Maximum Tolerated Dose Of Bortezomib Research Articles

A Phase 1/2, Open-Label, Prospective, Multicenter Study to Evaluate the Efficacy and Safety of the Lower Dose of Bortezomib Plus Busulfan and Melphalan As a Conditioning Regimen in Patients with Multiple Myeloma Undergoing Autologous Peripheral Blood Stem Cell Transplantation: Result of Phase 1 Trial

AbstractAbstract 1937 Background:Despite the advantages of autologous stem cell transplantation (ASCT) over conventional chemotherapy, the results of ASCT in multiple myeloma (MM) are still unsatisfactory. Intravenous (iv) melphalan at a dose of 200 mg/m2 is the most commonly used conditioning regimen for ASCT. However, better conditioning regimens are still needed, and more intensive conditioning regimens have been investigated. We evaluated the role of bortezomib-containing regimen (escalated dose of bortezomib + iv busulfan and iv melphalan) in the MM patients who had a sensitive response to bortezomib during the induction chemotherapy. In the phase 1 trial, we assessed the MTD (maximum tolerated dose) of bortezomib. The trial is registered on National Cancer Institute website, number NCT01255527. Methods:Nine MM patients who were candidate for ASCT enrolled in this study. M:F=5:4 and median age were 59 (34–62). They were treated with escalating doses of bortezomib as a conditioning regimen (N=3/group; 0.7, 1.0, and 1.3 mg/m2 on D-6, D-3 & D+1) and a fixed dose of busulfan (3.2 mg/kg from D-5 to D-3) and melphalan (140 mg/m2 on D-2). Dose limiting toxicities (DLT) were defined as any toxicity of grade 3 or greater, with the following exceptions: vomiting, fatigue, alopecia, libido, amenorrhea, nausea, febrile neutropenia, infection, anorexia, depression, anxiety, and cytopenias. Grade 3/4 hematological toxicity was acceptable. Grade 4 of mucositis, °Ã Grade 3 diarrhea and °Ã Grade 3 cardiac toxicity were regarded as DLT. Only one patients had grade 3 oral mucositis and there were no other non hematologic toxicities of grade 3 or greater. DLT refers only to toxic events (symptomatic grade °Ã 3 toxicity) that occur until day +28 after ASCT and are attributed as possibly, probably, or definitely due to treatment. Results:Four patients had grade 3 oral mucositis (2 in 0.7 mg/m2 group, 1 in 1.0 mg/m2 group and 1 in 1.3 mg/m2 group), but no grade 4 (considered as DLT) oral mucositis. No other non hematologic toxicities of grade 3 or greater. Therefore, there were no dose limiting toxicities in this phase 1 trial and MTD of bortezomib was 1.3 mg/m2. Median times to ANC > 0.5 · 106/L and platelet > 20 · 106/L were 12 and 10 days, respectively, with no graft failures. All patients achieved at least very good partial response. Six patients (67%) achieved complete remission(CR) after ASCT. Conclusion:In the phase 1 trial, MTD of bortezomib was 1.3 mg/m2. Addition of bortezomib to busulfan and melphalan conditioning regimen shows to be safe, well-tolerated and worthy of phase 2 trial. [Display omitted] [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Bortezomib May Be Safely Combined with Y-90 Ibritumomab Tiuxetan In Patients with Relapsed/Refractory Follicular or Transformed Non-Hodgkin Lymphoma: A Phase I Trial of Combined Induction Therapy and Bortezomib Consolidation

AbstractAbstract 1749 Background:Preclinical studies suggest that bortezomib, through inhibition of NF-kB activation, may act as a radiosensitizer and enhance the effects of radioimmunotherapy. Methods:This phase I trial was designed to determine the maximum tolerated dose (MTD) of weekly bortezomib induction combined with Y-90-ibritumomab tiuxetan in patients 18 years or older with relapsed/refractory follicular or transformed non-Hodgkin lymphoma. In addition, we assessed the tolerability of weekly bortezomib consolidation following induction therapy. Cohorts consisting of three patients each were treated with bortezomib induction at doses of 1.0, 1.3, or 1.6 mg/m2 on days 1, 8, 15, and 22, rituximab 250 mg/m2 on days 8 and 15, and Y-90 ibritumomab tiuxetan 0.4 mCi/kg on day 15. Consolidation, consisting of bortezomib 1.6 mg/m2 weekly on days 1, 8, and 15 of three 28 day cycles, was initiated on day 71 after recovery of the platelet count to 100,000/uL and ANC> 1,000/uL. At least three patients per cohort were followed for 7 weeks or had recovery of blood counts without dose-limiting toxicities (DLTs) before dose escalation was allowed. MTD was defined as the dose previous to that in which two patients had DLTs. To be evaluable, patients were required to have received at least two doses of bortezomib and the Y-90-ibritumomab tiuxetan therapeutic dose. Response was assessed by CT scanning following induction therapy and PET/CT and diagnostic CT scans after completion of consolidation. Results:Nine patients with a median age of 55 (range: 29–71) were treated with bortezomib combined with Y-90-ibritumomab tiuxetan. Eight patients had FL and one had evidence of a transformation to diffuse, large B-cell lymphoma. All had a performance status of 0 or 1, and all had been previously treated with rituximab either as a single agent or in combination with chemotherapy. All but one had received prior chemotherapy [R-CHOP (n=7), chlorambucil (n=1), or R-CVP (n=2)], and three had received radiotherapy. Only one had bone marrow involvement. The median number of prior therapies was one (range: 1–3). Grade 3 or 4 toxicities were observed in all but one of the patients and as expected, all but one of these toxicities were hematologic (leukopenia, lymphopenia, neutropenia, and/or thrombocytopenia). One patient had grade 3 cardiotoxicity characterized by palpitations and shortness of breath on day 15 of her first consolidation, with PVC's noted on subsequent EKG. Though uncommon, cardiotoxicity has been reported in association with bortezomib in the form of systolic heart failure, arrhythmias, and angina. It should be noted that this patient was previously treated with an anthracycline as have the majority of patients reported to have experienced cardiotoxicity in association with bortezomib. A DLT of grade 4 thrombocytopenia lasting more than ten days was observed in two of three patients treated with bortezomib at 1.6 mg/m2. One of these two patients was the only one to receive .3 mCi/kg rather than .4 mCi/kg of the radioisotope because of thrombocytopenia on the day of treatment. Thus, the MTD of bortezomib was 1.3 mg/m2. All patients are alive, and the median followup for those patients who have not progressed is 6.5 months (range: 3 – 15 mo.). All but one patient responded to therapy (4 CR/CRu, 4PR, 1 SD). The four complete responders remain in remission at 3.0, 5.0, 5.0 and 15.0 months. All of the partial responders have progressed (3.5, 3.5, 11.5, and 17.5 months), as has the patient with stable disease (5.0 months). Conclusions:The MTD for weekly bortezomib combined with Y-90 ibritumomab tiuxetan induction therapy is 1.3 mg/m2. Consolidation with bortezomib at 1.6 mg/m2 was well tolerated in this group of relapsed/refractory follicular and transformed non-Hodgkin lymphoma patients. Nearly all patients responded. A phase II trial at the MTD is underway to better define the toxicity and effectiveness of this regimen in patients with relapsed/refractory FL. Disclosures:Evens:Millenium: Membership on an entity's Board of Directors or advisory committees, Research Funding; Spectrm: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Ziopharm: Membership on an entity's Board of Directors or advisory committees; Lilly: Research Funding; Ortho- Biotec: Research Funding; Celgene: Membership on an entity's Board of Directors or advisory committees; Seattle Genetics: Membership on an entity's Board of Directors or advisory committees. Gordon:Cure Tech, Ltd: Membership on an entity's Board of Directors or advisory committees; Pharmacyclics, Inc: Research Funding; Genentech: Speakers Bureau; Millenium: Research Funding; Spectrum: Membership on an entity's Board of Directors or advisory committees. Winter:Millenium: Consultancy, Research Funding; Pfizer/Wyeth: Research Funding; Novartis: Consultancy, Research Funding; Genentech: Research Funding; Seattle Genetics: Research Funding; Spectrum: Honoraria.

A Phase I Study of Bortezomib in Combination With Standard 5-Fluorouracil and External-Beam Radiation Therapy for the Treatment of Locally Advanced or Metastatic Rectal Cancer

Standard therapy for stage II/III rectal cancer consists of a fluoropyrimidine and radiation therapy followed by surgery. Preclinical data demonstrated that bortezomib functions as a radiosensitizer in colorectal cancer models. The purpose of this study was to determine the maximum tolerated dose (MTD) of bortezomib in combination with chemotherapy and radiation. Patients with locally advanced rectal adenocarcinomas, as staged by endoscopic ultrasound, were eligible. Bortezomib was administered on days 1, 4, 8, and 11 every 21 days for 2 cycles with 5-fluorouracil at 225 mg/m2/day continuously and 50.4 Gy of radiation. Dose escalation of bortezomib was conducted via a standard 3 + 3 dose escalation design. A subset of patients underwent serial tumor biopsies for correlative studies. Nine patients in 2 dose cohorts were enrolled. Diarrhea was the principal dose-limiting toxicity and occurred at the 1.0-mg/m2 dose level. There was no clear evidence of suppression of nuclear factor-kappaB target gene expression in biopsy samples. The MTD of bortezomib in combination with chemotherapy and radiation may be below a clinically relevant dose, limiting the clinical applicability of this combination. Performing biopsies before and during irradiation for determining gene expression in response to radiation therapy is feasible.