A phase 1 study of eribulin mesylate (E7389), a novel microtubule-targeting chemotherapeutic agent, in children with refractory or recurrent solid tumors: A Children's Oncology Group Phase 1 Consortium study (ADVL1314).

BACKGROUND: Eribulin mesylate is a novel anticancer agent that inhibits microtubule growth, without effects on shortening, and promotes nonproductive tubulin aggregate formation. We performed a phase 1 trial to determine the dose-limiting toxicities (DLTs), maximum tolerated or recommended phase 2 dose (MTD/RP2D), and pharmacokinetics (PK) of eribulin in children with refractory or recurrent solid (excluding central nervous system) tumors. METHODS: Eribulin was administered intravenously on days 1 and 8 in 21-day cycles. Three dose levels (1.1, 1.4, and 1.8 mg/m2 /dose) were evaluated using the rolling six design with additional patients enrolled into a PK expansion cohort at the MTD. PK samples were obtained following the day 1, cycle 1 dose. RESULTS: Twenty-three patients, ages 3-17 (median 14) years were enrolled; 20 were evaluable for toxicity. DLTs occurred in 0/6 and 1/6 subjects at the 1.1 and 1.4 mg/m2 /dose, respectively. One subject at the 1.4 mg/m2 /dose had grade 4 neutropenia and grade 3 fatigue. At the 1.8 mg/m2 /dose, 2/5 subjects experienced dose-limiting (grade 4) neutropenia. Grade 3/4 non-DLTs included lymphopenia and hypokalemia, while low-grade toxicities included anorexia and nausea. No episodes of grade > 2 corrected QT interval prolongation or peripheral neuropathy were reported. Eribulin pharmacokinetic parameters were highly variable; the median elimination half-life was 39.6 (range 24.2-96.4) hr. A partial response was observed in one patient (Ewing sarcoma). CONCLUSIONS: Eribulin was well tolerated in children with refractory or recurrent solid tumors with neutropenia identified as the primary DLT. The RP2D of eribulin is 1.4 mg/m2 /dose on days 1 and 8 of a 21-day cycle.

Effects of Ketoconazole on the Pharmacokinetics of Lenvatinib (E7080) in Healthy Participants.

BACKGROUND: Lenvatinib is an oral, multitargeted, tyrosine kinase inhibitor under clinical investigation in solid tumors. In vitro evidence indicates that lenvatinib metabolism may be modulated by ketoconazole, an inhibitor of CYP3A4 and p-glycoprotein. METHODS: In this Phase I, single-center, randomized, open-label, two-period, crossover study, healthy adults (18-55 years; N = 18) were randomized to one of two sequences (ketoconazole → placebo or vice versa). Ketoconazole (400 mg) or placebo was administered orally once daily for 18 days; a 5 mg dose of lenvatinib was orally administered on Day 5 of each treatment period. Blood samples were collected over 14 days and lenvatinib plasma concentrations measured by high-performance liquid chromatography/tandem mass spectrometry. RESULTS: Systemic exposure to lenvatinib increased slightly (15-19%) with coadministration of ketoconazole. Although the 90% confidence interval (CI) for area under the plasma concentration-time curve (AUC) was within the prespecified bioequivalence interval of 80-125%, Cmax slightly exceeded the 125% CI bound (134%). No changes in tmax, tlag, or t½ were observed. Thirteen subjects (72%) experienced treatment-emergent adverse events (11 mild, 2 moderate), most commonly headache (22%) and diarrhea (17%). CONCLUSIONS: Lenvatinib exposure was slightly increased by ketoconazole; however, the magnitude of the change was relatively small, and likely not clinically meaningful.

A randomized, three-treatment, three-period, six-sequence-crossover, single-center, bioequivalence study to evaluate the impact of different 10-mg crystalline forms on the pharmacokinetics of lenvatinib in healthy volunteers.

OBJECTIVE: This study assessed the impact of varying lenvatinib crystalline forms in 10-mg lenvatinib capsules on drug bioavailability in healthy volunteers. MATERIALS: Lenvatinib 10-mg capsules (low C and high C forms). METHODS: This randomized, three-period- crossover study compared the pharmacokinetics and safety of two crystalline forms of capsules (low C-form, <4% crystalline; high C-form, 38% crystalline) to a standard (ref Cform, 15% crystalline). RESULTS: 59 subjects were evaluable for pharmacokinetics. Test/reference ratios of the geometric least squares means (LSM) and 90% confidence intervals (CI) for AUC0-t (t up to 120 hours), AUC0-∞, and Cmax for low C-form vs. ref C-form were 101 (94.8, 107), 101 (95.3, 107), and 98.7 (88.6, 110), respectively; and for high C-form vs. ref C-form were 96.0 (92.1, 100), 96.5 (92.5, 101), and 90.6 (83.5, 98.4), respectively. The incidence of treatment-emergent adverse events (TEAE) and treatment-related adverse events (TRAE) were comparable between all formulations (TEAE range 20-24%; TRAE range 15-19%). One serious TRAE (spontaneous abortion) occurred in the low C-form group. CONCLUSIONS: For both comparisons, the 90% CIs of the test/reference ratios were within the regulatory acceptance range (80-125%), suggesting that both test formulations (low Cform and high C-form) were bioequivalent to the reference formulation for Cmax, AUC0-t, and AUC0-∞.

Influence of hepatic impairment on lenvatinib pharmacokinetics following single-dose oral administration.

This open-label, single-dose study assessed lenvatinib pharmacokinetics (PK) in subjects with normal hepatic function (n = 8) and mild, moderate, or severe hepatic impairment (n = 6 each). Subjects received 10 mg oral lenvatinib, except those with severe hepatic impairment (5 mg). Plasma and urine samples were collected over 14 days; free and total lenvatinib and its metabolites were analyzed using validated chromatography/spectrometry. PK parameters were estimated using noncompartmental analysis. There were no clinically meaningful effects of mild or moderate hepatic impairment on lenvatinib PK. Dose-normalized Cmax for free lenvatinib was 7.0, 3.7, 5.7, and 5.6 ng/mL in subjects with normal hepatic function, mild, moderate, and severe hepatic impairment, respectively. There was no consistent trend, although dose-normalized Cmax was lower for all subjects with hepatic impairment. AUCs increased 170% and t1/2 increased (37 versus 23 hours) in subjects with severe hepatic impairment. Changes in exposure based on total plasma concentrations were generally less than those based on free concentrations, suggesting changes in plasma protein binding in subjects with severe hepatic impairment. Lenvatinib was generally well tolerated. Subjects with severe hepatic impairment should begin lenvatinib treatment at a reduced dose of 14 mg versus 24 mg for subjects with normal liver function and subjects with mild or moderate hepatic impairment.

Effect of rifampicin on the pharmacokinetics of lenvatinib in healthy adults.

BACKGROUND AND OBJECTIVES: Lenvatinib is an oral, multitargeted tyrosine kinase inhibitor under clinical investigation in solid tumours. This study evaluated the influence of P-glycoprotein (P-gp) inhibition (single-dose rifampicin) and simultaneous cytochrome P450 3A4 (CYP3A4)/P-gp induction (multiple-dose rifampicin) on lenvatinib pharmacokinetics. METHODS: This Phase I, single-centre, single-dose (lenvatinib mesylate 24 mg), open-label, sequential study enrolled 15 healthy volunteers. Three regimens were administered over three periods: Period (P) 1 (Days 1-8), P2 (Days 15-22) and P3 (Days 29-50), with a 14-day (first dose) and 28-day (second dose) washout period after lenvatinib mesylate administration (Day 1, Day 15 and Day 43). In P2, a single oral dose of rifampicin (600 mg) was coadministered with lenvatinib. In P3, rifampicin was administered daily (600 mg) for 21 days (Days 29-49). Serial blood samples were collected, and plasma concentrations of total (protein bound + unbound) and free (unbound) lenvatinib and total metabolites (M1, M2, M3 and M5) were measured by validated high-performance liquid chromatography/tandem mass spectrometry. RESULTS: Single-dose rifampicin (P-gp inhibition) increased area under the plasma concentration-time curve from time zero to infinity (AUC0-∞) of free and total lenvatinib by 32 and 31 %, respectively. Multiple-dose rifampicin (simultaneous P-gp and CYP3A4 induction) decreased lenvatinib AUC0-∞ (total: 18 %; free: 9 %). Treatment-emergent adverse events were mild or moderate and occurred in 7 subjects (47 %). CONCLUSION: Lenvatinib exposure was increased by P-gp inhibition; however, based on free concentrations, simultaneous P-gp and CYP3A4 induction results met the prespecified bioequivalence 90 % confidence interval. Overall, the magnitude of these changes was relatively small, and likely not clinically meaningful.

Effect of lenvatinib (E7080) on the QTc interval: results from a thorough QT study in healthy volunteers.

PURPOSE: QT assessment of oncology drugs is generally challenging because they are genotoxic and, of necessity,they require multisite evaluation in cancer patients. Lenvatinib is not genotoxic, therefore, this thorough QT (TQT)study with lenvatinib, a multityrosine kinase inhibitor, was undertaken utilizing healthy volunteers and concentration effect modeling to project the TQT effect at high plasma levels. METHODS: Fifty-two healthy subjects randomly received single doses of lenvatinib 32 mg, placebo, or moxifloxacin 400 mg in a three-way crossover study. Serial electrocardiograms were recorded, and the effect on placebo corrected change-from-baseline QTcF (ΔΔQTcF) was evaluated. The relationship between lenvatinib plasma concentrations and QTcF was analyzed with linear mixed effects modeling. RESULTS: L envatinib mildly lowered the heart rate by 5­8 bpm during the first 12 h after dosing. ΔΔQTcF was shortened with a peak effect of −5.72 ms (90 % confidence interval (90 % CI) −7.76 to −3.69 ms) at 6 h postdosing.The upper bound of mean ΔΔQTcF did not exceed 2 ms at any time point postdosing. A concentration-dependent effect of lenvatinib on ΔΔQTcF was identified with an estimated population intercept of −2.96 ms (90 % CI −4.49 to−1.43 ms; P = 0.0016) and a negative slope of −0.0045(90 % CI −4.49 to −1.43) ms per ng/mL, respectively. The safety profile after a single dose of lenvatinib was acceptable,with adverse events (AEs) of mild-to-moderate severity and no serious AEs. CONCLUSIONS: L envatinib had no clinically relevant effect on the QTc interval. Concentration-effect modeling supports the lack of QTc prolongation at high plasma concentrations.

Evaluation of the effects of formulation and food on the pharmacokinetics of lenvatinib (E7080) in healthy volunteers.

OBJECTIVE: To evaluate the effect of formulation and a high-fat meal on the pharmacokinetics of orally administered lenvatinib (E7080). MATERIALS: Lenvatinib 10-mg capsule and tablet. METHODS: Pharmacokinetics and safety of a single 10-mg lenvatinib dose were evaluated in healthy subjects in two randomized, two-period, crossover, phase 1, bioavailability trials. The first compared a new capsule formulation with an older tablet formulation (n = 20 subjects); the second evaluated the influence of a standard high-fat meal on the relative bioavailability of the capsule formulation (n = 16 subjects). Geometric least squares mean ratios of AUC0-∞, maximum observed concentration (Cmax), and AUC0-t were determined. tmax, tlag (food effect only), and t1/2,z were also calculated, and descriptive statistics were provided. RESULTS: A total of 36 healthy volunteers were enrolled in the two studies (mean ages 29 and 33 years). In the formulation study, AUC0-∞ and AUC0-t of the capsule formulation were ~ 10% less than the tablet formulation, and Cmax for the capsule formulation was ~ 14% lower. 90% Confidence intervals (CIs) for both AUCs were within the 80 - 125% CI, which is generally considered to denote bioequivalence, while the lower bound of the interval for Cmax was 79.8%. tmax and t1/2,z were comparable. For the capsule formulation, the mean (%CV) t1/2,z was 27.6 hours (27.3) and the median (range) tmax was 2.0 hours (2 - 4). In the food effect study, lenvatinib's AUC0-∞ and AUC0-t increased ~ 6% and 4% with the high-fat meal. Cmax following a high-fat meal was 5% lower than following administration in the fasted state. Administration with food delayed lenvatinib's tmax (2 vs. 4 hours). 90% CIs for AUCs were within the 80 - 125% CI, while the CI for Cmax was 72.1 - 126.4%. The single 10-mg dose demonstrated an acceptable tolerability profile; treatment-emergent adverse events occurred in 9 subjects (25%) overall and were typically mild in severity. CONCLUSIONS: These studies show that a new capsule formulation produces slightly lower exposure (~10 - 14%) to lenvatinib compared with the original tablet formulation, and that oral administration with a high-fat meal does not significantly affect exposure, although absorption is delayed. Thus, lenvatinib can be administered without regard to the timing of meals.