophosphamide in haploidentical donor transplants: Risk factors and impact on survival

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Background: Post-transplant cyclophosphamide (pCY) when given at 50mg/kg on day +3 and +4 in haploidentical donor transplants (HIDT) leads to considerable morbidity. Information on its toxicity and impact on outcomes is limited. Methods: We analyzed 91 patients (pt) undergoing HIDT with pCY to estimate incidence and risk factors of mucositis, hemorrhagic cystitis, renal and cardiac toxicities during the first 6 months after transplant and its impact on overall survival (OS). We compared these complications with 91 pt who were matched for age, disease, disease status at transplant, conditioning regimen and received 8/8 HLA-matched transplants without pCY (non-pCY cohort). Results: Fourteen pt (15%) in non-pCY and 28 (31%) in pCY experienced hypoxia requiring oxygen (p = 0.03). Ten pt (11%) in non-pCY and 21 (23%) in pCY developed clinically significant hypotension (p = 0.05). Day +100 cumulative incidence rate (CIR) of mucositis was 59.3% for non-pCY and 84.6% for pCY (p < 0.001). Seven pt (13%) in non-pCY cohort and 39 (51%) in pCY developed grade 3-4 mucositis (p < 0.001). Two pt (2%) in non-pCY and 22 (24%) in pCY developed gross hematuria (p = 0.05). Day +180 CIR of hemorrhagic cystitis was 13.2% for non-pCY and 29.7% for pCY (p = 0.005). Hemorrhagic cystitis did not have an adverse impact on non-relapse mortality (NRM) and OS. Day +180 CIR of renal toxicities was 17.6% for non-pCY and 28.6% for pCY (p = 0.10). The CIR of cardiac toxicities at day +180 was 9.9% for non-pCY and 14.3% for pCY (p = 0.34). Congestive heart failure (59%) and atrial fibrillation (36%) were the most common cardio-toxicities. One-year NRM was 38.5% in pt developing cardio-toxicity in the pCY cohort compared to no cardio-toxicity (15.3% in non-pCY and 18.3% in pCY, p = 0.004). OS was inferior in pt with cardio-toxicity in non-pCY (HR 5.49, p < 0.001) and pCY (HR 2.3, p = 0.03) compared to pt without cardio-toxicity. In multivariable analysis, pCY was associated with an increased risk of mucositis (HR 1.48, p = 0.03), and hemorrhagic cystitis (HR 2.67, p = 0.004). The number of infused CD34 cells was associated an increased risk of cardiac toxicity (HR 1.13, p = 0.005). pCY was not associated with higher cardiac complications, and no impact of the number of infused CD34 cells, conditioning regimen and prior transplant was observed on hemorrhagic cystitis and mucositis. Conclusions: pCY was associated with significant morbidity compared to HLA-matched non-pCY cohort. Although cardio-toxicities were similar between both groups, it was associated with worse survival.

Lenalidomide maintenance after second autologous stem cell transplant improves overall survival in multiple myeloma

Maintenance therapy after first autologous transplant (autoSCT) improves progression-free survival (PFS) and overall survival (OS) in multiple myeloma (MM). However, efficacy of maintenance therapy after second autoSCT is unknown. We retrospectively evaluated outcomes of 111 adult MM patients who underwent second autoSCT between January 2000 and December 2018. Lenalidomide up to 15 mg daily or subcutaneous bortezomib 1.3 mg/m² every 2 weeks was considered maintenance therapy. Outcomes were compared among three groups: no-maintenance (n = 73), lenalidomide (n = 23), and bortezomib maintenance (n = 15). At a median follow-up of 58 months from second autoSCT for survival, 3-year PFS and OS for no-maintenance, lenalidomide, and bortezomib maintenance were 11.2%, 29.9%, and 0%, respectively; and 58.5%, 83.3%, and 67.5% respectively. Lenalidomide maintenance was associated with improved PFS (HR 0.46, p = 0.009) and OS (HR 0.25, p = 0.009) compared to no-maintenance. Lenalidomide maintenance therapy after second autoSCT appears to prolong PFS and OS.