Active oral regimen for elderly adults with newly diagnosed acute myelogenous leukemia: a preclinical and phase 1 trial of the farnesyltransferase inhibitor tipifarnib (R115777, Zarnestra) combined with etoposide.
ABSTRACT: The farnesyltransferase inhibitor tipifarnib exhibits modest activity against acute myelogenous leukemia. To build on these results, we examined the effect of combining tipifarnib with other agents. Tipifarnib inhibited signaling downstream of the farnesylated small G protein Rheb and synergistically enhanced etoposide-induced antiproliferative effects in lymphohematopoietic cell lines and acute myelogenous leukemia isolates. We subsequently conducted a phase 1 trial of tipifarnib plus etoposide in adults over 70 years of age who were not candidates for conventional therapy. A total of 84 patients (median age, 77 years) received 224 cycles of oral tipifarnib (300-600 mg twice daily for 14 or 21 days) plus oral etoposide (100-200 mg daily on days 1-3 and 8-10). Dose-limiting toxicities occurred with 21-day tipifarnib. Complete remissions were achieved in 16 of 54 (30%) receiving 14-day tipifarnib versus 5 of 30 (17%) receiving 21-day tipifarnib. Complete remissions occurred in 50% of two 14-day tipifarnib cohorts: 3A (tipifarnib 600, etoposide 100) and 8A (tipifarnib 400, etoposide 200). In vivo, tipifarnib plus etoposide decreased ribosomal S6 protein phosphorylation and increased histone H2AX phosphorylation and apoptosis. Tipifarnib plus etoposide is a promising orally bioavailable regimen that warrants further evaluation in elderly adults who are not candidates for conventional induction chemotherapy. These clinical studies are registered at www.clinicaltrials.gov as #NCT00112853.
Project description:Tipifarnib (T) exhibits modest activity in elderly adults with newly diagnosed acute myelogenous leukemia (AML). Based on preclinical synergy, a phase 1 trial of T plus etoposide (E) yielded 25% complete remission (CR). We selected 2 comparable dose levels for a randomized phase 2 trial in 84 adults (age range, 70-90 years; median, 76 years) who were not candidates for conventional chemotherapy. Arm A (T 600 mg twice a day × 14 days, E 100 mg days 1-3 and 8-10) and arm B (T 400 mg twice a day × 14 days, E 200 mg days 1-3 and 8-10) yielded similar CR, but arm B had greater toxicity. Total CR was 25%, day 30 death rate 7%. A 2-gene signature of high RASGRP1 and low aprataxin (APTX) expression previously predicted for T response. Assays using blasts from a subset of 40 patients treated with T plus E on this study showed that AMLs with a RASGRP1/APTX ratio of more than 5.2 had a 78% CR rate and negative predictive value 87%. This ratio did not correlate with outcome in 41 patients treated with conventional chemotherapies. The next T-based clinical trials will test the ability of the 2-gene signature to enrich for T responders prospectively. This study is registered at www.clinicaltrials.gov as #NCT00602771.
Project description:The aims of this study were to determine the maximum-tolerated dose (MTD), toxicity profile, and pharmacokinetics of irinotecan given with oral R115777 (tipifarnib), a farnesyl protein transferase inhibitor. Patients were treated with escalating doses of irinotecan with interval-modulated dosing of R115777 (continuously or on days 1-14, and repeated every 21 days). In total, 35 patients were entered onto the trial for a median duration of treatment of 43 days (range, 5-224 days). Neutropenia and thrombocytopenia were the dose-limiting toxicities; other side effects were mostly mild. The MTD was established at R115777 300 mg b.i.d. for 14 consecutive days with irinotecan 350 mg x m(-2) given every 3 weeks starting on day 1. Three patients had a partial response and 14 had stable disease. In the continuous schedule, the area under the curves of irinotecan and its active metabolite SN-38 were 20.0% (P=0.004) and 38.0% (P<0.001) increased by R115777, respectively. Intermittent dosing of R115777 at a dose of 300 mg b.i.d. for 14 days every 3 weeks is the recommended dose of R115777 in combination with the recommended single-agent irinotecan dose of 350 mg x m(-2).
Project description:Background Sorafenib is a multi-kinase inhibitor with activity against fms-like tyrosine kinase 3 with internal tandem duplication mutation and Raf kinase among others. A phase I dose escalation study of sorafenib was conducted in patients with advanced myelodysplastic syndrome and relapsed or refractory acute leukemias.Fifty patients received one of two different schedules; Schedule "A": once or twice daily, five days per week, every week for a 21 day cycle, and Schedule "B": once or twice daily, for 14 days every 21 days. Dose limiting toxicities were grade 3/4 hypertension, hyperbilirubinemia, and amylase elevation. The recommended phase II dose in hematologic malignancies is 400 mg twice daily for both schedules.Complete remissions or complete remissions with incomplete recovery of platelets were achieved in 5 (10%) patients (all with fms-like tyrosine kinase 3-internal tandem duplication). Significant reduction in bone marrow and/or peripheral blood blasts was seen in an additional 17 (34%) patients (all with fms-like tyrosine kinase 3-internal tandem duplication). Eleven of these responses (including 3 complete remissions/complete remissions with incomplete recovery) lasted for 2 cycles or beyond. In conclusion, sorafenib is active and well tolerated in acute myelogenous leukemia with fms-like tyrosine kinase 3 internal tandem duplication mutation. Conclusions Additional studies of sorafenib in patients with acute myelogenous leukemia, particularly those with fms-like tyrosine kinase 3 internal tandem duplication, are warranted, including sorafenib-based combinations. (ClinicalTrials.gov Identifier: NCT00217646).
Project description:A phase 2 study of the oral farnesyltransferase inhibitor tipifarnib was conducted in 93 adult patients with relapsed or refractory lymphoma. Patients received tipifarnib 300 mg twice daily on days 1-21 of each 28-day cycle. The median number of prior therapies was 5 (range, 1-17). For the aggressive B-cell, indolent B-cell, and T-cell and Hodgkin lymphoma (HL/T) groups, the response rates were 17% (7/42), 7% (1/15), and 31% (11/36), respectively. Of the 19 responders, 7 were diffuse large B-cell non-Hodgkin lymphoma (NHL), 7 T-cell NHL, 1 follicular grade 2, and 4 HL. The median response duration for the 19 responders was 7.2 months (mean, 15.8 months; range, 1.8-62), and 5 patients in the HL/T group are still receiving treatment at 29-64+ months. The grade 3/4 toxicities observed were fatigue and reversible myelosuppression. Correlative studies suggest that Bim and Bcl-2 should be examined as potential predictors of response in future studies. These results indicate that tipifarnib has activity in lymphoma, particularly in heavily pretreated HL/T types, with little activity in follicular NHL. In view of its excellent toxicity profile and novel mechanism of action, further studies in combination with other agents appear warranted. This trial is registered at www.clinicaltrials.gov as #NCT00082888.
Project description:Although farnesyltransferase inhibitors have shown promising activity in relapsed lymphoma and sporadic activity in acute myelogenous leukemia, their mechanism of cytotoxicity is incompletely understood, making development of predictive biomarkers difficult. In the present study, we examined the action of tipifarnib in human acute myelogenous leukemia cell lines and clinical samples. In contrast to the Ras/MEK/ERK pathway-mediated Bim upregulation that is responsible for tipifarnib-induced killing of malignant lymphoid cells, inhibition of Rheb-induced mTOR signaling followed by dose-dependent upregulation of Bax and Puma occurred in acute myelogenous leukemia cell lines undergoing tipifarnib-induced apoptosis. Similar Bax and Puma upregulation occurred in serial bone marrow samples harvested from a subset of acute myelogenous leukemia patients during tipifarnib treatment. Expression of FTI-resistant Rheb M184L, like knockdown of Bax or Puma, diminished tipifarnib-induced killing. Further analysis demonstrated that increased Bax and Puma levels reflect protein stabilization rather than increased gene expression. In U937 cells selected for tipifarnib resistance, neither inhibition of signaling downstream of Rheb nor Bax and Puma stabilization occurred. Collectively, these results not only identify a pathway downstream from Rheb that contributes to tipifarnib cytotoxicity in human acute myelogenous leukemia cells, but also demonstrate that FTI-induced killing of lymphoid versus myeloid cells reflects distinct biochemical mechanisms downstream of different farnesylated substrates. (ClinicalTrials.gov identifier NCT00602771).
Project description:We report on 348 patients ? 70 years (median age 78 years) with acute myeloid leukemia (>50% with secondary AML) randomized to receive either 600 mg or 300 mg of tipifarnib orally twice daily on days 1-21 or days 1-7 and 15-21, repeated every 28 days (4 treatment regimens). Responses were seen in all regimens, with overall response rate (CR + CRi + PR) highest (20%) among patients receiving tipifarnib 300 mg twice daily on days 1-21. Toxicities were acceptable. Unless predictors of response to tipifarnib are identified, further study as a single agent in this population is unwarranted.
Project description:BACKGROUND:Fulvestrant produces a clinical benefit rate (CBR) of approximately 45% in tamoxifen-resistant, hormone receptor (HR)-positive metastatic breast cancer (MBC) and 32% in aromatase inhibitor (AI)-resistant disease. The farnesyltransferase inhibitor tipifarnib inhibits Ras signaling and has preclinical and clinical activity in endocrine therapy-resistant disease. The objective of this study was to determine the efficacy and safety of tipifarnib-fulvestrant combination in HR-positive MBC. PATIENTS AND METHODS:Postmenopausal women with no prior chemotherapy for metastatic disease received i.m. fulvestrant 250 mg on day 1 plus oral tipifarnib 300 mg twice daily on days 1-21 every 28 days. The primary end point was CBR. RESULTS:The CBR was 51.6% [95% confidence interval (CI) 34.0% to 69.2%] in 31 eligible patients and 47.6% (95% CI 26.3% to 69.0%) in 21 patients with AI-resistant disease. A futility analysis indicated that it was unlikely to achieve the prespecified 70% CBR. Tipifarnib dose modification was required in 8 of 33 treated patients (24%). CONCLUSIONS:The target CBR of 70% for the tipifarnib-fulvestrant combination in HR-positive MBC was set too high and was not achieved. The 48% CBR in AI-resistant disease compares favorably with the 32% CBR observed with fulvestrant alone in prior studies and merit further clinical and translational evaluation.
Project description:To determine the maximum-tolerated dose (MTD) of the histone deacetylase inhibitor vorinostat combined with fixed doses of cytarabine (ara-C or cytosine arabinoside) and etoposide in patients with poor-risk or advanced acute leukemia, to obtain preliminary efficacy data, describe pharmacokinetics, and in vivo pharmacodynamic effects of vorinostat in leukemia blasts.In this open-label phase I study, vorinostat was given orally on days one to seven at three escalating dose levels: 200 mg twice a day, 200 mg three times a day, and 300 mg twice a day. On days 11 to 14, etoposide (100 mg/m(2)) and cytarabine (1 or 2 g/m(2) twice a day if ?65 or <65 years old, respectively) were given. The study used a standard 3+3 dose escalation design.Eighteen of 21 patients with acute myelogenous leukemia (AML) treated on study completed planned therapy. Dose-limiting toxicities [hyperbilirubinemia/septic death (1) and anorexia/fatigue (1)] were encountered at the 200 mg three times a day level; thus, the MTD was established to be vorinostat 200 mg twice a day. Of 21 patients enrolled, seven attained a complete remission (CR) or CR with incomplete platelet recovery, including six of 13 patients treated at the MTD. The median remission duration was seven months. No differences in percentage S-phase cells or multidrug resistance transporter (MDR1 or BCRP) expression or function were observed in vivo in leukemia blasts upon vorinostat treatment.Vorinostat 200 mg twice a day can be given safely for seven days before treatment with cytarabine and etoposide. The relatively high CR rate seen at the MTD in this poor-risk group of patients with AML warrants further studies to confirm these findings.
Project description:BACKGROUND:This exploratory single-arm phase II study evaluated the efficacy and safety of RRx-001 followed by reintroduction of platinum plus etoposide in patients with previously treated small-cell lung cancer (SCLC). METHODS:Patients were treated with RRx-001 4?mg IV on day 1 of each week of a 21-day cycle followed at progression by re-challenge with etoposide 80-100 IV mg/m2 on days 1, 2 and 3 and cisplatin 60-80?mg/m2 IV on day 1 or carboplatin AUC 5-6 IV on day 1, every 21 days. The primary end points were overall survival (OS) and overall response rate to platinum regimen. RESULTS:Twenty-six patients were enroled and received at least one dose of RRx-001. The median number of prior lines of therapy was 2 (range 1-9) and 19 (73.1%) patients had platinum-resistant disease. In the intention-to-treat population, one patient (3.8%) had complete response and six (23.1%) had partial response on platinum plus etoposide. The estimated median and 12-month OS from enrolment were 8.6 months and 44.1%, respectively. The most common treatment-emergent adverse event from RRx-001 was mild discomfort at the infusion site (23%). CONCLUSIONS:RRx-001 followed by re-challenge with platinum plus etoposide chemotherapy is feasible and associated with promising results. CLINICAL TRIAL REGISTRATION:NCT02489903.
Project description:Capecitabine produces an objective response rate of up to 25% in anthracycline-treated, taxane-resistant metastatic breast cancer (MBC). The farnesyltransferase inhibitor tipifarnib inhibits Ras signaling and has clinical activity when used alone in MBC. The objective of this study was to determine the efficacy and safety of tipifarnib-capecitabine combination in MBC patients who were previously treated with an anthracycline and progressed on taxane therapy. Eligible patients received oral capecitabine 1,000 mg/m2 twice daily plus oral tipifarnib 300 mg twice daily on days 1-14 every 21 days. The primary endpoint was ORR. The trial was powered to detect an improvement in response rate from 25 to 40%. Among 63 eligible, partial response occurred in six patients (9.5%; 90% CI 4.2-17.9%), median progression-free survival was 2.6 months (95% CI 2.1-4.4), and median overall survival was 11.4 months (95% CI 7.7-14.0). Dose modifications were required for 43 patients (68%) for either tipifarnib and/or capecitabine. Grades 3 and 4 toxicities were seen in 30 patients (44%; 90% CI 44.4-67.0%) and 11 patients (16%; 90% CI 10.8-29.0%), respectively. The most common grade 3 toxicities included neutropenia, nausea, and vomiting; and the most common grade 4 toxicity was neutropenia (8 out of 11 cases). The tipifarnib-capecitabine combination is not more effective than capecitabine alone in MBC patients who were previously treated with an anthracycline and taxane therapy.