Introduction
RCHOP is the standard frontline treatment for patients with DLBCL. However, for patients with high-intermediate or high-risk disease (IPI 3-5), outcomes are suboptimal, with an estimated ...3-year PFS of about 55%. In addition to IPI, an additional factor associated with an increased risk include non-GCB cell of origin. Brentuximab vedotin, an ADC targeting CD30, has demonstrated single-agent activity in relapsed/refractory DLBCL patients. Of note, higher ORR and CR, as well as longer duration of PFS, were observed in those patients with CD30 detected on tumor cells by routine IHC.
Methods
This phase 2 study was designed to evaluate combination therapy using brentuximab vedotin (BV) and standard RCHOP chemotherapy as frontline treatment in patients with high-intermediate/high risk (standard IPI score 3-5 or age-adjusted IPI aaIPI score 2-3) DLBCL, regardless of CD30 expression (ClinicalTrials.gov NCT01925612). Patients were randomized to receive either 1.2 mg/kg BV+RCHOP or 1.8 mg/kg BV+RCHOP for up to 6 cycles of treatment. BV was given on Day 1 of every 21-day cycle. Response was assessed per investigator using Cheson 2007. AEs, physical examination findings, and laboratory testing were utilized to characterize safety. Tumor cell CD30 expression was measured by IHC and gene expression analysis; soluble CD30 was measured in plasma. Tumor microenvironment was also evaluated for frequency of immune-infiltrating cells.
The primary endpoints for this study were the tolerability of each regimen and the CR rate at the end of treatment (EOT). Key secondary endpoints included progression-free survival (PFS). Additional exploratory endpoints included CD30 expression on tumor specimens (CD30- defined as <1% per IHC) and correlation of CD30 expression and response.
Results
Twenty-nine patients were treated with 1.2 mg/kg BV+RCHOP and 22 patients were treated with 1.8 mg/kg BV+RCHOP. Over half (63%) were high-intermediate risk (IPI 3, aaIPI 2) and 37% were high risk (IPI 4-5, aaIPI 3). Most had Stage IV disease (71%) and 27% had an ECOG score of 2. AEs in ≥50% of patients included peripheral sensory neuropathy (63%), fatigue (61%), nausea (55%), and diarrhea (53%). Grade 3 or higher events occurred in 76% of patients; the most frequent were neutropenia (33%) and febrile neutropenia (31%).
The PET-negative CR rate was 69% overall; CD30+ patients had a CR rate of 76% (19/25) compared with 63% (12/19) in CD30- patients by IHC. Although PFS data are still immature (median follow up of 8 months), the estimated PFS rate at 12 months was 82% (95% CI: 58, 93) in CD30+ patients and 56% (95% CI: 32, 75) in CD30- patients. 60% (3/5) of patients with CD30- ABC-DLBCL progressed versus 27% (3/11) of CD30+ ABC-DLBCL patients. Four patients with EBV+ DLBCL were treated and all achieved CR; 3 EBV+ patients remain in remission after a median follow-up of 12 months.
Within the microenvironment, a higher percentage of CD3+ T-cells was observed in patients with CR (23%; range, 4-80%) than in those with PR (14%; range, 10-15%) or PD (11%; range, 5-15%). Of the 32 patients who have not yet progressed, 50% had ≥20% CD3+ cells compared to 18% of patients with PD (2/11). Other factors, including soluble CD30 levels and infiltrating CD68+ cells, were not associated with clinical outcomes.
Conclusions
Interim results demonstrate that adding BV to RCHOP results in a high rate of CR in this population of IPI 3-5 DLBCL. Patients with CD30-expression in the tumor appear to have a higher CR rate and fewer early progression events than patients with CD30- DLBCL. Furthermore, subsets of patients who have a particularly poor prognosis (CD30+ ABC subtype and EBV+ DLBCL) appeared to have a favorable outcome with BV+RCHOP. Evaluation of the tumor microenvironment showed that higher frequencies of infiltrating CD3+ cells were observed in the CR group, suggesting possible immunologic correlates of response. However, CD30 expression appears to have greater prognostic significance in this study despite the relatively small sample size. These results are intriguing and merit further testing in a randomized trial.
Yasenchak:Seattle Genetics, Inc.: Research Funding. Off Label Use: Brentuximab vedotin is indicated in the US for treatment of patients with Hodgkin lymphoma after failure of autologous stem cell transplant or after failure of at least two prior multi-agent chemotherapy regimens in patients who are not ASCT candidates and for the treatment of patients with systemic anaplastic large cell lymphoma after failure of at least one prior multi-agent chemotherapy regimen. The drug is being evaluated in this study for use as frontline treatment in patients with high-intermediate/high risk DLBCL in combination with multiagent chemotherapy. . Halwani:Abbvie: Research Funding; Pharmacyclics: Other: Travel expenses, Research Funding; Takeda/Millenium: Research Funding; BMS: Research Funding; Seattle Genetics, Inc.: Other: Travel expenses, Research Funding; Roche/Genentech: Research Funding; Kyowa Hakko Kirin: Research Funding; Amgen: Research Funding. Advani:Seattle Genetics, Inc.: Research Funding; Genetech: Consultancy. Ansell:Bristol-Myers Squibb: Research Funding; Celldex: Research Funding. Budde:Merck: Research Funding; Ikara Inc: Patents & Royalties; Atara Biotherapeutics: Consultancy; Seattle Genetics, Inc.: Research Funding. Burke:Millenium/Takeda: Consultancy; Incyte: Consultancy; TG Therapeutics: Other: Travel expenses; Gilead: Consultancy; Janssen: Consultancy; Seattle Genetics, Inc.: Research Funding. Farber:Seattle Genetics, Inc.: Research Funding. Holkova:Seattle Genetics, Inc.: Research Funding. Kolibaba:GSK: Research Funding; Seattle Genetics, Inc.: Research Funding; Acerta: Research Funding; Celgene: Research Funding; Gilead: Consultancy, Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Genentech: Research Funding; Pharmacyclics: Research Funding; Janssen: Research Funding; TG Therapeutics: Research Funding. Knapp:Celgene: Research Funding; Heron Pharmaceuticals: Other: Travel expenses, Research Funding; Merck: Research Funding; Seattle Genetics, Inc.: Research Funding; Takeda Pharmaceuticals International Co.: Research Funding; Brystol-Myers Squibb: Research Funding; Genentech: Honoraria, Other: Travel expenses, Research Funding; Pharmacyclics LLC, an AbbVie Company: Research Funding; EMD Serono: Research Funding. Li:Seattle Genetics, Inc.: Employment, Equity Ownership. Manley:Seattle Genetics, Inc.: Employment, Equity Ownership. Patel-Donnelly:Seattle Genetics, Inc.: Research Funding. Seetharam:Seattle Genetics, Inc.: Research Funding. Yimer:Seattle Genetics, Inc.: Research Funding. Bartlett:Gilead: Consultancy, Research Funding; Janssen: Research Funding; Pharmacyclics: Research Funding; Genentech: Research Funding; Pfizer: Research Funding; Novartis: Research Funding; Millennium: Research Funding; Colgene: Research Funding; Medimmune: Research Funding; Kite: Research Funding; Insight: Research Funding; Seattle Genetics: Consultancy, Research Funding; MERC: Research Funding; Dynavax: Research Funding; Idera: Research Funding; Portola: Research Funding; Bristol Meyers Squibb: Research Funding; Infinity: Research Funding; LAM Theapeutics: Research Funding.
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High dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a standard of care for patients with advanced or treatment refractory multiple myeloma (MM) and non-Hodgkin ...lymphoma (NHL). Stem cell proliferation and mobilization can be enhanced though the addition of myelosuppressive chemotherapy prior to GCSF administration. Chemotherapeutic agents without cross resistance to prior therapies may support peripheral blood stem cell (PBSC) collection and improve patient outcomes by exacting a more potent direct anti-tumor effect prior to ASCT. Bendamustine (Treanda®) is a synthetic chemotherapeutic agent that shares structural similarities to both purine analog and alkylating agents without significant cross resistance to other compounds in either drug class. Bendamustine appears to have low stem cell toxicity in vitro, is well tolerated, and has activity in MM and NHL, but the potential for the purine moiety to adversely impact stem cell reserve is unknown. We hypothesized that bendamustine's activity in patients with disease resistant to first line therapies makes it a logical candidate for chemotherapy based PBSC mobilization and tested its impact on stem cell yield.
Patients were eligible if they had relapsed or refractory MM, B-cell NHL or T-cell NHL and were candidates for ASCT. Other criteria included: age >18 years, ANC >1,500/mm3, platelets >100,000/mm3, adequate renal and hepatic function, <3 prior myelotoxic regimens, <6 cycles of lenalidomide, no failed mobilization attempt, and no prior pelvic/spinal irradiation. Patients received 1 cycle of BED therapy bendamustine (120 mg/m2 IV d 1, 2 - provided along with financial support for this study by Teva Pharmaceuticals), etoposide (200 mg/m2 IV d 1- 3), dexamethasone (40 mg PO d 1- 4), delivered as an outpatient, followed by filgrastim (initially 10 mcg/kg/d sc; starting on d 5 through end of collection). Apheresis was initiated when peripheral blood CD34 cell counts were >5/µL. The primary endpoint was successful mobilization, defined as collection of >2.0 x 106CD34 cells/kg. AEs were graded using the CTCAE v4.0.
Thirty-seven patients (32 MM, 4B-cell NHL, 1 NK/T-cell NHL) were treated. The median age was 60 years (range 43-70). The median number of prior therapies was 1 (range 1-3) for MM and 2 (range 1-3) for NHL patients. All patients (37/37) were successfully mobilized. The median number of CD34+ cells collected was 19.43 x 106/kg (range 4.35 to 55.51 x 106). All MM patients collected >10 x 106 CD34+cells/kg. The median time from the start of BED mobilization therapy to the first day of CD34 stem cell collection was 12 days (range 9 to 20 days). The median number of apheresis days was 1 (range 1 to 4). A predictable pattern of leucocyte nadir and recovery was demonstrated (95% of patients started apheresis between days 9-13). Two patients (5%) were given plerixafor and for 2 patients (5%) GCSF was increased to 16 mcg/kg twice daily. Among the 37 patients mobilized and collected, 31 have thus far undergone ASCT and 100% (31/31) achieved an unsupported neutrophil count >500/µL at a median of 15 days (range 7-19) after PBSC infusion and a platelet count >20K/µL at a median of 11 days (range 8-14). Ten SAEs were observed in 8 patients and 1 patient died due to disease progression prior to ASCT. SAEs include: neutropenic fever (1, grade GR 3), bone pain (2, GR 3), renal insufficiency (1, GR 1), atrial fibrillation (1, GR 2), hypotension (1, GR 3), stroke (1, GR 2), and one patient accounted for 3 SAEs including GR 3 tumor lysis syndrome and sepsis and GR 5 disease progression. Among twenty-nine evaluable patients to date, responses include: CR= 4 PR=2, SD=19 and PD=4. The ORR to this single cycle of therapy was 21%.
PBSC mobilization with BED is safe and effective. BED is not an acute stem cell toxin. Large numbers of stem cells were rapidly mobilized and resulted in short durations of apheresis. No patient with MM collected <10 x 106 CD34+ cells/kg (sufficient for 2 ASCTs). Twenty-one percent of patients demonstrated a measurable response to a single cycle of BED therapy and an additional 65% of patients had stable disease. In patients who were transplanted, the time to neutrophil and platelet engraftment was comparable to other chemotherapy based mobilization regimens. The BED regimen was well tolerated and these findings suggest that the role of BED in PBSC mobilization should be further explored.
No relevant conflicts of interest to declare.
Abstract ▪4126▪This icon denotes a clinically relevant abstract
High dose chemotherapy followed by autologous stem cell transplantation (ASCT) is a standard of care for patients with advanced or ...treatment refractory multiple myeloma (MM) and non-Hodgkin lymphoma (NHL). Stem cell proliferation and mobilization can be enhanced though the addition of myelosuppressive chemotherapy to GCSF administration. Chemotherapeutic agents without cross resistance to prior therapies may support peripheral blood stem cell (PBSC) collection and improve patient outcomes by exacting a more potent direct anti-tumor effect prior to ASCT. Bendamustine (Treanda®) is a synthetic chemotherapeutic agent that shares structural similarities to both purine analog and alkylating agents without significant cross resistance to other compounds in either drug class. Bendamustine appears to have low stem cell toxicity in vitro, is well tolerated, and has activity in MM and NHL. We hypothesized that bendamustine’s activity in patients with disease resistant to first line therapies makes it a logical candidate for chemotherapy based PBSC mobilization.
Patients were eligible if they had relapsed or refractory MM, B-cell NHL or T-cell NHL and were candidates for ASCT. Other criteria included: age >18 years, ANC >1,500/mm3, platelets >100,000/mm3, adequate renal and hepatic function, <3 prior myelotoxic regimens, <6 cycles of lenalidomide, no prior failed mobilization attempt, and no prior pelvic/spinal irradiation. Patients received 1 cycle of BED therapy bendamustine (120 mg/m2 IV d 1, 2 - provided along with financial support for this study by Teva Pharmaceuticals), etoposide (200 mg/m2 IV d 1– 3), dexamethasone (40 mg PO d 1– 4), delivered as an outpatient, followed by filgrastim (10 mcg/kg/day; starting on d 5 through end of collection). Apheresis was initiated when peripheral blood CD34 cell counts were >5/μL. The primary endpoint was successful mobilization, defined as collection of >2.0 × 106CD34 cells/kg. Adverse events (AEs) were graded using the CTCAE v4.0.
Twenty patients (16 MM, 3 B-cell NHL, 1 NK/T-cell NHL) were treated. The median age was 59 years (range 43–70), and the median number of prior therapies was 1 (range 1–3) for MM and 2 (range 2–3) for NHL patients. All patients (20/20) were successfully mobilized. The median number of CD34+ cells collected was 19.11 × 106/kg (Mean 22.49; range 4.35 to 55.51 × 106). All MM patients collected >10 × 106 CD34+cells/kg. The median time from BED mobilization therapy to the first day of CD34 stem cell collection was 12 days (mean 12.05; range 10 to 20 days). The median number of days of apheresis was 1 (mean 1.45; range 1 to 4). A predictable pattern of leucocyte nadir and recovery was demonstrated (88% of patients started apheresis between days 10–12). One patient (5%) was given plerixafor and for 2 patients (10%) the dose of GCSF was increased to 16 mcg/kg twice daily. Among the 20 patients mobilized and collected, 12 have thus far undergone ASCT and 100% (12/12) have achieved an unsupported neutrophil count >500/μL at an average of 14.3 days after PBSC infusion and a platelet count >20K/μL at an average of 10 days. Serious AEs (SAEs) were observed in 5 patients and 1 patient died due to disease progression. No unexpected grade 3 or greater treatment related SAEs were seen. Disease response assessments are ongoing. The original protocol design involved 3 agents (bendamustine, dexamethasone and GCSF BDG). After the first 3 patients enrolled, the mobilization regimen was modified to include etoposide because BDG did not yield a predictable pattern of leucocyte nadir and recovery, thus complicating timing for apheresis (median time to collection 22 days). The first 3 patients were censored from the analysis, however all 3 patients were successfully mobilized and collected.
The initial experience with PBSC mobilization after BED in this phase II study suggests the regimen is safe and effective, while the use of BDG does not yield predictable CD34 kinetics. Time to neutrophil and platelet engraftment after ASCT appears unimpaired when compared with other chemotherapy based mobilization regimens. Large numbers of stem cells were rapidly mobilized and resulted in short durations of apheresis. No patient with MM collected <10 × 106 CD34+ cells/kg (sufficient for 2 ASCTs). The regimen was very well tolerated and these findings suggest that the role of bendamustine in PBSC mobilization should be further explored.
Green:Teva Pharmaceuticals: Research Funding. Holmberg:Millenium: Research Funding; Otsuka: Research Funding; Merck: Research Funding; Seattle Genetics: Research Funding; Sanofi: Research Funding. Budde:Teva Pharmaceuticals: Research Funding. Gopal:Teva Pharmaceuticals: Research Funding.
