Antonello Pinto

90Yttrium-Ibritumomab-Tiuxetan as First-Line Treatment for Follicular Lymphoma: 30 Months of Follow-Up Data From an International Multicenter Phase II Clinical Trial

PURPOSE We report on a multicenter phase II trial of (90)yttrium-ibritumomab-tiuxetan ((90)YIT) as first-line stand-alone therapy for patients with follicular lymphoma (FL). PATIENTS AND METHODS Fifty-nine patients with CD20(+) FL grade 1 to 3a in stages II, III, or IV, age 50 years old or older requiring therapy were enrolled. They received (90)YIT according to standard procedure. If complete response (CR) or unconfirmed complete response (CRu) without evidence for minimal residual disease (MRD) 6 months after application of (90)YIT was achieved, patients were observed without further intervention. The same applied to patients with partial response (PR) or with stable disease (SD). Patients with CR but with persisting MRD were to receive a consolidation treatment with rituximab. Primary end point was the clinical and molecular response rate. Secondary end points were time to progression, safety, and tolerability. RESULTS Six months after treatment with (90)YIT, 56% of the patients showed a CR or CRu and 31% achieved a PR. After a median follow-up of 30.6 months, the progression-free survival (PFS) was 26 months. There was a trend for shorter PFS in patients with increased lactate dehydrogenase (LDH). Of the 26 patients who had CR 12 months after (90)YIT, only three had relapsed. Median time to next treatment has not been reached. The most common toxicities were transient thrombocytopenia and leukocytopenia. Nonhematologic toxicities never exceeded grade 2 according to Common Terminology Criteria for Adverse Events (CTCAE v2.0). CONCLUSION (90)YIT is well tolerated and achieves high response rates. Patients with increased LDH tend to relapse earlier, and individuals in remission 1 year after (90)YIT appear to have long- lasting responses.

Lessons for the clinic from rituximab pharmacokinetics and pharmacodynamics

The anti-CD20 antibody rituximab (RTX; Rituxan®, MabThera®) was the first anti-cancer antibody approved by the US Food and Drug Administration in 1997 and it is now the most-studied unconjugated therapeutic antibody. The knowledge gained over the past 15 y on the pharmacodynamics (PD) of this antibody has led to the development of a new generation of anti-CD20 antibodies with enhanced efficacy in vitro. Studies on the pharmacokinetics (PK) properties and the effect of factors such as tumor load and localization, antibody concentration in the circulation and gender on both PK and clinical response has allowed the design of optimized schedules and novel routes of RTX administration. Although clinical results using newer anti-CD20 antibodies, such as ofatumumab and obinutuzumab, and novel administration schedules for RTX are still being evaluated, the knowledge gained so far on RTX PK and PD should also be relevant for other unconjugated monoclonal antibody therapeutics, and will be critically reviewed here.

Rituximab Maintenance Compared With Observation After Brief First-Line R-FND Chemoimmunotherapy With Rituximab Consolidation in Patients Age Older Than 60 Years With Advanced Follicular Lymphoma: A Phase III Randomized Study by the Fondazione Italiana Linfomi

PURPOSE To evaluate the efficacy of rituximab maintenance in 60- to 75-year-old patients with advanced follicular lymphoma responding to brief first-line chemoimmunotherapy followed by rituximab consolidation. PATIENTS AND METHODS A total of 234 treatment-naive 60- to 75-year-old patients began chemoimmunotherapy with four monthly courses of rituximab, fludarabine, mitoxantrone, and dexamethasone (R-FND) followed by four weekly cycles of rituximab consolidation. Of these, 210 patients completed the planned treatment, and 202 responders were randomly assigned to rituximab maintenance (arm A) for 8 months, once every 2 months for a total of four doses, or to observation (arm B). RESULTS Median ages in arms A and B were 66 and 65 years, respectively. After induction and consolidation therapy, the overall response rate was 86%, with 69% complete remissions (CR). After a 42-month median follow-up from diagnosis, 3-year progression-free survival (PFS; the primary end point) and overall survival (OS) were 66% (95% CI, 59% to 72%) and 89% (95% CI, 85% to 93%), respectively. After randomization, 2-year PFS was 81% for rituximab maintenance versus 69% for observation, with a hazard ratio of 0.74 (95% CI, 0.45 to 1.21; P = .226), although this was not statistically significant. No differences between the two arms were detected for OS. Overall, the regimen was well-tolerated. The most frequent grade 3 to 4 toxicity was neutropenia (25% of treatment courses), with 13 infections. Two toxic deaths (0.8%) occurred during induction treatment. CONCLUSION A brief R-FND induction plus rituximab consolidation achieved excellent results with high CR and PFS rates, supporting the feasibility of this regimen in patients older than 60 years. A short rituximab maintenance did not achieve a statistically significant PFS improvement over observation.

Persistence of minimal residual disease in bone marrow predicts outcome in follicular lymphomas treated with a rituximab-intensive program

We assessed the prognostic value of minimal residual disease (MRD) within the ML17638 phase 3 trial from the Fondazione Italiana Linfomi, investigating the role of rituximab maintenance in elderly follicular lymphoma (FL) patients after a brief first-line chemoimmunotherapy. MRD for the bcl-2/IgH translocation was determined on bone marrow cells in a centralized laboratory belonging to the Euro-MRD consortium, using qualitative and quantitative polymerase chain reactions (PCRs). Of 234 enrolled patients, 227 (97%) were screened at diagnosis. A molecular marker (MM) was found in 51%. Patients with an MM were monitored at 8 subsequent times. Of the 675 expected follow-up samples, 83% were analyzed. Conversion to PCR negativity predicted better progression-free survival (PFS) at all post-treatment times (eg, end of therapy: 3-year PFS, 72% vs 39%; P < .007). MRD was predictive in both maintenance (83% vs 60%; P < .007) and observation (71% vs 50%; P < .001) groups. PCR positivity at the end of induction was an independent adverse predictor (hazard ratio, 3.1; 95% confidence interval, 1.36-7.07). MRD is a powerful independent outcome predictor in FL patients who receive rituximab-intensive programs, suggesting a need to investigate its value for decision-making. This trial was registered at www.clinicaltrial.gov as #NCT01144364.

Fludarabine, cytarabine, and G-CSF (FLAG) for the treatment of acute myeloid leukemia relapsing after autologous stem cell transplantation

Abstract Twenty-six patients affected by acute myeloid leukemia (AML) who relapsed after autologous stem cell transplantation (ASCT) were treated with the FLAG regimen (fludarabine, cytarabine, and G-CSF). Their median age was 39 years (range 14–59). The median interval from achievement of CR to ASCT was 4 months (2–8). The conditioning regimen was BAVC (BCNU, amsacrine, VP-16, cytarabine) in eight patients, BuCy (busulfan, cyclophosphamide) in 13, and TBI-Cy (total body irradiation, cyclophosphamide) in five. Relapse occurred after a median of 7 months (2–18). ASCT had been performed in CR1 for 23 patients and in CR2 for three. Nineteen patients had been given bone marrow, seven peripheral blood stem cells collected following consolidation plus G-CSF. Overall, CR was obtained by 13 patients (50%), all remitters requiring a single course. The median time for hematological recovery of neutrophils >500/μl and platelets >20,000/μl was 24 and 30 days, respectively. The median duration of G-CSF administration was 25 days, while the median hospitalization was 31 days. There were four deaths in induction (15%), while nine patients (35%) were resistant. After achieving CR, two patients received allogeneic BMT, five a second ASCT, and four were consolidated with HD-ARA-C. Only two patients were judged unable to receive any further therapy. There were 14 documented infections, while nine patients experienced fever of unknown origin. WHO >2 nonhematological toxicity consisted of stomatitis (50%), hepatic dysfunction (11%), diarrhea (11%), and lethargy (4%). Median overall survival and disease-free survival were 6 and 13 months, respectively. Six patients are in CCR at present. We conclude that FLAG is effective in patients with AML who are relapsing after ASCT. The toxicity is acceptable, enabling most patients to receive further treatment, including second transplantation procedures.

Fotemustine plus etoposide, cytarabine and melphalan (FEAM) as a new conditioning regimen for lymphoma patients undergoing auto-SCT: a multicenter feasibility study.

BEAM is a widely used conditioning regimen for relapsed/refractory lymphoma patients undergoing auto-SCT. We conducted a multicenter study with an alternative regimen (fotemustine plus etoposide, cytarabine and melphalan (FEAM)) in which BCNU was substituted by the chloroethylnitrosourea fotemustine (FTM). Eighty-four patients with relapsed/refractory Hodgkins (n=20) and non-Hodgkins lymphoma (n=64) were conditioned with a FEAM regimen (FTM 150 mg/m2 on days –7, –6, etoposide 200 mg/m2 and cytarabine 400 mg/m2 on days –5, –4, –3, –2 and melphalan 140 mg/m2 on day –1). Patients were evaluated for toxicity and engraftment parameters. Median times to neutrophil (>500 × 109/l) and plt (>20 000 × 109/l) engraftment were 11 and 13 days, respectively. Grade 3 mucositis occurred in 19 patients (23%), while G3 nausea/vomiting and G3 diarrhea were observed in 13 (15%) and 6 (7%) patients, respectively. No severe hepatic, renal or pulmonary toxicity was detected. Seven patients (7%) experienced G4 mucositis, while no other G4 toxicities or unexpected adverse events of any grade were recorded. Transplant-related mortality was 2.4%. We conclude that a FEAM regimen is feasible and safe. Although toxicity and engraftment times compared favorably with BEAM, longer follow-up is needed to evaluate fully its efficacy and long-term safety.

Rituximab and Subcutaneous 2-Chloro-2′-Deoxyadenosine as Therapy in Untreated and Relapsed Waldenström's Macroglobulinemia

With the aim to assess the efficacy of subcutaneous cladribine in combination with rituximab, 29 newly diagnosed/pretreated WM patients were enrolled in a multicenter phase II trial. Intended therapy consisted of rituximab on day 1 followed by s.c. cladribine 0.1 mg/kg for 5 consecutive days, administered monthly for 4 cycles. The expression of genes involved in cladribine metabolism was evaluated. With a median follow-up of 50 months the ORR rate observed was 89.6% without any difference between newly or pretreated patients (P=.522). The therapy was well tolerated; no major infections were observed, no patients developed transformation to high-grade NHL nor myelodysplasia. Low expression levels of hCNT1 correlated with the failure to achieve a CR (P=.024). The combination of rituximab/cladribine is safe and effective in WM patients requiring treatment. The pharmacogenomic analysis suggests that hCNT1 might be beneficial in predicting clinical response to such a combination treatment.

Improved outcome of patients with relapsed/refractory Hodgkin lymphoma with a new fotemustine‐based high‐dose chemotherapy regimen

High‐dose chemotherapy (HDT) with autologous stem cell transplantation is the standard of care for relapsed/refractory (RR) Hodgkin lymphoma (HL). Given that HDT may cure a sizeable proportion of patients refractory to first salvage, development of newer conditioning regimens remains a priority. We present the results of a novel HDT regimen in which carmustine was substituted by a third‐generation chloroethylnitrosourea, fotemustine, with improved pharmacokinetics and safety (FEAM; fotemustine, etoposide, cytarabine, melphalan) in 122 patients with RR‐HL accrued into a prospective registry‐based study. Application of FEAM resulted in a 2‐year progression‐free survival (PFS) of 73·8% [95% confidence interval (CI), 0·64–0·81] with median PFS, overall survival and time to progression yet to be reached. The 2‐year risk of progression adjusted for the competitive risk of death was 19·4% (95% CI, 0·12–0·27) for the entire patient population. Most previously established independent risk factors, except for fluorodeoxyglucose (18FFDG)‐uptake, were unable to predict for disease progression and survival after FEAM. Although 32% of patients had 18FFDG‐positrin emission tomography‐positive lesions before HDT, the 2‐year risk of progression adjusted for competitive risk of death was 19·4% (95% CI; 0·12–0·27). No unusual acute toxicities or early/late pulmonary adverse events were registered. FEAM emerges as an ideal HDT regimen for RR‐HL patients typically pre‐exposed to lung‐damaging treatments.

Brentuximab Vedotin in Transplant-Naïve Relapsed/Refractory Hodgkin Lymphoma: Experience in 30 Patients

BACKGROUND Hodgkin lymphoma (HL) is characterized by the presence of CD30-positive Hodgkin Reed-Sternberg cells. Approximately 30%-40% of patients with advanced disease are refractory to frontline therapy or will relapse after first-line treatment. The standard management of these patients is salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell transplant (ASCT). The best prognostic factor is the status of disease before ASCT; in particular, the normalization of positron emission tomography (PET) scan. Brentuximab vedotin (BV) has shown a high overall response rate in refractory/relapsed HL after ASCT, whereas few data are available regarding its role before ASCT. PATIENTS AND METHODS A multicenter, retrospective, observational study was conducted. The primary endpoint of the study was the effectiveness of BV as single agent in patients with relapsed/refractory, ASCT-naïve HL, determined by the conversion of PET status from positive to negative; secondary endpoints were safety, capacity to proceed to ASCT, survival, and progression-free status. RESULTS Thirty patients with relapsed/refractory HL- and PET-positive disease after conventional chemotherapy salvage treatments were treated with a median of 4 cycles of BV. Normalization of PET findings (Deauville score ≤2) occurred in 9 of 30 patients (30%). Those nine patients proceeded to ASCT. CONCLUSION These data suggest that BV can normalize PET status in a subset of HL patients refractory to conventional chemotherapy salvage treatments, such as ifosfamide-containing regimens, cytarabine- and platinum-containing regimens, prior to ASCT.

Efficacy of 90Yttrium‐ibritumomab tiuxetan in relapsed/refractory extranodal marginal‐zone lymphoma

We evaluated clinical activity of 90Yttrium‐ibritumomab (90Y‐ibritumomab) tiuxetan in extranodal marginal‐zone lymphoma. From May 2004 to April 2011, 30 patients affected by relapsed/refractory marginal‐zone lymphoma—arisen at any extranodal site—received 90Y‐ibritumomab tiuxetan at the activity of 0.4 mCi/kg. Median age was 57 years. At time of treatment, 13 out of 30 patients had disseminated disease (stage III/IV). All patients had received a previous treatment with a maximum of 7. Overall response rate was 90%: 23 patients achieved a complete response (77%); partial response occurred in 4 patients (13%), stable disease in 2 patients (7%) and 1 progression (3%). With a median follow‐up of 5.3 years, median time to relapse was not reached; 2 patients relapsed after complete response; 18 out of 23 complete responses are still responders after >3 years, 12 of them after >5 years. 90Y‐ibritumomab tiuxetan seems to be active in patients with extranodal marginal‐zone lymphoma relapsed/refractory to conventional treatment including radiotherapy. These results suggest that radioimmunotherapy could represent a possible option for the treatment in this subset of patients. Copyright