A molecular biology and phase II study of imetelstat (GRN163L) in children with recurrent or refractory central nervous system malignancies: a pediatric brain tumor consortium study

Telomerase activation is critical in many cancers including central nervous system (CNS) tumors. Imetelstat is an oligonucleotide that binds to the template region of the RNA component of telomerase, inhibiting its enzymatic activity. We conducted an investigator-sponsored molecular biology (MB) and phase II study to estimate inhibition of tumor telomerase activity and sustained responses by imetelstat in children with recurrent CNS malignancies. In the MB study, patients with recurrent medulloblastoma, high-grade glioma (HGG) or ependymoma undergoing resection received one dose of imetelstat as a 2-h intravenous infusion at 285 mg/m², 12–24 h before surgery. Telomerase activity was evaluated in fresh tumor from surgery. Post-surgery and in the phase II study, patients received imetelstat IV (days 1 and 8 q21-days) at 285 mg/m². Imetelstat pharmacokinetic and pharmacodynamic studies were performed. Of two evaluable patients on the MB trial, intratumoral telomerase activity was inhibited by 95?% compared to baseline archival tissue in one patient and was inevaluable in one patient. Forty-two patients (40 evaluable for toxicity) were enrolled: 9 medulloblastomas, 18 HGG, 4 ependymomas, 9 diffuse intrinsic pontine gliomas. Most common grade 3/4 toxicities included thrombocytopenia (32.5?%), lymphopenia (17.5?%), neutropenia (12.5?%), ALT (7.5?%) and AST (5?%) elevation. Two patients died of intratumoral hemorrhage secondary to thrombocytopenia leading to premature study closure. No objective responses were observed. Telomerase inhibition was observed in peripheral blood mononuclear cells (PBMCs) for at least 8 days. Imetelstat demonstrated intratumoral and PBMC target inhibition; the regimen proved too toxic in children with recurrent CNS tumors.     

A phase 1 and pharmacokinetic study of enzastaurin in pediatric patients with refractory primary central nervous system tumors: a pediatric brain tumor consortium study

BackgroundWe sought to estimate the maximum tolerated or recommended phase 2 dose and describe the pharmacokinetics and toxicities of enzastaurin, an oral inhibitor of protein kinase Cβ, in children with recurrent central nervous system malignancies.MethodsEnzastaurin was administered continuously once daily at 3 dose levels (260, 340, and 440 mg/m²) and twice daily at 440 mg/m²/day. Plasma pharmacokinetics were evaluated following a single dose and at steady state. Inhibition of protein kinase C and Akt cell signaling in peripheral blood mononuclear cells was evaluated. Akt pathway activity was measured in pretreatment tumor samples.ResultsThirty-three patients enrolled; 1 was ineligible, and 3 were nonevaluable secondary to early progressive disease. There were no dose-limiting toxicities during the dose-finding phase. Two participants receiving 440 mg/m² given twice daily experienced dose-limiting toxicities of grade 3 thrombocytopenia resulting in delayed start of course 2 and grade 3 alanine transaminase elevation that did not recover within 5 days. There were no grade 4 toxicities during treatment. The concentration of enzastaurin increased with increasing dose and with continuous dosing; however, there was not a significant difference at the 440 mg/m² dosing level when enzastaurin was administered once daily versus twice daily. There were no objective responses; however, 11 participants had stable disease >3 cycles, 7 with glioma, 2 with ependymoma, and 2 with brainstem glioma.ConclusionEnzastaurin was well tolerated in children with recurrent CNS malignancies, with chromaturia, fatigue, anemia, thrombocytopenia, and nausea being the most common toxicities. The recommended phase 2 dose is 440 mg/m²/day administered once daily.     

Phase I trial of VNP40101M (Cloretazine) in children with recurrent brain tumors: a pediatric brain tumor consortium study

PURPOSE: VNP40101M (Cloretazine), a novel DNA alkylating agent, was evaluated in a phase I study in children with recurrent brain tumors. EXPERIMENTAL DESIGN: VNP40101M was given i.v. daily for 5 consecutive days every 6 weeks for up to eight cycles. Dose escalation was done independently in patients stratified based on intensity of prior therapy (moderately pretreated, stratum I; heavily pretreated, stratum II). Correlative studies included pharmacokinetics and measurement of O(6)-alkylguanine-DNA alkyl transferase levels in peripheral blood mononuclear cells before and after treatment. RESULTS: Forty-one eligible patients (stratum I, 19; stratum II, 22) were enrolled on this study. The dose-limiting toxicity in 35 evaluable patients was myelosuppression, which occurred in 4 of 16 patients in stratum I and 3 of 19 patients in stratum II. Pharmacokinetic studies showed a median terminal half-life of 30 min (range, 14-39.5). The maximum tolerated dose in stratum I and II were 45 and 30 mg/m(2)/d daily for 5 days every 6 weeks, respectively. Peripheral blood mononuclear cells alkylguanine alkyl transferase levels did not decrease significantly after VNP40101M treatment. Central imaging review confirmed that three patients had stable disease for a median of 45 weeks (range, 37-61+) after therapy. CONCLUSIONS: The recommended dose of VNP40101M for phase II studies in children with brain tumors is 45 mg/m(2)/d in moderately pretreated and 30 mg/m(2)/d in heavily pretreated patients when administered for 5 consecutive days every 6 weeks.     

Phase II study of oxaliplatin in children with recurrent or refractory medulloblastoma, supratentorial primitive neuroectodermal tumors, and atypical teratoid rhabdoid tumors: a pediatric brain tumor consortium study

BACKGROUND: An open-label Phase II study of oxaliplatin was conducted to evaluate its safety and efficacy in children with recurrent or refractory medulloblastoma (MB), supratentorial primitive neuroectodermal tumors (SPNET), and atypical teratoid rhabdoid tumor (ATRT). METHODS: Patients were stratified as follows: stratum IA, first recurrence MB with measurable disease; IB, recurrent MB with only cerebral spinal fluid (CSF) positivity or linear leptomeningeal disease (LLD); IC, MB > or =second recurrence; stratum II, recurrent SPNET; stratum III, recurrent ATRT. Patients received oxaliplatin, 130 mg/m(2) intravenously over 2 hours every 3 weeks. The primary objective was to estimate the sustained response rate in stratum 1A. Plasma ultrafiltrate platinum pharmacokinetics were evaluated. RESULTS: A total of 43 patients with a median age of 8.5 years (range, 0.6-18.9 years) were enrolled. In stratum 1A, 2 of 15 had partial responses (PRs, 1 sustained PR). No responses were observed in other strata. The most frequent Grade 3 and 4 toxicities included thrombocytopenia (25.6%), neutropenia (16.3%), leukopenia (12%), increase in serum alanine transaminase (ALT) (7%), vomiting (4.7%), and sensory neuropathy (4.7%). No severe ototoxicity or nephrotoxicity was reported. Plasma ultrafiltrate platinum pharmacokinetic parameters were similar to adults, with a median clearance of 12.2 L/hr (range, 4.4-30 L/hr) and median area under the curve (AUC(0-infinity)) of 9.4 microg/mL/hr (range, 6.2-13.9 microg/mL/hr). CONCLUSIONS: Oxaliplatin was well tolerated in children but has limited activity in children with recurrent CNS embryonal tumors previously treated with platinum compounds.     

A phase II study of capecitabine and lapatinib in advanced refractory colorectal adenocarcinoma: A Wisconsin Oncology Network study

Background

Prognosis remains poor after progression on first-line chemotherapy for colorectal adenocarcinoma, and inactivation of the EGFR pathway with monoclonal antibodies is an effective treatment strategy in selected patients with metastatic disease. Lapatinib is an oral EGFR and HER-2 dual tyrosine kinase inhibitor that has not shown significant activity in metastatic colorectal cancer. However, lapatinib may act synergistically with capecitabine in anticancer effects.

Methods

This was an open-label, non-randomized phase II study of lapatinib 1,250 mg orally daily and capecitabine 2,000 mg/m² by mouth split into twice-daily dosing for 14 days of a 21 days cycle. Inclusion criteria included metastatic or locally advanced adenocarcinoma of the colon or rectum with progression by RECIST on or within six months of receiving a fluoridopyrimidine-, oxaliplatin- or irinotecan-containing regimen. Prior EGFR monoclonal antibody was permitted. K-ras testing was not routinely performed and was not a part of the study protocol.

Results

Twenty nine patients (16 M; 13 F) were enrolled in this study. There were no complete or partial responses. 41.4% of patients achieved stable disease as a best response. Median overall survival was 6.8 months, with a 1-year survival rate of 22%, and median progression-free survival was 2.1 months. The combination produced few grade 3 and no grade 4 toxicities. No grade 3 toxicity occurred in more than 10% of patients.

Conclusions

Although capecitabine and lapatinib is well tolerated, it is not an effective regimen in patients with refractory colorectal adenocarcinoma.Key Words: Colorectal cancer, capecitabine, lapatinib, EGFR, Her-2     

Vindesine in the treatment of refractory hematologic malignancies: A phase II study

A phase II evaluation of vindesine (VDS) was carried out in 46 patients with hematologic malignancies refractory to conventional chemotherapy. Two VDS schedules were employed (at random): (A) a weekly bolus (5 mg/m² i.v. × 4); (B) fractionated daily injections (0.5 mg/m² i.v. q. 12 h × 10, course to be repeated after 10–15 days). Complete and partial remissions were observed in acute lymphocytic leukemia ($\text{3}\text{14}$ patients), acute non-lymphocytic leukemia ($\text{2}\text{12}$ patients), chronic myelocytic leukemia in blastic crisis ($\text{4}\text{12}$ patients) and non-Hodgkin's lymphoma ($\text{4}\text{8}$ patients). Responses were seen with higher frequency in patients treated with the weekly bolus (42.8 vs 16%). Myelosuppression was the most relevant side effect in both schedules. Neurotoxicity occurred infrequently and was generally mild in degree. Further trials with VDS in combination with other drugs are recommended in hematologic malignancies.     

A phase 2 trial of verubulin for recurrent glioblastoma: a prospective study by the brain tumor investigational consortium (BTIC)

Treatment options are limited for recurrent glioblastoma (GBM). Verubulin is a microtubule destabilizer and vascular disrupting agent that achieve high brain concentration relative to plasma in animals. Adults with recurrent GBM who failed prior standard therapy were eligible. The primary endpoint was 1-month progression-free survival (PFS-1) for bevacizumab refractory (Group 2) and 6-month progression-free survival (PFS-6) for bevacizumab naïve patients (Group 1). Verubulin was administered at 3.3 mg/m² as a 2-h intravenous infusion once weekly for 3 consecutive weeks in a 4-week cycle. The planned sample size was 34 subjects per cohort. 56 patients (37 men, 19 women) were enrolled, 31 in Group 1 and 25 in Group 2. The PFS-6 for Group 1 was 14 % and the PFS-1 for Group 2 was 20 %. Median survival from onset of treatment was 9.5 months in Group 1 and 3.4 months in Group 2. Best overall response was partial response (n = 3; 10 % in Group 1; n = 1; 4.2 % in Group 2) and stable disease (n = 7; 23 % in Group 1; n = 5; 21 % in Group 2). In Group 1, 38.7 % of patients experienced a serious adverse event; however only 3.2 % were potentially attributable to study drug. In Group 2, 44 % of patients experienced a serious adverse event although none were attributable to study drug. Accrual was terminated early for futility. Single agent verubulin, in this dose and schedule, is well tolerated, associated with moderate but tolerable toxicity but has limited activity in either bevacizumab naïve or refractory recurrent GBM.     

A phase I study of panobinostat in pediatric patients with refractory solid tumors,including CNS tumors

Cancer Chemotherapy and Pharmacology - This was an open label, phase I (3?+?3 design), multi-centre study evaluating panobinostat in pediatric patients with refractory solid tumors....     

Supratentorial primitive neuroectodermal tumors: a Canadian pediatric brain tumor consortium report

Introduction Supratentorial primitive neuroectodermal tumors (SPNET) are rare tumors accounting for only 2.5% of childhood brain tumors. The purpose of this study was to describe the range of treatment regimens used to treat pediatric SPNET in Canada and to identify prognostic factors for overall survival in this population. Methods This study was a retrospective clinical analysis of SPNET patients treated over the last 10 years in Canada. A questionnaire was developed and distributed to all institutions in Canada who treat pediatric patients. Data were collected for patients <19 years of age who were diagnosed and treated for SPNET between 1995 and 2005. Results Data were obtained for 48 eligible patients. The stages of patients for whom complete data were provided were 80, 3, and 16% for metastatic stage M0, M1, and M2/3, respectively. The best responses to therapy included complete response in 44%, partial response in 8%, still on therapy in 2%, progressive disease in 31%, toxic death in 2%, and no therapy given in 12%. The 4-year survival was 37.7 ± 7.6%. The factors associated with an increase in survival were the use of radiation therapy and chemotherapy, and age >2 years. Overall survival was not affected by metastatic disease at diagnosis, tumor site, or degree of initial resection. Conclusions Survival is poor in SPNET patients but highest in those who received chemotherapy and radiation therapy. Further studies are needed to improve the survival of these patients.     

Survival of patients with newly diagnosed glioblastoma multiforme treated with RSR13 and radiotherapy: results of a phase II new approaches to brain tumor therapy CNS consortium safety and efficacy study.

PURPOSE: The objectives of this phase II study were to determine survival, safety, pharmacokinetics (PK), and pharmacodynamics (PD) of 2,4-[[(3,5-dimethylanilino)carbonyl]methyl]phenoxy]-2-methylpropionic acid (RSR13, efaproxiral) 100 mg/kg per day administered with standard cranial radiotherapy (RT) for the treatment of glioblastoma multiforme (GBM). RSR13, a synthetic allosteric modifier of hemoglobin, is a radiation-enhancing agent that noncovalently binds to hemoglobin, reduces oxygen-binding affinity, and increases oxygen unloading to hypoxic tissue. PATIENTS AND METHODS: Fifty patients with newly diagnosed GBM (Karnofsky performance status >or= 60) were enrolled onto this multicenter phase II study. Patients received daily RSR13 100 mg/kg intravenously infused for 30 minutes immediately before cranial RT (60 Gy in 30 fractions). Supplemental oxygen was given during RSR13 infusion and continued until after the RT treatment was completed. RT was given within 30 minutes of the end of RSR13 infusion. PK and PD determinations were performed. RESULTS: The median survival for the RSR13-treated patients was 12.3 months with 1-year and 18-month survival rates of 54% and 24%, respectively. Twenty-four percent of patients had greater than grade 2 toxicity, which was generally transient and self-limited. A significant PD effect on hemoglobin-oxygen binding affinity was demonstrated for most patients. CONCLUSION: RSR13 (100 mg/kg) administered immediately before cranial RT is well tolerated and is pharmacodynamically active. Median survival in excess of 1 year is favorable.     

A phase 1 Bayesian dose selection study of bortezomib and sunitinib in patients with refractory solid tumor malignancies

Background:

This phase 1 trial utilising a Bayesian continual reassessment method evaluated bortezomib and sunitinib to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), and recommended doses of the combination.

Methods:

Patients with advanced solid organ malignancies were enrolled and received bortezomib weekly with sunitinib daily for 4 weeks, every 6 weeks. Initial doses were sunitinib 25 mg and bortezomib 1 mg m⁻². Cohort size and dose level estimation was performed utilising the Escalation with Overdose Control (EWOC) adaptive method. Seven dose levels were evaluated; initially, sunitinib was increased to a goal dose of 50 mg with fixed bortezomib, then bortezomib was increased. Efficacy assessment occurred after each cycle using RECIST criteria.

Results:

Thirty patients were evaluable. During sunitinib escalation, DLTs of grade 4 thrombocytopenia (14%) and neutropenia (6%) at sunitinib 50 mg and bortezomib 1.3 mg m⁻² were seen. Subsequent experience showed tolerability and activity for sunitinib 37.5 mg and bortezomib 1.9 mg m⁻². Common grade 3/4 toxicities were neutropenia, thrombocytopenia, hypertension, and diarrhoea. The recommended doses for further study are bortezomib 1.9 mg m⁻² and sunitinib 37.5 mg. Four partial responses were seen. Stable disease >6 months was noted in an additional six patients.

Conclusion:

Bortezomib and sunitinib are well tolerated and have anticancer activity, particularly in thyroid cancer. A phase 2 study of this combination in thyroid cancer patients is planned.     

Phase I clinical trial of mafosfamide in infants and children aged 3 years or younger with newly diagnosed embryonal tumors: a pediatric brain tumor consortium study (PBTC-001).

PURPOSE: A phase I trial of intrathecal (IT) mafosfamide was performed to determine the optimal dose, dose-limiting toxicities, and incidence and severity of other toxicities when administered in association with concomitant multiagent systemic chemotherapy to children younger than 3 years with newly diagnosed embryonal tumors. PATIENTS AND METHODS: Twenty-five assessable patients received IT mafosfamide at one of six dose levels ranging from 5 mg to 17 mg. Patients were premedicated with dexamethasone (0.15 mg/kg) and morphine (0.1 mg/kg) before receiving IT mafosfamide. Serial samples of CSF for pharmacokinetic studies were obtained in a subset of patients with Ommaya reservoirs. RESULTS: Irritability, presumably secondary to pain or headache during mafosfamide administration, was dose limiting in two of three patients at the 17-mg dose level. The maximum-tolerated dose of IT mafosfamide following premedication with dexamethasone and morphine was 14 mg. CONCLUSION: The maximum tolerated dose and recommended phase II dose of IT mafosfamide in patients younger than 3 years with newly diagnosed embryonal CNS tumors is 14 mg. A trial to assess the efficacy of regional therapy with IT mafosfamide administered with intensive systemic chemotherapy in children younger than 3 years with primary intracranial embryonal tumors is now in progress.     

Phase-1 trial of gefitinib and temozolomide in patients with malignant glioma: a North American brain tumor consortium study

Purpose This is a phase-I study of gefitinib in combination with temozolomide in patients with gliomas. The goal of the study was to define the maximum tolerated dose (MTD) and to characterize the pharmacokinetics of gefitinib when combined with temozolomide. Patients and methods Patients were stratified according to co-administration of enzyme-inducing anti-epileptic drugs (EIAEDs). There were 26 evaluable patients enrolled (16 on EIAEDs, 10 not on EIAEDs). All but seven patients had Glioblastoma Multiforme (GBM), and only six cases had a Karnosfsky Performance Status (KPS) of less than 80; median age was 51 years. All had received prior radiotherapy and 14 patients had no prior chemotherapy. The starting dose of temozolomide was 150 mg/m²/day for 5 days every 28 days and could be escalated to a maximum dose of 200 mg/m²/day in subsequent cycles. The starting dose of gefitinib was 500 mg/day given by mouth on a continuous basis. Dose-limiting toxicity was assessed in cycle one only. Results For patients on EIAEDs, the MTD of gefitinib was 1,000 mg/day in combination with temozolomide. Dose-limiting toxicity (DLT) was due to diarrhea, nausea and vomiting. For patients not on EIAEDs, the MTD was 250 mg/day in combination with temozolomide. The DLT was due to increases in liver transaminases. Rash was not a significant toxicity at these dose levels. The peak concentration and AUC_0-24hr at the 500 mg dose level was 1.8 and 2.5-fold lower, respectively, in the EIAED group compared to the non-EIAED group; trough levels of gefitinib increased in both groups consistent with the reported terminal half-life ranging from 27 to 51 h. Conclusion The recommended phase-2 dose of gefitinib when used in combination with temozolomide is 1,000 and 250 mg/day, respectively, for patients on or not on EIAEDs.     

High-dose VP-16-213 monotherapy for refractory germinal malignancies: a phase II study

VP-16-213 at standard dose is one of the more active agents for the treatment of germ cell tumors. In previous phase I studies, VP-16-213 has been investigated in suprastandard dose when hematopoietic reconstitution was assured by autologous bone marrow transplantation (ABMT). This phase II study was performed to explore the possibility that an augmented dose of VP-16-213 may be more active than standard dose against germ cell tumors. Eleven patients with progressive refractory germ cell tumors were treated with high-dose VP-16-213: 2,400 mg/m2 with ABMT every three to four weeks followed by 1,200 mg/m2 without ABMT. Seven patients had received VP-16-213 at standard dose prior to high-dose VP-16-213. Toxicity to high-dose VP-16-213 included severe myelosuppression, nausea, vomiting, alopecia, mucositis, and hepatitis. Of 10 evaluable patients, two complete responses and four partial responses, all of short duration, were obtained. However, some patients unresponsive to standard-dose VP-16-213 exhibited responses to the augmented-dose VP-16-213. Therefore, although more myelosuppressive, VP-16-213 may have increased activity against germ cell tumors when administered at augmented dose. High-dose VP-16-213 may be considered in designing new approaches for initial management of patients with germ cell tumors not expected to be cured with standard chemotherapy.     

Phase II trial of PS-341 in patients with renal cell cancer: a University of Chicago phase II consortium study.

PURPOSE: Determine response rate, time to disease progression, and toxicity of the proteasome inhibitor PS-341 in patients with stage IV renal cell cancer. PATIENTS AND METHODS: PS-341 1.5 mg/m(2) was administered intravenously twice weekly for 2 weeks every 21 days. Dose escalation to 1.7 mg/m(2) ensued in the absence of grade 3 to 4 toxicities. Re-evaluation took place after three cycles. To assess proteasome inhibition, patients were randomly assigned to tumor core biopsy either before the first dose or after the third cycle of PS-341. Additionally, whole blood was collected at the same time intervals. RESULTS: Twenty-three patients were enrolled; 21 were assessable for response. Two patients were never treated (one patient refused treatment and one had insufficient tumor for biopsy). Eighteen patients completed at least three cycles of therapy; three patients experienced disease progression after two cycles. Grade 4 toxicities were arthralgia, diarrhea, and vomiting. Grade 3 toxicities included thrombocytopenia with one hemorrhage, anemia, febrile neutropenia, gastrointestinal toxicity, pain, fatigue, neuropathy (one sensory, one mixed sensorimotor), and electrolyte disturbances. Grade 1 to 2 neuropathy occurred in seven patients. One case of thrombosis and one case of pleural effusion occurred. Only one objective response was seen. Proteasome activity was measured by specific chymotryptic activity (SpA) and chymotryptic/tryptic activity (ChT:T). After PS-341, there was a decrease in mean whole blood SpA and ChT:T (P =.07 and.11, respectively). CONCLUSION: Evidence is lacking for clinically significant activity of PS-341 in metastatic renal cell cancer. Insufficient biopsy and whole blood sample numbers preclude conclusions regarding proteasome inhibition within tumor. Further evaluation in this disease setting is not recommended.     

A phase II study of lapatinib in patients with advanced biliary tree and hepatocellular cancer

Purpose  To evaluate the response to lapatinib, an inhibitor of epidermal growth factor receptors 1 and 2, in patients with advanced bilary tree cancer (BTC) and hepatocellular cancer (HCC). Methods  Lapatinib was dosed at 1,500 mg/day orally continuously. Results  Fifty-seven patients were accrued (BTC 17, HCC 40). Therapy was well tolerated. The response in BTC was 0% and in HCC was 5%. The progression free survival (PFS) for BTC and HCC patients was 1.8 (95% CI: 1.7–5.2) months and 2.3 (95% CI: 1.7–5.6) months. The median survival for BTC and HCC patients was 5.2 (95% CI 3.3–∞) months and 6.2 (95% CI: 5.1–∞) months. EGFR genotyping indicated HCC patients with <20 repeats have the lowest PFS. The occurrence of any skin rash significantly prolonged PFS and survival. Conclusions  Lapatinib was well-tolerated. There was evidence of activity in HCC, but therapy with lapatinib did not meet the predefined efficacy rate.     

A multicenter phase II trial of intrathecal topotecan in patients with meningeal malignancies

To determine the therapeutic efficacy (13-week and 26-week CNS progression-free survival [PFS], response rate, and overall survival) and safety of intraventricular (IVent) topotecan in patients with neoplastic meningitis (NM), we conducted a phase II, open-label, nonrandomized, single-arm trial of IVent topotecan in patients with NM using 400 mug of topotecan IVent twice weekly for 6 weeks, followed by evaluation with imaging, cerebrospinal fluid (CSF), and physical examinations. In the absence of disease progression, patients were then treated with IVent topotecan weekly for 6 weeks, twice monthly for 4 months, and monthly thereafter. Sixty-two patients (23 males and 39 females) were enrolled from April 2001 through March 2006. Median age and KPS at enrollment were 56 (range 5-83) and 80 (range 60-100), respectively. Primary cancers included breast (19), lung (13), CNS (14), and others (16). Forty patients (65%) completed the 6-week induction period, among whom 13 (21%) had CSF clearance of malignant cells. Kaplan-Meier estimates of PFS at 13 and 26 weeks were 30% (95% confidence interval [CI], 20%-45%) and 19% (95% CI, 11%-34%). Overall median survival (50 deaths) was 15 weeks (95% CI, 13-24 weeks). The most common side effect was chemical meningitis in 32% of patients (5% grade 3); 32% experienced no drug side effects. IVent topotecan is well tolerated, but provides no added benefit over other IVent therapies. Because of its modest side effect profile, combining IVent topotecan with other IVent or systemic interventions should be considered.