Preliminary results of a phase I/II study of weekly or twice weekly bortezomib in combination with rituximab, in patients with follicular lymphoma, mantle cell lymphoma and Waldenström's macroglobulinaemia

Introduction: Rituximab (R) is an integral component of therapy for B-cell lymphoid malignancies; bortezomib (Btz) has shown provocative single agent activity in Follicular Lymphoma (FL), Mantle Cell Lymphoma (MCL) and Waldenström’s Macroglobulinaemia (WM), providing the rationale for investigating the combination. Patients+Methods: Forty-five adult patients (pts.) (30 men, 15 women) with histologically confirmed recurrent CD20+ve FL, MCL or WM, median age 60 years (range 45-79), FL: 17, MCL: 18, WM: 10, stage III/IV 40 (93%), bone marrow (BM) infiltration 32 (73%), elevated LDH 22 (49%), performance status 1 22 (49%), were enrolled in a randomised trial comparing 2 schedules of Brz+R: Arm A (twice weekly) Btz: 1.3mg/m2 (on days 1, 4, 8, 11 of a 21-day cycle) and R: 375mg/m2 (on day 1) for 8 cycles, or Arm B (weekly) Btz: 1.6mg/m2 (on days 1, 8, 15, 22 of a 35-day cycle) and R: 375mg/m2 (on days 1, 8, 15, 22 of cycles 1 and 4) for 6 cycles (23 arm A, 22 arm B). The median number of previous treatments was 2 (range 1-7). Seventeen pts. had received a R-containing regimen, with response lasting >6 months, and 8 high-dose treatment. Response was evaluated using the IWR criteria (Cheson et al, JCO17: 1244, 1999) and the updated response criteria from the 3rd International Workshop on WM (Treon et al, Blood107: 3442, 2006) Results: Ability to deliver the therapy, toxicity and efficacy were equivalent in both arms. The median number of cycles given in arm A was 4 and 5 in arm B. Haematological toxicity (grade3: anaemia 0%, neutropenia 25%, thrombocytopenia 22%) was significantly influenced by the high percentage of pts. with BM infiltration and concomitant cytopenia on entry to the trial. The most common non-haematological adverse events were fatigue (76%), nausea (56%), diarrhoea (56%), lethargy (46%). Neurotoxicity occurred in 19 pts. (46%) (10 pts. grade 1, 7 pts. grade 2, 2 pts. grade 3). Btz dose was reduced in 7 pts.; 5 doses were omitted because of neuro or haematological toxicity. In 16 pts., treatment was delayed by 1-14 days and in 24 pts. treatment was stopped prematurely. The reasons for stopping treatment were: treatment-related toxicity 11 pts., progressive disease 9 pts., patient’s preference 3 pts., myocardial infarction 1 pt. One pt. was excluded having been found ineligible post randomisation. Thirty-nine pts. (21 arm A, 18 arm B) are evaluable for response so far, one having only received 1 cycle of therapy, which had to be discontinued because of excessive toxicity. 15/32 were in remission (CR, CRu, PR) at the completion of therapy, 7/7 at "mid-therapy" assessment, and 5 have yet to be evaluated. Thus the overall response rate (RR) presently is 22/39 (56%) (CR, CRu, PR), FL 44%, MCL 46%, WM 90%. Conclusions: The combination was active in pts. with recurrent NHL especially WM (RR 90%), despite multiple previous treatments, The weekly schedule is preferable being more convenient, as efficacious and no more toxic. Further investigation is warranted, despite not insignificant therapy compromising toxicity

Tositumomab and iodine I 131 tositumomab for recurrent indolent and transformed B-cell non-Hodgkin's lymphoma

Purpose: an open-label phase II study was conducted at two centers to establish the efficacy and safety of tositumomab and iodine I 131 tositumomab at first or second recurrence of indolent or transformed indolent B-cell lymphoma.Patients and methods: a single dosimetric dose was followed at 7 to 14 days by the patient-specific administered radioactivity required to deliver a total body dose of 0.75 Gy (reduced to 0.65 Gy for patients with platelets counts of 100 to 149 x 109/L). Forty of 41 patients received both infusions.Results: thirty-one of 41 patients (76%) responded, with 20 patients (49%) achieving either a complete (CR) or unconfirmed complete remission [CR(u)] and 11 patients (27%) achieving a partial remission. Response rates were similar in both indolent (76%) and transformed disease (71%). The overall median duration of remission was 1.3 years. The median duration of remission has not yet been reached for those patients who achieved a CR or CR(u). Eleven patients continue in CR or CR(u) between 2.6+ and 5.2+ years after therapy. Therapy was well tolerated; hematologic toxicity was the principal adverse event. Grade 3 or 4 anemia, neutropenia, and thrombocytopenia were observed in 5%, 45%, and 32% of patients, respectively. Secondary myelodysplasia has occurred in one patient. Four patients developed human antimouse antibodies after therapy. Five of 38 assessable patients have developed an elevated thyroid-stimulating hormone; treatment with thyroxine has been initiated in one patient.Conclusion: high overall and CR rates were observed after a single dose of tositumomab and iodine I 131 tositumomab in this patient group. Toxicity was modest and easily manage