Plasma pharmacokinetics and pharmacodynamics of a new prodrug N-l-leucyldoxorubicin and its metabolites in a phase I clinical trial.

PURPOSE N-l-leucyldoxorubicin (Leu-Dox) was developed as a prodrug of doxorubicin (Dox) to circumvent the cardiotoxicity associated with repeated administration of Dox. Our purpose was to assess the pharmacokinetics of Leu-Dox, Dox, doxorubicinol (Dol) and four other metabolites for pharmacokinetically guided dose-escalation and to verify the prodrug character of Leu-Dox. PATIENTS AND METHODS Blood and urine of 14 patients were sampled during the phase I clinical trial and analyzed by high-performance liquid chromatography. Dose levels of Leu-Dox ranged from 18 mg/m2 to 225 mg/m2, the maximum-tolerated dose (MTD). Hematologic parameters were monitored regularly in each patient. RESULTS Leu-Dox was rapidly distributed (half-life at alpha phase [t1/2 alpha] = 2.5 +/- 0.6 minutes) followed by a biphasic elimination (half-life at beta phase [t1/2 beta] = 17.4 +/- 7.3 minutes; half-life at gamma phase [t1/2 gamma] = 1.5 +/- 0.5 hours), as measured over the first 12 hours after administration. In three patients, in whom Leu-Dox was found in the plasma for up to 48 hours after injection, a final elimination half-life (t1/2,elim) of 16 hours was observed. The t1/2,elim of Leu-Dox was short (0.6 to 16.5 hours) compared with the t1/2,elim of Dox (38 +/- 11 hours). The mean residence time and apparent volume of distribution were 23 +/- 5 minutes and 19 +/- 6 L/m2, respectively. Only 1.5% to 5% of the dose was excreted in the urine over 48 hours, with Dox as major constituent. Dox was rapidly formed, reaching its maximum concentration within 10 minutes after the end of Leu-Dox infusion. Areas under the plasma concentration versus time curve (AUC infinity, mean +/- SD, n = 16) of Leu-Dox, Dox, and Dol were 115 +/- 27 mumol.min/L, 41 +/- 12 mumol.min/L, and 33 +/- 14 mumol.min/L after a dose of 60 mg/m2 Leu-Dox (= 86 mumol/m2). After the same molar dose of Dox (50 mg/m2 = 86 mumol/m2), the AUC infinity of Dox was 179 mumol.min/L, indicating that Leu-Dox was converted into Dox for 23% in the plasma compartment. The AUCs infinity of Leu-Dox, Dox, and Dol increased linearly with the dose. Negligible AUCs were observed for the other four metabolites. The AUCs infinity of Leu-Dox and Dox at the MTD (517 and 145 mumol.min/L, respectively) were lower than those in mice at the LD10 (1,930 and 798 mumol.min/L, respectively), which means that the MTD could not be predicted from the preclinical pharmacokinetics in mice. Hematologic toxicity, especially the WBC count, appeared to correlate much better with the AUC of Dox (r = .91) than with the AUC of Leu-Dox (r = .74), thus confirming the prodrug character of Leu-Dox. CONCLUSIONS Dox is rapidly formed from Leu-Dox, and seems causative in the observed myelotoxicity. The MTD could not be predicted from the AUC at the LD10 in mice.

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Phase I Trial of Carmustine Plus O6-Benzylguanine for Patients With Recurrent or Progressive Malignant Glioma

Journal of Clinical Oncology ◽

10.1200/jco.2000.18.20.3522 ◽

2000 ◽

Vol 18 (20) ◽

pp. 3522-3528 ◽

Cited By ~ 95

Author(s):

Henry S. Friedman ◽

James Pluda ◽

Jennifer A. Quinn ◽

Reginald B. Ewesuedo ◽

Lina Long ◽

...

Keyword(s):

Phase I ◽

Malignant Glioma ◽

Half Life ◽

Phase I Trial ◽

Maximum Tolerated Dose ◽

Time Curve ◽

Elimination Half Life ◽

Major Mechanism ◽

Elimination Half ◽

The Mean

PURPOSE: The major mechanism of resistance to alkylnitrosourea therapy involves the DNA repair protein O6-alkylguanine-DNA alkyltransferase (AGT), which removes chloroethylation or methylation damage from the O6 position of guanine. O6-benzylguanine (O6-BG) is an AGT substrate that inhibits AGT by suicide inactivation. We conducted a phase I trial of carmustine (BCNU) plus O6-BG to define the toxicity and maximum-tolerated dose (MTD) of BCNU in conjunction with the preadministration of O6-BG with recurrent or progressive malignant glioma. PATIENTS AND METHODS: Patients were treated with O6-BG at a dose of 100 mg/m2 followed 1 hour later by BCNU. Cohorts of three to six patients were treated with escalating doses of BCNU, and patients were observed for at least 6 weeks before being considered assessable for toxicity. Plasma samples were collected and analyzed for O6-BG, 8-oxo-O6-BG, and 8-oxoguanine concentration. RESULTS: Twenty-three patients were treated (22 with glioblastoma multiforme and one with anaplastic astrocytoma). Four dose levels of BCNU (13.5, 27, 40, and 55 mg/m2) were evaluated, with the highest dose level being complicated by grade 3 or 4 thrombocytopenia and neutropenia. O6-BG rapidly disappeared from plasma (elimination half-life = 0.54 ± 0.14 hours) and was converted to a longer-lived metabolite, 8-oxo-O6-BG (elimination half-life = 5.6 ± 2.7 hours) and further to 8-oxoguanine. There was no detectable O6-BG 5 hours after the start of the O6-BG infusion; however, 8-oxo-O6-BG and 8-oxoguanine concentrations were detected 25 hours after O6-BG infusion. The mean area under the concentration-time curve (AUC) of 8-oxo-O6-BG was 17.5 times greater than the mean AUC for O6-BG. CONCLUSION: These results indicate that the MTD of BCNU when given in combination with O6-BG at a dose of 100 mg/m2 is 40 mg/m2 administered at 6-week intervals. This study provides the foundation for a phase II trial of O6-BG plus BCNU in nitrosourea-resistant malignant glioma.

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Phase I and Correlative Biology Study of Cilengitide in Patients With Recurrent Malignant Glioma

Journal of Clinical Oncology ◽

10.1200/jco.2006.06.6514 ◽

2007 ◽

Vol 25 (13) ◽

pp. 1651-1657 ◽

Cited By ~ 214

Author(s):

L. Burt Nabors ◽

Tom Mikkelsen ◽

Steven S. Rosenfeld ◽

Fred Hochberg ◽

Narasimha S. Akella ◽

...

Keyword(s):

Phase I ◽

Malignant Glioma ◽

Complete Response ◽

Maximum Tolerated Dose ◽

Toxicity Assessment ◽

Perfusion Magnetic Resonance Imaging ◽

Hematologic Toxicity ◽

Recurrent Malignant Glioma ◽

Time Curve ◽

Magnetic Resonance Imaging Mri

Purpose This multi-institutional phase I trial was designed to determine the maximum-tolerated dose (MTD) of cilengitide (EMD 121974) and to evaluate the use of perfusion magnetic resonance imaging (MRI) in patients with recurrent malignant glioma. Patients and Methods Patients received cilengitide twice weekly on a continuous basis. A treatment cycle was defined as 4 weeks. Treatment-related dose-limiting toxicity (DLT) was defined as any grade 3 or 4 nonhematologic toxicity or grade 4 hematologic toxicity of any duration. Results A total of 51 patients were enrolled in cohorts of six patients to doses of 120, 240, 360, 480, 600, 1,200, 1,800, and 2,400 mg/m2 administered as a twice weekly intravenous infusion. Three patients progressed early and were inevaluable for toxicity assessment. The DLTs observed were one thrombosis (120 mg/m2), one grade 4 joint and bone pain (480 mg/m2), one thrombocytopenia (600 mg/m2) and one anorexia, hypoglycemia, and hyponatremia (800 mg/m2). The MTD was not reached. Two patients demonstrated complete response, three patients had partial response, and four patients had stable disease. Perfusion MRI revealed a significant relationship between the change in tumor relative cerebral blood flow (rCBF) from baseline and area under the plasma concentration versus time curve after 16 weeks of therapy. Conclusion Cilengitide is well tolerated to doses of 2,400 mg/m2, durable complete and partial responses were seen in this phase I study, and clinical response appears related to rCBF changes.

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Phase I clinical and pharmacokinetic trial of penclomedine using a novel, two-stage trial design for patients with advanced malignancy.

Journal of Clinical Oncology ◽

10.1200/jco.1998.16.3.1142 ◽

1998 ◽

Vol 16 (3) ◽

pp. 1142-1149 ◽

Cited By ~ 9

Author(s):

J Berlin ◽

J A Stewart ◽

B Storer ◽

K D Tutsch ◽

R Z Arzoomanian ◽

...

Keyword(s):

Phase I ◽

Trial Design ◽

Fibonacci Sequence ◽

Maximum Tolerated Dose ◽

Hematologic Toxicity ◽

Two Stage ◽

Eligibility Criteria ◽

Stage Design ◽

Advanced Malignancy ◽

Elimination Half

PURPOSE A novel phase I trial design was used to determine the maximum-tolerated dose (MTD) and pharmacokinetics for penclomedine when administered as an intravenous (i.v.) infusion over 1 hour daily for 5 days, repeated every 28 days. This study also tests the feasibility of a novel two-stage design for phase I trials. PATIENTS AND METHODS Twenty-eight patients with advanced malignancy who met standard eligibility criteria were treated with i.v. penclomedine. The initial daily dose was 50 mg/m2. Dose escalations were planned using a modified Fibonacci sequence. One patient was enrolled on each dose level during the first stage of this trial. In the second stage, patients were enrolled in cohorts of three, proceeding in an up-and-down manner based on toxicities observed. MTD was determined by logistic regression analysis. Pharmacokinetic assessment was performed during the first cycle of treatment. RESULTS Dose-limiting toxicities (DLT) observed during this trial were principally neurologic and were self-limited. Although hematologic toxicity was rare, the few patients with significant hematologic changes experienced late nadirs with prolonged time to recovery. The MTD was estimated as 381 mg/m2 (80% CI, 343 to 415 mg/m2). Although there was a long elimination half-life, accumulation of penclomedine over the 5 days of administration was negligible. CONCLUSION The novel trial design used in this study was safe and appeared effective in limiting the numbers of patients treated at lower-dose levels. Reversible neurotoxicity was dose-limiting. Although the estimated MTD was 381 mg/m2, any dose within the CI would be reasonable for phase II study.

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A phase I clinical trial of vorinostat in combination with sFULV2 in patients with refractory solid tumors

Journal of Clinical Oncology ◽

10.1200/jco.2009.27.15_suppl.4083 ◽

2009 ◽

Vol 27 (15_suppl) ◽

pp. 4083-4083

Author(s):

M. G. Fakih ◽

L. Pendyala ◽

M. J. Egorin ◽

G. Fetterly ◽

I. Espinoza-Delgado ◽

...

Keyword(s):

Clinical Trial ◽

Antitumor Activity ◽

Phase I ◽

Solid Tumors ◽

Maximum Tolerated Dose ◽

Phase I Clinical Trial ◽

Fixed Dose ◽

Over Expression ◽

Dose Dependent Fashion ◽

Grade 3

4083 Background: Thymidylate synthase (TS) over-expression is associated with 5-FU resistance. Pre-clinical studies demonstrate that vorinostat down-regulates intra-tumor TS in a dose-dependent fashion and augments 5-FU antitumor activity in xenograft models. We conducted a phase I clinical trial of an intermittent schedule of QD x 3 vorinostat in combination with a fixed dose of fluorouracil (5-FU) and leucovorin (LV) in patients (pts) with refractory solid tumors. Methods: Vorinostat was escalated in a standard 3 x 3 design in combination with a fixed dose of 5-FU and LV (simplified de Gramont regimen, sFULV2). Vorinostat was given QD x 3 on an every-2-week cycle. sFULV2 started on day 2 of vorinostat and consisted of leucovorin 400 mg/m2 i.v. over 2 hrs followed by 5-FU 400 mg/m2 bolus and 5-FU 2400 mg/m2 over 46 hrs. Results: 24 pts were enrolled: Male/Female: 11/13; ECOG 0/1: 6/18; Age: median 60 (range 42–77) yrs. 21 pts had colorectal cancer (CRC), 1 had gastric, 1 had esophageal, and 1 had anal cancer. Vorinostat dose-levels (DL) were 600 mg, 800 mg, 1000 mg, 1200 mg, 1400 mg, 1700 mg, and 2000 mg. Dose-limiting toxicities (DLT), consisting of fatigue and hand-and-foot syndrome (H&F), were seen in 2 of 3 pts at the 2000 mg DL. None of the 6 pts at the 1700 mg DL had a DLT. Cycle 1 grade 3/4 toxicities consisted of thrombocytopenia, GI bleeding, fatigue, and H&F in 2 pts at the 2000 mg DL and a non-DLT G3 diarrhea (lasted <24 hrs) in 1 pt at the 1700 mg DL. Grade 2 nausea, fatigue, and anorexia were common; especially at DL ≥ 1700 mg. Antitumor activity was noted in pts with CRC despite prior refractoriness to 5-FU and failure to oxaliplatin, irinotecan, and cetuximab in all pts. 12/21 CRC pts had a confirmed SD (11) or PR (1). CRC pts had a median PFS of 4 months, a ≥ 6 months PFS rate of 43%, and a ≥ 8 months PFS rate of 33%. Conclusions: The maximum tolerated dose (MTD) of vorinostat in combination with sFULV2 is 1700 mg PO QD x 3 every 2 weeks. This combination is associated with considerable activity in pts with 5-FU-refractory CRC and warrants further investigation. An expanded MTD cohort is accruing to investigate 5-FU-vorinostat PK interaction and intra-tumor TS down-regulation. (This work was supported by a grant from CTEP and the ACS.) No significant financial relationships to disclose.

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Phase I Clinical Trial of Oral Administration of the Histone Deacetylase (HDAC) Inhibitor Suberoylanilide Hydroxamic Acid (SAHA) in Patients with Relapsed/Refractory Multiple Myeloma (MM).

Blood ◽

10.1182/blood.v104.11.1503.1503 ◽

2004 ◽

Vol 104 (11) ◽

pp. 1503-1503 ◽

Cited By ~ 8

Author(s):

Paul Richardson ◽

Robert L. Schlossman ◽

Constantine S. Mitsiades ◽

Nikhil C. Munshi ◽

Kathleen Colson ◽

...

Keyword(s):

Clinical Trial ◽

Multiple Myeloma ◽

Phase I ◽

Dose Level ◽

Hdac Inhibitor ◽

Hydroxamic Acid ◽

Phase I Clinical Trial ◽

Hematologic Toxicity ◽

Suberoylanilide Hydroxamic Acid ◽

Grade 3

Abstract Introduction: Histone deacetylases (HDACs) affect cell growth at the transcriptional level by regulating the acetylation status of nucleosomal histones, and HDAC inhibition induces differentiation and/or apoptosis in transformed cells. We have recently shown that HDAC inhibitors, such as suberoylanilide hydroxamic acid (SAHA), induce apoptosis of human multiple myeloma (MM) cells via a constellation of antiproliferative and/or proapoptotic molecular events, including decreased expression of multiple signaling molecules and oncogenes implicated in MM pathophysiology. Based on these promising pre-clinical data, we embarked on a phase I clinical trial of oral SAHA in patients with advanced MM. Methods: An open-label phase I dose-escalation of oral SAHA (200, 250 and 300 mg po bid for 5 consecutive days followed by 2 days of rest) was administered in 4-week cycles in pts with relapsed/refractory MM. The primary objective was to determine the maximum tolerated dose (MTD), and secondary objectives included evaluation of tumor response, as well as assessment of markers of biologic activity in peripheral blood mononuclear cells and bone marrow plasma cells. Dose limiting toxicity (DLT) was defined as grade 4 or greater hematologic toxicity and/or grade 3 or greater non-hematologic toxicity within the first 28 days of treatment. Results: To date, 8 pts with advanced MM (5 relapsed and 3 with relapsed, refractory MM) have been enrolled at the first 2 dose levels, receiving a median of 3 cycles (range 2–9) of therapy. In 7 evaluable pts, one pt at the 2nd dose level (250 mg po bid) developed DLT with grade 3 fatigue, prompting dose reduction with the next cycle. Other side effects have included grade 2 fatigue (3 pts), grade 2 diarrhea (2 pts), grade 2 indigestion (2 pts) and grade 2 dehydration (2 pts), which have been manageable with appropriate supportive care. In one patient, during cycle 4 at dose level 2, grade 3 dehydration occurred with associated metabolic abnormalities that readily resolved with electrolyte supplementation and rehydration. The patient has continued on therapy at reduced dose (250 mg po bid, 4 days on, 3 days off) without recurrence of this toxicity. Importantly, no significant myelosuppression, neuropathy or sedation, which are associated with other anti-MM agents, has been seen. In 7 evaluable pts: minor responses (MR) were documented in 2 patients (25–50% reduction in serum paraprotein levels); stable disease (SD: less than 25% reduction in paraprotein levels) was observed in 2 pts; and progressive disease (PD) was documented in 3 pts. Conclusion: SAHA is an orally administered HDAC inhibitor with manageable toxicity and preliminary evidence of antitumor activity in advanced MM. Clinical evaluation of this agent continues, with enrolment at 250 mg b.i.d. ongoing, to further define the safety and tolerability at this dose level and provide insight into the future uses of SAHA, either alone or in combination with other agents, to treat pts with advanced MM.

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Interaction between Grapefruit Juice and Praziquantel in Humans

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.46.5.1614-1616.2002 ◽

2002 ◽

Vol 46 (5) ◽

pp. 1614-1616 ◽

Cited By ~ 40

Author(s):

Nelly Castro ◽

Helgi Jung ◽

Roberto Medina ◽

Dinora González-Esquivel ◽

Mario Lopez ◽

...

Keyword(s):

Water Treatment ◽

Oral Dose ◽

Single Oral Dose ◽

Half Life ◽

Maximum Concentration ◽

Grapefruit Juice ◽

Time Curve ◽

Elimination Half Life ◽

Concentration Time ◽

Elimination Half

ABSTRACT After a single oral dose of praziquantel with 250 ml of grapefruit juice, the area under the concentration-time curve and the maximum concentration in plasma of praziquantel (C max) were significantly increased (C max for water treatment, 637.71 ± 128.5 ng/ml; and C max for grapefruit juice treatment, 1,037.65 ± 305.7 ng/ml, P < 0.05). No statistically significant differences were found in the time to maximum concentration of drug in plasma or elimination half-life.

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Hierarchical models for sharing information across populations in phase I dose-escalation studies

Statistical Methods in Medical Research ◽

10.1177/0962280217703812 ◽

2017 ◽

Vol 27 (11) ◽

pp. 3447-3459 ◽

Cited By ~ 3

Author(s):

Kristen M Cunanan ◽

Joseph S Koopmeiners

Keyword(s):

Clinical Trial ◽

Phase I ◽

Dose Escalation ◽

Hierarchical Models ◽

Hierarchical Modeling ◽

Maximum Tolerated Dose ◽

Phase I Clinical Trial ◽

Dose Finding ◽

Novel Treatment ◽

Number Of Patients

The primary goal of a phase I clinical trial in oncology is to evaluate the safety of a novel treatment and identify the maximum tolerated dose, defined as the maximum dose with a toxicity rate below some pre-specified threshold. Researchers are often interested in evaluating the performance of a novel treatment in multiple patient populations, which may require multiple phase I trials if the treatment is to be used with background standard-of-care that varies by population. An alternate approach is to run parallel trials but combine the data through a hierarchical model that allows for a different maximum tolerated dose in each population but shares information across populations to achieve a more accurate estimate of the maximum tolerated dose. In this manuscript, we discuss hierarchical extensions of three commonly used models for the dose–toxicity relationship in phase I oncology trials. We then propose three dose-finding guidelines for phase I oncology trials using hierarchical modeling. The proposed guidelines allow us to fully realize the benefits of hierarchical modeling while achieving a similar toxicity profile to standard phase I designs. Finally, we evaluate the operating characteristics of a phase I clinical trial using the proposed hierarchical models and dose-finding guidelines by simulation. Our simulation results suggest that incorporating hierarchical modeling in phase I dose-escalation studies will increase the probability of correctly identifying the maximum tolerated dose and the number of patients treated at the maximum tolerated dose, while decreasing the rate of dose-limiting toxicities and number of patients treated above the maximum tolerated dose, in most cases.

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