ALBERT

Description: Abstract 2800 Background: Pralatrexate (FOLOTYN®) is an antifolate designed for preferential tumor uptake and accumulation. Pralatrexate was granted accelerated approval by the US Food and Drug Administration at a dose of 30 mg/m2 weekly for 6/7 weeks for relapsed or refractory peripheral T-cell lymphoma. Given that cutaneous T-cell lymphoma (CTCL) is often an indolent disease treated in a maintenance fashion, the goal of this trial was to identify a dose with clinical activity and minimal toxicity to allow continuous or maintenance treatment. In the present study, designated PDX-010, the initial dose of pralatrexate for relapsed or refractory CTCL was based on data showing that 30 mg/m2 demonstrated activity in patients with aggressive lymphoma. A dose de-escalation strategy was used in PDX-010 to identify an optimal dose for CTCL. Methods: Eligibility included CTCL histology of mycosis fungoides, Sézary syndrome, or primary cutaneous anaplastic large-cell lymphoma, with disease progression after at least 1 prior systemic therapy, and written informed consent. The starting dose and schedule was 30 mg/m2 of pralatrexate by intravenous (IV) push weekly for 3/4 weeks. If toxicity as defined per the protocol was observed, subsequent cohorts received reduced doses (20, 15, 10 mg/m2) and/or schedules (weekly for 3/4 or 2/3 weeks). All patients received supplementation with vitamin B12 1 mg intramuscularly every 8 to10 weeks, and folic acid 1 mg orally once daily (QD). Response was evaluated by the modified severity weighted adjustment tool (mSWAT) every 2 cycles for 6 months, and then every 4 cycles. For patients with lymph node involvement, scans were completed at baseline and upon clinical response or end of treatment, whichever occurred first. Results: Fifty-four patients were treated across 2 stages of this study. In the dose-finding phase, 31 patients were sequentially enrolled into 6 cohorts and treated at varying doses and schedules. The optimal dose and schedule, as defined in the protocol, was identified as 15 mg/m2 weekly for 3/4 weeks, based on the tolerability and efficacy (overall response rate [ORR] of 50%) observed in the initial 6 patients in that cohort. Among the 31 patients in the dose-finding stage, the ORR for patients treated at a dose intensity ≥15 mg/m2 weekly for 3/4 weeks was 61% (11/18), and the ORR for those patients treated in lower-dose cohorts was 8% (1/13). The second stage of the study included 23 additional patients treated at 15 mg/m2 weekly for 3/4 weeks, for a total of n = 29 patients treated at this optimal dose. Among these 29 patients, the median number of prior systemic therapies was 4.5 (range 1 to 11), and patients received pralatrexate for a median of 4 cycles (range 1 to 23). Patients enrolled in this cohort could be dose-escalated at investigator discretion if there was an absence of toxicity and a response 〈 CR. At this time 53/54 patients treated in this study are evaluable for efficacy, including 28/29 patients treated at 15 mg/m2 for 3/4 weeks. At the optimal dose, the ORR was 43% (12/28) and 50% (20/40) in patients treated at a dose intensity ≥15 mg/m2 weekly for 3/4 weeks. At the optimal dose/schedule, grade 1–2 adverse events (AEs) occurring in 〉10% were fatigue (34%), mucositis (28%), nausea (24%), edema (24%), epistaxis (21%), pyrexia (17%), constipation (14%), and vomiting (14%). The only grade 3 AE in 〉10% was mucositis (17%). Hematologic toxicities were limited to grade 3 neutropenia (3%), grade 1–2 anemia (14%), grade 3 anemia (3%), grade 1–2 thrombocytopenia (7%), grade 3 thrombocytopenia (3%), grade 1–2 leukopenia (3%), and grade 4 leukopenia (3%). No grade 4 nonhematological toxicities were observed. Conclusions: Pralatrexate shows high activity with acceptable toxicity in patients with relapsed or refractory CTCL at the identified optimal dose and schedule of 15 mg/m2 weekly for 3/4 weeks. The lack of significant hematologic toxicity or cumulative toxicity seen in this study suggests that pralatrexate should be further evaluated as continuous or maintenance therapy for patients with CTCL. Final efficacy and tolerability data will be reported. Disclosures: Horwitz: Allos Therapeutics, Inc.: Consultancy, Research Funding. Foss:Allos Therapeutics, Inc.: Consultancy, Speaker. Zain:Allos Therapeutics, Inc. : Speakers Bureau. Lechowicz:Allos Therapeutics, Inc.: Consultancy; Celgene Corporation : Consultancy. Shustov:Allos Therapeutics, Inc.: Honoraria, Research Funding. Koutsoukos:Allos Therapeutics, Inc.: Employment. Fruchtman:Allos Therapeutics, Inc.: Employment. O'Connor:Allos Therapeutics, Inc.: Research Funding. Duvic:Allos Therapeutics, Inc.: Research Funding.

Description: Introduction Tenalisib (RP6530) is a next generation, oral, selective, PI3Kδ/g inhibitor with nanomolar inhibitory potency. Besides its apoptotic and anti-proliferative activity, Tenalisib modulates the tumor microenvironment resulting in reprogramming of tumor associated-macrophages (TAMs) from a protumor M2 phenotype to an antitumor M1 phenotype and a marked reduction of angiogenesis in pre-clinical models. Tenalisib has demonstrated activity in patients with relapsed/refractory lymphoid malignancies (Carmelo, ASH 2016 and Oki, ASCO 2018). Since there are concerns over long-term safety of PI3K δ or PI3K dual δ/g inhibitors with respect to immune-mediated toxicities (e.g. transaminitis, colitis and pneumonitis), cytopenias, and infections, a pooled safety analysis across two Phase I studies in patients treated with Tenalisib was performed. Methods Safety data was pooled from two Phase I Tenalisib monotherapy trials (NCT02017613 and NCT02567656) with similar key eligibility criteria. Patients had R/R lymphoid malignancies with ≥1 prior therapy. Responses were evaluated in lymphoid malignancies using IWG criteria (Cheson et al., 2007) and in CTCL using the modified Severity Weighted Assessment Tool (mSWAT). Adverse events were graded according to CTCAE v4.03. Results A total of 93 patients were included in the analysis. Among these patients, 34% were PTCL, 32% CTCL, 16% HL, 6% DLBCL and 12% were other lymphomas. Patients received a median of 5 prior therapies. 53 % of patients received Tenalisib for ≤ 3 months, 21% for 3-6 months and 26% for 〉 6 months. The overall incidence of related AEs and ≥G3 AEs were 58% and 29% respectively (Table 1). Very few AEs were seen with exposures 〉6 months and mainly included single cases of diarrhea, anemia, edema, and abdominal pain. There were no incidences of late onset toxicities such as colitis and pneumonitis and most of the AEs happened during the initial three months of therapy. No treatment discontinuations due to AE's were seen in patients exposed to 〉 6 months of treatment. Efficacy response assessments of the 66 evaluable patients demonstrated an ORR of 45% in TCL (44% in PTCL (8/18, 3 CR, 4 PR) & 45% in CTCL (9/20, 9 PR)), 29% (4/14; 1CR; 3PR) in HL, and 13% (1/6; 1CR) in DLBCL. Conclusion In this pooled safety analysis with long term follow-up, Tenalisib exhibited an improved safety profile when compared to other investigational/marketed PI3K inhibitors. The incidence of transaminitis was low and occurred within the first two to three cycles of therapy. In particular, there were no occurrences of pneumonitis or colitis in patients that had been on treatment for 〉 3 months and beyond. Incidence of neutropenia/thrombocytopenia and infections was limited. Tenalisib can therefore be safely combined with a diverse array of other agents active in lymphoid malignancies. Tenalisib is currently being studied in combination with Pembrolizumab and Romidepsin and as a monotherapy in a Phase II trial in indolent NHL. Disclosures Haverkos: Viracta Therapeutics: Membership on an entity's Board of Directors or advisory committees. Ramchandren:Pharmacyclics LLC an AbbVie Company: Consultancy, Research Funding; Seattle Genetics: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy; Merck: Research Funding; Janssen: Consultancy, Research Funding. Devata:Affimed: Research Funding. Routhu:Rhizen Pharmaceuticals SA: Employment. Barde:Rhizen Pharmaceuticals SA: Employment. Nair:Rhizen Pharmaceuticals SA: Employment. Carlo-Stella:Boehringher Ingelheim Italia: Consultancy; Sanofi: Consultancy; MSD Italia: Speakers Bureau; Rhizen Pharmaceuticals: Research Funding; AstraZeneca: Speakers Bureau; ADC Therapeutics: Research Funding, Speakers Bureau; Janssen: Speakers Bureau; Genenta Science: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau; Amgen: Speakers Bureau.

Description: Introduction: Patients (pts) with relapsed/refractory PMBCL (rrPMBCL) are typically treated like those with diffuse large B cell lymphoma (DLBCL), often with limited effective treatment options and poor outcomes. Unlike DLBCL and similar to classical Hodgkin lymphoma, PMBCL has frequent genetic abnormalities leading to over-expression of the programmed death (PD)-1 ligands, PD-L1 and PD-L2. This suggests that rrPMBCL should be sensitive to PD-1 blockade. In the phase 1b KEYNOTE (KN)-013 study (NCT01953692), pembrolizumab was associated with frequent and durable responses (Zinzani, Blood 2017) in pts with rrPMBCL. The international phase 2 KN170 (NCT02576990) study was conducted to extend these findings and evaluate correlative biomarkers of response. Here, we present updated results of all pts in KN013 (n=21) and the first full analysis of pts in KN170 (n=53). Methods: KN013 enrolled pts with rrPMBCL who had failed, were ineligible for, or refused autologous stem cell transplant (ASCT). KN170 enrolled pts with rrPMBCL who had relapsed after or were ineligible for ASCT with ≥2 lines of prior therapy. In KN013, the initial 10 pts received pembrolizumab 10 mg/kg Q2W; the remaining 11 patients and all patients on KN170 received pembrolizumab 200 mg Q3W for up to 2 years. Archival or fresh tumor tissue obtained before pembrolizumab initiation was used for correlative studies. Tumor response was assessed with PET/CT scans by IWG 2007 criteria. The primary endpoint of KN170 was objective response rate (ORR) by blinded independent central review (BICR). Secondary endpoints included duration of response (DOR), progression-free survival (PFS), overall survival (OS), and safety/tolerability. Exploratory endpoints included response by Lugano 2014 criteria and biomarker analyses. Data cutoff dates for this analysis were Apr 4, 2018 for KN013 and April 13, 2018 for KN170. Results: KN013 enrolled 21 pts with a median of 3 prior lines of therapy, of whom 13 (62%) were ASCT-ineligible. KN170 enrolled 53 pts also with a median of 3 prior lines, of whom 39 (74%) were ASCT-ineligible due to chemorefractoriness. In KN013, ORR was 48% (10/21; 95% CI, 26-70), with a CR rate of 33% (7/21). In KN170, ORR was 45% (24/53; 95%CI, 32-60), with a CR rate of 13% (7/53; 11/53 [21% by Lugano criteria]). In KN013, after a median follow-up duration of 29.1 mo (range, 0.6-49.6), median DOR was not reached (range, 1.9+ to 39.8+ mo) (Panel A). 2 patients in KN013 in CR at 2 years remained in CR after a further 12 and 18 mo of follow-up off therapy. After a median follow-up of 12.5 mo for KN170 (range, 0.1-25.6), median DOR was not reached (range, 1.1+ to 22.0+ mo) (Panel A). At data cutoff, no patient who achieved a CR on KN170 had relapsed. In KN013, median PFS was 10.4 mo (95%CI, 3.4 to not reached) with 12-mo PFS rate of 47%; median OS was 31.4 mo with 12-mo OS rate of 65% (Panel B). In KN170, median PFS was 5.5 mo (95%CI, 2.8-12.1) with 12-mo PFS rate of 38%; median OS was not reached (95% CI, 7.3 to not reached) with 12-mo OS rate of 58% (Panel B). In KN013, no new safety signals were observed compared with prior analyses. In KN170, 30 (57%) pts had a treatment-related AE (TRAE). Common (≥5%) TRAEs included neutropenia (19%), hypothyroidism and asthenia (8% each), and pyrexia (6%). 12 (23%) pts had a grade 3-4 TRAE, including 5 (9%) with grade 3 and 2 (4%) with grade 4 neutropenia. Six (11%) pts had an immune-mediated AE including 1 (2%) with grade 4 pneumonitis. There were no treatment-related deaths. Conclusion: Together with the longer follow-up results of KN013, KN170, the largest prospective clinical trial in rrPMBCL, establishes the robust antitumor activity of pembrolizumab in this disease, with exceptionally durable responses and survival in responding patients. These results provided the basis for the FDA accelerated approval of pembrolizumab in patients with rrPMBCL. Disclosures Armand: Otsuka: Research Funding; Adaptive: Research Funding; Merck: Consultancy, Research Funding; Affimed: Consultancy, Research Funding; Pfizer: Consultancy; Infinity: Consultancy; Bristol-Myers Squibb: Consultancy, Research Funding; Roche: Research Funding; Tensha: Research Funding. Rodig:Merck & Co., Inc.: Research Funding; Affimed Inc.: Research Funding; KITE Pharma: Research Funding; Bristol-Meyers-Squibb: Research Funding. Özcan:Jazz: Other: Travel support; Bayer: Research Funding; BMS: Honoraria; MSD: Other: travel support, Research Funding; Janssen: Other: Travel Support, Research Funding; Jazz: Other; Celgene: Other: Travel support, Research Funding; Roche: Honoraria, Research Funding; Archigen: Research Funding; Novartis: Research Funding; MSD: Research Funding; Abbvie: Other: Travel payment; Takeda: Honoraria, Other: Travel payment, Research Funding. Fogliatto:Novartis: Consultancy; Roche: Consultancy, Speakers Bureau; Janssen: Honoraria, Research Funding. Walewski:Roche, Celegene, Takeda, Janssen-Cilag, and Servier: Membership on an entity's Board of Directors or advisory committees; Roche, Celgene, Takeda, Janssen-Cilag, and Servier: Honoraria; Roche, GSK/Novartis, Takeda, and Janssen-Cilag: Research Funding. Gulbas:Pfizer: Other: Travel expenses; Roche and Janssen: Honoraria; Gilead: Research Funding; Roche: Membership on an entity's Board of Directors or advisory committees. Ribrag:Incyte Corporation: Consultancy; MSD: Honoraria; NanoString Technologies: Consultancy, Honoraria; BMS: Consultancy, Honoraria, Other: travel; Gilead: Consultancy, Honoraria; Roche: Honoraria, Other: travel; Infinity: Consultancy, Honoraria; epizyme: Consultancy, Honoraria; Amgen: Research Funding; pharmamar: Other: travel; Servier: Consultancy, Honoraria; argenX: Research Funding. Christian:Immunomedics: Research Funding; Bristol-Myers Squibb: Research Funding; Merck: Research Funding; Acerta: Research Funding; Celgene: Research Funding; Seattle Genetics: Research Funding; Genentech: Membership on an entity's Board of Directors or advisory committees, Research Funding. Perini:Janssen and Abbvie: Membership on an entity's Board of Directors or advisory committees; Janssen and Takeda: Speakers Bureau; Janssen and Takeda: Other: Travel expenses. Salles:Merck: Honoraria; Novartis: Consultancy, Honoraria; Roche: Honoraria, Research Funding; Celgene: Honoraria, Research Funding; AbbVie: Honoraria; Acerta: Honoraria; Takeda: Honoraria; Pfizer: Honoraria; Morphosys: Honoraria; Servier: Honoraria; Amgen: Honoraria; Epizyme: Honoraria; Gilead: Honoraria; Janssen: Honoraria. Svoboda:Pharmacyclics: Consultancy, Research Funding; Bristol-Myers Squibb: Consultancy, Research Funding; Kyowa: Consultancy; Regeneron: Research Funding; TG Therapeutics: Research Funding; KITE: Consultancy; Merck: Research Funding; Seattle Genetics: Consultancy, Research Funding. Chatterjee:Merck & Co., Inc.: Employment. Orlowski:Merck & Co., Inc.: Employment. Balakumaran:Amgen: Equity Ownership; Merck & Co., Inc.: Employment, Equity Ownership. Shipp:Bayer: Research Funding; Bristol-Myers Squibb: Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; AstraZeneca: Honoraria; Merck: Research Funding. Zinzani:PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; BMS: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Janssen: Honoraria, Speakers Bureau; Roche: Honoraria, Membership on an entity's Board of Directors or advisory committees; Astra Zeneca: Speakers Bureau; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; SERVIER: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Celltrion: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Bayer: Membership on an entity's Board of Directors or advisory committees; Merck: Honoraria, Membership on an entity's Board of Directors or advisory committees; TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; TG Pharmaceuticals: Honoraria, Membership on an entity's Board of Directors or advisory committees; Bayer: Membership on an entity's Board of Directors or advisory committees; MSD: Honoraria, Speakers Bureau; PFIZER: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Membership on an entity's Board of Directors or advisory committees; Gilead: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Verastem: Honoraria, Membership on an entity's Board of Directors or advisory committees, Speakers Bureau.

Description: The majority of patients (pts) with PTCL present with advanced stage with high-intermediate or high-risk IPI and their prognosis are poor with current standard induction chemotherapy. HDT followed by ASCT has been shown to be effective therapy for relapsed and refractory PTCL, although the outcomes of transplant varied depending upon the histologic subtype, disease status and IPI at transplant. Given the poor outcome with current treatment approach, HDT and ASCT as consolidative therapy during first remission are being investigated in pts with PTCL. We performed retrospective analysis of all pts with T-cell, NK cell and null cell lymphomas who underwent HDT and ASCT between 2/1991 to 6/2005. We analyze the outcome based on disease status at transplant and the subset of PTCL. There were 57 pts (35 male, 22 female) with a median age of 45 years (range 5–68). Histology included 6 (10.5%) angioimmunoblastic T-cell lymphoma (AILD), 26(46%) Anaplastic large cell lymphoma (ALCL), 22 (39%) PTCL, unspecified (NOS), 1 panniculitis like T-cell, 1 NK-T, and 1 adult T-cell lymphoma. Twelve (21%) were transplanted during first remission; 11 were high intermediate-high risk IPI, and 1 for histology NK-T. Twenty-eight (49%) were transplanted during relapse or ≥second remission and 17 (30% ) induction failure or primary refractory disease. Twenty-one (37%) had advanced stage III-IV at transplant. The median number of chemotherapy regimens was 2 (range 1–5). For ALCL subtype, 9 were anaplastic lymphoma kinase (ALK) positive, 9 ALK negative, 8 unknown. Results: At a median follow-up of 22 months (range 0.5–179), 29 are alive in remission, 25 relapsed and 3 died from transplant related mortality. One patient developed therapy induced myelodysplasia at two years post ASCT and is alive in remission after allogeneic stem cell transplant. The 2 years overall survival (OS) and disease-free survival (DFS) for the whole group were 53% (95% CI 46–60), and 45% (95% CI 39–50), respectively. The OS and DFS were significantly better for pts. who were transplanted in first complete remission (Figure1). The 2-year OS and DFS were both 83% (95% CI 55–94) for pts. transplanted in first remission compared to 45% (95% CI 38–52%, p=0.03) and 35% (95% CI 30–40, p= 0.006), respectively for those transplanted beyond first remission. Univariate models showed that the risk of death and/or relapse was significantly less among the pts. transplanted in first complete remission (OS, DFS and time to relapse: p 〈 0.05). When compared the outcome among the 3 subtypes, AILD, ALCL and PTCL NOS, there were no significant differences in survival or relapse among the 3 groups. Conclusion: our results suggest that HDT and ASCT can improve prognosis and survival of pts. with PTCL. The outcome of ASCT is best when performed during first complete remission. The role of HDT and ASCT during first remission should be further investigated in larger multi-center studies. In contrast to other reports, the prognosis of pts. with ALCL is similar to other PTCLs. Disease-Free Survival: ASCT for PTCL
 Startified by Disease Status: 1CR (n=12) vs. 〉 1CR (n=45) Disease-Free Survival: ASCT for PTCL
 Startified by Disease Status: 1CR (n=12) vs. 〉 1CR (n=45)

Description: Pralatrexate is a novel antifolate, which shows increased antitumor activity in human tumor xenograft studies in mice compared with methotrexate. We investigated the effects of pralatrexate in a patient with adult T-cell lymphoma/leukemia with significant skin involvement. Atypical lymphocytes in epidermal Pautrier microabscesses were positive for HTLV-1. After the patient presented with leukemic conversion and with worsening of an erythematous generalized papular rash, he received one dose of pralatrexate. Within one week, his skin developed innumerable small erosions limited to the areas of the papular rash, sparing unaffected skin. Here we present in vivo evidence that pralatrexate-induced erosions in skin affected by adult T-cell lymphoma/leukemia are a manifestation of apoptosis of tumor cells infiltrating the epidermis and are not the result of cytotoxicity by pralatrexate on keratinocytes. This distinction is critical and may profoundly influence the clinical decision to continue pralatrexate treatment. Pralatrexate-induced skin erosions may indicate response to treatment.

Description: Current CGVHD prognostic and staging systems are still undergoing development and have identified plt count; CGVHD types progressive(P), quiescent(Q), de novo(DN); KPS, and GI involvement as significant risk factors affecting outcome. A simple reproducible staging system such as used for AGVHD to apply in clinical trials is still lacking. We evaluated whether the PSE dose required to control CGVHD at 3 months from diagnosis would have a prognostic effect on survival and in and of itself serve as a criteria for secondary intervention or investigational therapy. We hypothesized that by 3 months from start of treatment patients would be on the lowest dose dictated by medical necessity rather than by physician driven dose preference. A retrospective analysis of charts from 109 patients diagnosed with CGVHD between 6/2000 and 6/2003 was done. Data collected included age, donor type(mud/sib), plt count, CGVHD type(P/Q/DN), KPS, GI involvement. Outcome analysis included survival and cause of death. PSE dose was calculated in mg/kg at 3 months from first diagnosis of CGVHD. With a median follow up of 47.2 months(range 6.6–67.2) relapse censored survival of patients on a 3 month PSE dose of more than .3 mg/kg was 53% compared to all lower doses 86%(P.03). In a univariate analysis only PSE dose (P .05) and KPS (P

Description: Systemic treatment for cutaneous T-cell lymphoma (CTCL) involves the use of less aggressive, well-tolerated therapies. Pralatrexate is a novel antifolate with high affinity for reduced folate carrier-1. A dose de-escalation strategy identified recommended pralatrexate dosing for patients with CTCL that demonstrated high activity, good rates of disease control, and an acceptable toxicity profile for continuous long-term dosing. Eligibility included mycosis fungoides, Sézary syndrome, or primary cutaneous anaplastic large cell lymphoma, with disease progression after ≥ 1 prior systemic therapy. The starting dose and schedule was 30 mg/m2/wk intravenously for 3 of 4 (3/4) weeks. Subsequent starting doses were 20, 15, and 10 mg/m2/wk for 3/4 or 2 of 3 (2/3) weeks. Response was evaluated by the modified severity-weighted adjustment tool. Fifty-four patients were treated. The recommended regimen was identified as 15 mg/m2/wk for 3/4 weeks and was explored in the expansion cohort. In 29 patients treated overall with the recommended dosing regimen, the median number of prior systemic therapies was 4. Pralatrexate was administered for a median of 4 cycles; response rate was 45%. The most common grade 3 adverse event (AE) was mucositis (17%); the only grade 4 AE was leukopenia (3%). Pralatrexate 15 mg/m2/wk for 3/4 weeks shows high activity with acceptable toxicity in patients with relapsed/refractory CTCL.

Description: Abstract 4882 Background: The most common therapy for first-line treatment of peripheral T-cell lymphoma (PTCL) is cyclophosphamide/doxorubicin/vincristine/prednisone (CHOP). However, most patients progress within 6 to 12 months and there is no standard of care for second-line treatment. Despite a paucity of data in PTCL, B-cell lymphoma salvage regimens are regularly employed as a second-line treatment for PTCL. Pralatrexate was granted accelerated approval in the United States for the treatment of patients with relapsed or refractory PTCL, based on the results of the pivotal study, PROPEL (Pralatrexate in Patients with Relapsed Or Refractory Peripheral T-cell Lymphoma). All patients in PROPEL had received at least 1 prior therapy for PTCL, with a median of 3 prior systemic therapies (range 1 to 12). The objective response rate (ORR) was 29% (by central review) and 39% (by investigator assessment), with a median duration of response (DoR) of 8.1 months (by investigator) and 10.1 months (by central review). The present analysis was conducted to assess the efficacy of pralatrexate as a second-line treatment post-CHOP. Methods: Of the 109 patients who were treated with pralatrexate and evaluable for efficacy in the PROPEL study, a subset of 15 patients received pralatrexate (30 mg/m2 intravenously weekly for 6 of 7 week cycles) as their second-line treatment post-CHOP. Results: The demographics and disease characteristics of the 15 patients treated with pralatrexate in the second-line setting post-CHOP were reflective of the overall PROPEL patient population. Nine of 15 patients (60%) were male. Median age was 60 years. Eleven of the 15 patients had a prior response to CHOP (7 CR and 4 PR). The additional 4 patients had 1 SD and 3 PD, respectively. A summary of pralatrexate efficacy as second-line treatment post-CHOP is presented in the table below. CR=complete response; CRu=complete response unconfirmed; PR=progressive disease; SD=stable disease; PD=progressive disease; DoR=duration of response; PFS=progression-free survival; OS=overall survival. The 15 patients treated in second-line post-CHOP received a median of 16 doses of pralatrexate, for a median of 134 days. Only 1 patient had a grade 4 adverse event (AE) (sepsis) and the only grade 3 AEs to occur in 〉1 patient were thrombocytopenia (4 patients), and mucosal inflammation (3 patients). Two patients discontinued treatment with pralatrexate due to AEs. Two of the 15 patients remained on treatment (time on treatment = 12.9 and 18.5 months) and in response as of the data cut-off (August 2009), and their DoR data were censored. An additional 2 patients proceeded to stem cell transplant (SCT) after response to pralatrexate, and thus were censored for DoR (at 2.3 and 3.3 months). These 2 patients remain in CR and their current disease-free period (DoR: pralatrexate + SCT) is 20.1 and 21.7 months. The PROPEL study also collected information on response to therapies administered prior to study entry. Of note, 33 patients received combination chemotherapy as their second-line systemic treatment post-CHOP (ICE and DHAP being the most common regimens): the ORR for combination therapy was 33% and the median duration on treatment for responders was 4 months, which is substantially shorter compared with the DoR to pralatrexate (median 12.5 months, per investigators assessment). Conclusions: Pralatrexate administered as second-line treatment (post-CHOP) to patients with PTCL demonstrated high activity with durable responses, including CRs leading in some patients to SCT. Pralatrexate efficacy and safety profile compared favorably with combination chemotherapy in this disease setting. Taken together, this data suggests that pralatrexate is a highly effective, single-agent, second-line therapeutic option for patients with PTCL, including those who are candidates for bone marrow transplantation. Disclosures: Shustov: Allos Therapeutics, Inc.: Honoraria, Research Funding. Pro: Allos Therapeutics, Inc.: Research Funding. Gisselbrecht: Allos Therapeutics, Inc.: Research Funding. Lechowicz: Allos Therapeutics, Inc.: Consultancy; Celgene Corporation: Consultancy. Zain: Allos Therapeutics, Inc.: Speakers Bureau. Furman: Allos Therapeutics, Inc.: Research Funding. Fruchtman: Allos Therapeutics, Inc.: Employment. Horwitz: Allos Therapeutics, Inc.: Consultancy, Research Funding. O'Connor: Allos Therapeutics, Inc.: Research Funding.

Description: Based on encouraging phase 2 data, we are prospectively testing the combination of tacrolimus and sirolimus (tacro/siro) as GVHD prophylaxis in patients undergoing HLA-MRD HCT. Seventy patients evaluable for this report (〉100 days post-HCT) were stratified according to preparative regimen as follows: Fludarabine/melphalan (38), FTBI/VP-16 (23), and Bu/Cy (9). Regimens were given through day -4; tacro/siro was started on day -3 and dosed as published (Cutler et al, BBMT 10 (5), 328–336, 2004). Median age was 50 years (range, 10–67). Diagnoses by regimen were flu/mel: AML (16), NHL (7), MPD (4), HD (4), MM (3), MDS (2), ALL (1), CLL (1); FTBI/VP-16: ALL (12), AML (10), NHL (1); and Bu/Cy: CML (5), MDS (3), AML (1). Stem cell source was PB (n=66) and bone marrow (n=4). Donor gender F:M was 34:36. Median CD34+ cell dose was 5.1 x 106/kg. Median time to neutrophil 〉500/ml was 15 days (range, 10–26); median day 30 bone marrow MNC chimerism was 100% (65–100%). CTC toxicities 〉3 were low (2 DAH, 1 ARDS, 1 IP, 1 mucositis); as expected, mucositis was more common with FTBI/VP-16; however, therapeutic sirolimus level was similarly achieved with all conditioning regimens (median level 6.5 ng/ml, range 2.1–61 in the FTBI/VP-16 arm). Opportunistic infections included CMV reactivation (6), Aspergillus pneumonia (2), candidemia (3) and parainfluenza pneumonia (1). Reversible TTP/HUS (IWG definition) was diagnosed in 14 patients (20%) and was more common with Bu/Cy (55%) than with FTBI/VP-16 (22%) or flu/mel (11%); median tacro and siro level in patients with TTP was 9.8 and 15 ng/ml, respectively. Six patients died before day 100 from relapse (2), DAH (2) and multi-organ failure MOF (2), for a day 100 non-relapse mortality of 6%. With a median follow-up of 6 months, 60 patients are alive and 10 patients have died from progressive disease (6), MOF (2) and DAH (2). Disease-free and overall survival at day 100 are 88% and 91%, and at 1 year are 72% and 75%, respectively, with no significant differences by regimen. Acute GVHD grade 2–4 and 3–4 was observed in 25 (36%) and 13 patients (19%), respectively; by conditioning regimen, grade 2–4 acute GVHD incidence was: flu/mel, 11/38 (29%); FTBI/VP-16, 9/23 (39%); and Bu/Cy, 5/9 (56%). A temporal relationship between GVHD and TTP could not be established, with some patients developing GVHD before and others after TTP. Chronic GVHD has been diagnosed in 17/45 evaluable patients. This study shows a low TRM when tacro/siro is given with 3 different conditioning regimens; adequate sirolimus levels can be achieved even in patients with significant mucositis; a high incidence of TTP in patients conditioned with Bu/Cy suggests synergistic endothelial toxicity with this combination. Acceptable rates of acute GVHD in this study support plans for a national phase 3 study comparing tacro/siro with tacro/methotrexate.

Description: Tandem cycle high-dose melphalan (Mel) followed by Mel +/− total body radiation therapy improves progression-free (PFS) and overall survival (OS) in comparison to single cycle Mel, but is associated with 3% treatment-related mortality (TRM). We tested a new tandem regimen (THDCT) followed by maintenance therapy in order to lower TRM, while enhancing efficacy. Between 5/94 and 8/04, 114 patients (pts) were enrolled on 2 sequential studies. First, pts received Mel 150 mg/m2 [cycle 1 (C1)], oral busulfan (bu 16 mg/kg; 46 pts), and cyclophosphamide 120 mg/kg (Cy; C2); the next cohort received the same THDCT but bu was given intravenously (i.v. 12.8 mg/kg; 68 pts). All pts were to receive maintenance IF 3 million units/m2 given subcutaneously, 3 times/week. Pts participating on the 2nd study were to receive thal together with IF provided that they were not in CR at 6 months post-THDCT. Peripheral blood progenitor cell mobilization consisted of G-CSF 10 microgram/kg to procure 4 x 106 CD34+ cells/kg without (first 46 pts) or with Cy 1.5 g/m2 (last 68 pts). Pts ≤65 years, with responsive or stable MM, with