Peter Hellemans

Combination of ibrutinib with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for treatment-naive patients with CD20-positive B-cell non-Hodgkin lymphoma: a non-randomised, phase 1b study

BACKGROUND Present first-line therapy for diffuse large B-cell lymphoma, a subtype of non-Hodgkin lymphoma, is rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). Ibrutinib, a novel oral Brutons tyrosine kinase inhibitor, has shown single-drug activity in relapsed or refractory B-cell malignancies. We investigated the safety and efficacy of ibrutinib in combination with R-CHOP for patients with previously untreated CD20-positive B-cell non-Hodgkin lymphoma. METHODS In this phase 1b, open-label, non-randomised study, patients were recruited across six centres in the USA and France. Eligibility was age 18 years or older and treatment-naive histopathologically confirmed CD20-positive B-cell non-Hodgkin lymphoma. In the dose-escalation phase (part 1), patients with diffuse large B-cell lymphoma, mantle-cell lymphoma, or follicular lymphoma were enrolled. The primary objective was to determine a recommended phase 2 dose of ibrutinib with a standard R-CHOP regimen, by assessing safety in all patients who received treatment. Patients received ibrutinib 280 mg, 420 mg, or 560 mg per day in combination with a standard R-CHOP regimen every 21 days. Safety of the recommended phase 2 dose was then assessed in a dose-expansion population, which consisted of patients with newly diagnosed diffuse large B-cell lymphoma (part 2). Secondary objectives included assessments of the proportion of patients who had an overall response, pharmacokinetics, and pharmacodynamics. This trial is registered with ClinicalTrials.gov, number NCT01569750. FINDINGS From June 22, 2012, to March 25, 2013, 33 patients were enrolled (part 1: 17; part 2: 16) and 32 received ibrutinib plus R-CHOP treatment (one patient in the part 2 cohort withdrew). The maximum tolerated dose was not reached and the recommended phase 2 dose for ibrutinib was 560 mg per day. The most common grade 3 or greater adverse events included neutropenia (73% [24 of 33 patients]), thrombocytopenia (21% [seven patients]), and febrile neutropenia and anaemia (18% each [six patients]). The most frequently reported serious adverse events were febrile neutropenia (18% [six patients]) and hypotension (6% [two patients]). 30 (94%) of 32 patients who received one or more doses of combination treatment achieved an overall response. All 18 patients with diffuse large B-cell lymphoma who received the recommended phase 2 dose had an overall response. For those subtyped and treated at the recommended phase 2 dose, five (71%) of seven patients with the germinal centre B-cell-like subtype and two (100%) patients with the non-germinal centre B-cell-like subtype had a complete response. R-CHOP did not affect pharmacokinetics of ibrutinib, and ibrutinib did not alter the pharmacokinetics of vincristine. Pharmacodynamic data showed Brutons tyrosine kinase was fully occupied (>90% occupancy) at the recommended phase 2 dose. INTERPRETATION Ibrutinib is well tolerated when added to R-CHOP, and could improve responses in patients with B-cell non-Hodgkin lymphoma, but our findings need confirmation in a phase 3 trial. FUNDING Janssen.

A Phase I Study of Quisinostat (JNJ-26481585), an Oral Hydroxamate Histone Deacetylase Inhibitor with Evidence of Target Modulation and Antitumor Activity, in Patients with Advanced Solid Tumors

Purpose: To determine the maximum-tolerated dose (MTD), dose-limiting toxicities (DLT), and pharmacokinetic and pharmacodynamic profile of quisinostat, a novel hydroxamate, pan-histone deacetylase inhibitor (HDACi). Experimental Design: In this first-in-human phase I study, quisinostat was administered orally, once daily in three weekly cycles to patients with advanced malignancies, using a two-stage accelerated titration design. Three intermittent schedules were subsequently explored: four days on/three days off; every Monday, Wednesday, Friday (MWF); and every Monday and Thursday (M-Th). Toxicity, pharmacokinetics, pharmacodynamics, and clinical efficacy were evaluated at each schedule. Results: Ninety-two patients were treated in continuous daily (2–12 mg) and three intermittent dosing schedules (6–19 mg). Treatment-emergent adverse events included: fatigue, nausea, decreased appetite, lethargy, and vomiting. DLTs observed were predominantly cardiovascular, including nonsustained ventricular tachycardia, ST/T-wave abnormalities, and other tachyarhythmias. Noncardiac DLTs were fatigue and abnormal liver function tests. The maximum plasma concentration (Cmax) and area under the plasma concentration–time curve (AUC) of quisinostat increased proportionally with dose. Pharmacodynamic evaluation showed increased acetylated histone 3 in hair follicles, skin and tumor biopsies, and in peripheral blood mononuclear cells as well as decreased Ki67 in skin and tumor biopsies. A partial response lasting five months was seen in one patient with melanoma. Stable disease was seen in eight patients (duration 4–10.5 months). Conclusions: The adverse event profile of quisinostat was comparable with that of other HDACi. Intermittent schedules were better tolerated than continuous schedules. On the basis of tolerability, pharmacokinetic predictions, and pharmacodynamic effects, the recommended dose for phase II studies is 12 mg on the MWF schedule. Clin Cancer Res; 19(15); 4262–72. ©2013 AACR.

Effect of CYP3A perpetrators on ibrutinib exposure in healthy participants

Ibrutinib (PCI‐32765), a potent covalent inhibitor of Brutons tyrosine kinase, has shown efficacy against a variety of B‐cell malignancies. Given the prominent role of CYP3A in ibrutinib metabolism, effect of coadministration of CYP3A perpetrators with ibrutinib was evaluated in healthy adults. Ibrutinib (120 mg [Study 1, fasted], 560 mg [studies 2 (fasted), and 3 (nonfasted)]) was given alone and with ketoconazole [Study 1; 400 mg q.d.], rifampin [Study 2; 600 mg q.d.], and grapefruit juice [GFJ, Study 3]. Lower doses of ibrutinib were used together with CYP3A inhibitors [Study 1: 40 mg; Study 3: 140 mg], as safety precaution. Under fasted condition, ketoconazole increased ibrutinib dose‐normalized (DN) exposure [DN‐AUClast: 24‐fold; DN‐Cmax: 29‐fold], rifampin decreased ibrutinib exposure [Cmax: 13‐fold; AUClast: 10‐fold]. Under nonfasted condition, GFJ caused a moderate increase [DN‐Cmax: 3.5‐fold; DN‐AUC: 2.2‐fold], most likely through inhibition of intestinal CYP3A. Half‐life was not affected by CYP perpetrators indicating the interaction was mainly on first‐pass extraction. All treatments were well‐tolerated.

The c-Met Tyrosine Kinase Inhibitor JNJ-38877605 Causes Renal Toxicity through Species-Specific Insoluble Metabolite Formation

Purpose: The receptor tyrosine kinase c-Met plays an important role in tumorigenesis and is a novel target for anticancer treatment. This phase I, first-in-human trial, explored safety, pharmacokinetics, pharmacodynamics, and initial antitumor activity of JNJ-38877605, a potent and selective c-Met inhibitor. Experimental Design: We performed a phase I dose-escalation study according to the standard 3+3 design. Results: Even at subtherapeutic doses, mild though recurrent renal toxicity was observed in virtually all patients. Renal toxicity had not been observed in preclinical studies in rats and dogs. Additional preclinical studies pointed toward the rabbit as a suitable toxicology model, as the formation of the M10 metabolite of JNJ-38877605 specifically occurred in rabbits and humans. Additional toxicology studies in rabbits clearly demonstrated that JNJ-38877605 induced species-specific renal toxicity. Histopathological evaluation in rabbits revealed renal crystal formation with degenerative and inflammatory changes. Identification of the components of these renal crystals revealed M1/3 and M5/6 metabolites. Accordingly, it was found that humans and rabbits showed significantly increased systemic exposure to these metabolites relative to other species. These main culprit insoluble metabolites were generated by aldehyde oxidase activity. Alternative dosing schedules of JNJ-3877605 and concomitant probenecid administration in rabbits failed to prevent renal toxicity at dose levels that could be pharmacologically active. Conclusions: Combined clinical and correlative preclinical studies suggest that renal toxicity of JNJ-38877605 is caused by the formation of species-specific insoluble metabolites. These observations preclude further clinical development of JNJ-38877605. Clin Cancer Res; 21(10); 2297–304. ©2015 AACR.

Phase II multicentre trial of oral quisinostat, a histone deacetylase inhibitor, in patients with previously treated stage IB-IVA mycosis fungoides/Sézary syndrome.

Quisinostat is a hydroxamate, second‐generation, orally available pan‐histone deacetylase inhibitor.

Phase i and pharmacological study of the broad-spectrum tyrosine kinase inhibitor JNJ-26483327 in patients with advanced solid tumours

Background:JNJ-26483327 is an oral, potent, multi-targeted tyrosine kinase inhibitor, inhibiting kinases of epidermal growth factor receptor (EGFR)-1, -2 and -4, rearranged during transfection (RET) receptor, vascular endothelial growth factor receptor (VEGFR)-3 and Src family (Lyn, Fyn, Yes) at low nanomolar concentrations. This phase I, accelerated titration study assessed maximum tolerated dose, safety, pharmacokinetics and pharmacodynamic effects of JNJ-26483327.Methods:Nineteen patients with advanced cancers received JNJ-26483327 continuous twice daily (BID) in escalating dose cohorts ranging from 100 to 2100 mg. Pharmacodynamic effects were assessed in paired skin biopsies and blood.Results:JNJ-26483327 was well tolerated in doses up to 1500 mg BID, with target-inhibition-related toxicity such as diarrhoea and skin rash, and other common reported toxicities being nausea, vomiting, anorexia and fatigue. At 2100 mg, two episodes of dose-limiting toxicity were observed, consisting of grade 3 anorexia and a combination of grade 3 anorexia and fatigue, respectively. Pharmacokinetics were dose proportional up to 1500 mg in which plasma levels were obtained showing anti-tumour activity in xenograft mouse models. Pharmacodynamic analysis did not show a substantial effect on expression of Ki-67, p27kip1, phosphorylated mitogen-activated protein kinase, phosphorylated Akt and EGFR, and serum levels of sVEGFR-2, VEGF-C and VEGF-D remained unchanged. Stable disease was noted in six patients (32%).Conclusion:JNJ-26483327 is well tolerated and shows a predictable pharmacokinetic profile; the recommended dose for further studies is 1500 mg BID.

Quisinostat, bortezomib, and dexamethasone combination therapy for relapsed multiple myeloma

Abstract The maximum tolerated dose (MTD) of quisinostat + bortezomib + dexamethasone in patients with relapsed multiple myeloma was evaluated in a phase-1b, open-label, multicenter, ‘3 + 3’ dose-escalation study. Patients received escalating doses of oral quisinostat (6 mg [n = 3], 8 mg [n = 3], 10 mg [n = 6], and 12 mg [n = 6] on days 1, 3, and 5/week) plus subcutaneous bortezomib (1.3 mg/m2) and oral dexamethasone (20 mg) in cycles of 21 (cycles 1–8) or 35 d (cycles 9–11) until MTD was determined. No dose-limiting toxicities were reported in 6/8 mg groups except ventricular fibrillation (Grade 4 cardiac arrest, n = 1 [10 mg] cycle 6) and clinically significant cardiac toxicities (Grade 3 QTc prolongation, Grade 3 atrial fibrillation, n = 2 [12 mg]). Thrombocytopenia (n = 11), asthenia (n = 10), and diarrhea (n = 12) were most common adverse events. Overall, 88.2% patients achieved treatment response, median duration of response, and median progression-free survival were 9.4 and 8.2 months, respectively. The MTD of quisinostat was established as 10 mg thrice weekly oral dose with bortezomib + dexamethasone.

Single-dose pharmacokinetics of ibrutinib in subjects with varying degrees of hepatic impairment*

Abstract This open-label, single-dose study was designed to characterize pharmacokinetics and safety profile of ibrutinib in hepatically impaired subjects. Each subject received single oral dose of ibrutinib (140 mg) following an overnight fast (hepatic impairment-mild [n = 6], moderate [n = 10], and severe [n = 8]; healthy control [n = 6]). Subjects with hepatic impairment showed significant increase in ibrutinib plasma exposures and fraction unbound ibrutinib. Compared to control group, mean exposure (AUClast; unbound) in mild, moderate, and severe cohorts was 4.1-, 9.8-, 13.4-fold higher, respectively. Terminal half-life trended slightly longer in moderately and severely impaired subjects, but risk of accumulation on repeated dosing appears negligible as half-life did not exceed 10 h. Based on observed effects on exposure, reduced doses are recommended for patients with mild and moderate liver impairment (Child–Pugh Class A and B), whereas 140 mg is considered too high for severely impaired patients (Class-C). A single dose of 140 mg was well tolerated in this study (NCT01767948).

Abstract 4637: Evaluation of the pharmacokinetics and food effect of oral ibrutinib in healthy subjects and chronic lymphocytic leukemia patients

Chronic lymphocytic leukemia (CLL) is a B-cell malignancy treated with chemoimmunotherapy. Such treatment results in high response rates but patients may eventually relapse and require alternate therapies. Ibrutinib (PCI-32765), a recently developed novel treatment, is unique in its mechanism as it inhibits Bruton9s tyrosine kinase, a key kinase in the B-cell receptor signaling pathway. It9s a Biopharmaceutics Classification Systems (BCS) class 2 compound and is metabolized rapidly by CYP3A. Three studies were conducted. The primary objectives were to assess the pharmacokinetics (PK) of ibrutinib under fed and fasted conditions and to assess the impact of food intake timing. Additionally, the safety and tolerability of ibrutinib were assessed. Study 1 was a randomized, open-label, single-center, single-dose, 4-way crossover study in 44 healthy subjects. Study 2 was a multicenter, randomized, repeated-dose crossover study in 16 patients with relapsed or refractory CLL. The ibrutinib dose was 420 mg in both. Study 3 was an open-label, single-center, sequential study to assess absolute bioavailability of ibrutinib 560 mg in 8 healthy subjects. Ibrutinib was well tolerated in these studies. There were no serious adverse events (AEs) or discontinuations due to an AE. There were no clinically significant changes in laboratory safety parameters, electrocardiograms, or vital signs. Administration of ibrutinib to healthy subjects under fasting conditions resulted in approximately 60% of exposure compared to drug intake either 30 min before or 2 h after a high-fat meal. When ibrutinib was taken 30 min after a meal, drug exposure was comparable to the dosing conditions of either 30 min before or 2 h after the meal. Study 2 revealed that under fed conditions, the maximum concentration was 2.24 times greater and the area under the curve was 1.65 times greater compared to the fasted conditions, but similar to uncontrolled food intake conditions. A similar food effect was observed in study 3, in which a standard meal was consumed starting 30 min after dosing. When corrected for repeated dosing in patients, the PK parameters in healthy subjects and patients were comparable. The observed food effect is most likely the result of a decreased (intestinal and hepatic) first-pass effect, rather than an effect on solubilization. Since ibrutinib is a highly permeable compound, residence time in the gut and liver cells could be reduced when mesenteric and portal vein blood flow is increased under fed conditions, making ibrutinib less available to CYP3A clearance. The effect on bioavailability may outweigh the higher clearance due to liver blood flow. In conclusion, food causes no more than a doubling in ibrutinib systemic exposure. Considering the favorable safety profile, ibrutinib can be administered with or without food. Citation Format: Jan de Jong, Juthamas Sukbuntherng, Donna Skee, Joe Murphy, Susan O9Brien, John C. Byrd, Danelle James, Peter Hellemans, Juhui James Jiao, Vijay Chauhan, Italo Poggesi, Erik Mannaert. Evaluation of the pharmacokinetics and food effect of oral ibrutinib in healthy subjects and chronic lymphocytic leukemia patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4637. doi:10.1158/1538-7445.AM2014-4637

A drug–drug interaction study of ibrutinib with moderate/strong CYP3A inhibitors in patients with B-cell malignancies

Abstract This was an open-label, multicenter, phase-1 study to evaluate the drug interaction between steady-state ibrutinib and moderate (erythromycin) and strong (voriconazole) CYP3A inhibitors in patients with B-cell malignancies and to confirm dosing recommendations. During cycle 1, patients received oral ibrutinib 560 mg qd alone (Days 1–4 and 14–18), and ibrutinib 140 mg (Days 5–13; 19–27) plus erythromycin 500 mg tid (Days 5–11) and voriconazole 200 mg bid (Days 19–25). Twenty-six patients (median [range] age: 64.5 [50–88] years) were enrolled. Geometric mean ratio (90% confidence intervals) after co-administration of ibrutinib 140 mg with erythromycin and voriconazole was 74.7 (53.97–103.51) and 143.3 (107.77–190.42), respectively, versus ibrutinib 560 mg alone. The most common (≥20%) adverse events were diarrhea (27%) and neutropenia (23%). The results demonstrate that ibrutinib 140 mg with voriconazole or erythromycin provides exposure within the clinical range for patients with B-cell malignancies.