Safety and efficacy of acalabrutinib and obinutuzumab in treatment-naive chronic lymphocytic leukemia: a Japanese phase 1 study.

This report focuses on part 3 of a multicenter, open-label, phase 1 study (NCT03198650) assessing the safety, pharmacokinetics (PK), pharmacodynamics (PD), and antitumor activity of acalabrutinib plus obinutuzumab in Japanese patients with treatment-naive (TN) chronic lymphocytic leukemia (CLL). Ten patients were included; median age was 68 years. With a median treatment duration of 27.2 months, treatment-emergent adverse events (AEs) occurred in all patients (grade ≥3, 70%), and the most common AEs were anemia and headache (40% each). One patient had a grade 4 AE of neutropenia (the only dose-limiting toxicity). PK results suggested no marked effects of concomitant obinutuzumab treatment on the exposure of acalabrutinib. PD assessment indicated that combination therapy provided >98% Bruton tyrosine kinase (BTK) occupancy. Overall response rate (ORR) was 100% with median duration of response (DoR) and median progression-free survival (PFS) not reached. Treatment with acalabrutinib plus obinutuzumab was generally safe and efficacious in adult Japanese patients with TN CLL.

Safety, tolerability, pharmacokinetics, and antitumor activity of adavosertib in Japanese patients with advanced solid tumors: A phase I, open-label study.

INTRODUCTION: We aimed to assess the safety, pharmacokinetic profile, and antitumor activity of adavosertib monotherapy in Japanese patients with advanced solid tumors. MATERIALS AND METHODS: This was a single-center, open-label, phase I study with two consecutive cohorts (250 mg and 200 mg cohorts). Patients received adavosertib at 250 mg or 200 mg, orally once daily for 5 days on and 2 days off for Weeks 1 and 2 of a 21-day cycle. RESULTS: Dose-limiting toxicities (Grade 3 febrile neutropenia) occurred in 2/6 patients in the 250 mg cohort. None of the three patients in the 200 mg cohort developed dose-limiting toxicities. The most frequent treatment-emergent adverse event was nausea (250 mg: 83.3 %; 200 mg: 100.0 %). Median time to peak drug concentration was 4.03 and 2.08 h after the first dose and 2.82 and 1.90 h after multiple dosing in the 250 and 200 mg cohorts, respectively; respective mean terminal elimination half-lives were 7.36 and 7.30 h (first dose) and 10.55 and 8.88 h (multiple dosing). Systemic exposure increased in a slightly more than dose-proportional manner. No RECIST v1.1 response was observed. Disease control rate was 0 % and 33.3 % in the 250 and 200 mg cohorts, respectively. One patient (33.3 %) in the 200 mg cohort showed a best overall response of stable disease at ≥ 8 weeks; the rest showed progressive disease. CONCLUSIONS: Adavosertib 200 mg once daily was well tolerated in this patient population and no safety concerns were raised. Exposure increased in a slightly more than dose-proportional manner and limited antitumor activity was shown. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04462952.

Prediction of the Contribution Ratio of a Target Metabolic Enzyme to Clearance from Chemical Structure Information.

The contribution ratio of metabolic enzymes such as cytochrome P450 to in vivo clearance (fraction metabolized: fm) is a pharmacokinetic index that is particularly important for the quantitative evaluation of drug-drug interactions. Since obtaining experimental in vivo fm values is challenging, those derived from in vitro experiments have often been used alternatively. This study aimed to explore the possibility of constructing machine learning models for predicting in vivo fm using chemical structure information alone. We collected in vivo fm values and chemical structures of 319 compounds from a public database with careful manual curation and constructed predictive models using several machine learning methods. The results showed that in vivo fm values can be obtained from structural information alone with a performance comparable to that based on in vitro experimental values and that the prediction accuracy for the compounds involved in CYP induction or inhibition is significantly higher than that by using in vitro values. Our new approach to predicting in vivo fm values in the early stages of drug discovery should help improve the efficiency of the drug optimization process.

Gefitinib exposure and occurrence of interstitial lung disease in Japanese patients with non-small-cell lung cancer.

PURPOSE: A prospective, multicenter, large-scale cohort with a nested case-control study (NCT00252759) was conducted to identify and quantify risk factors for interstitial lung disease (ILD) in Japanese patients with non-small-cell lung cancer who received gefitinib. This study reports the association between gefitinib exposure and the occurrence of ILD. METHODS: A total of 1891 gefitinib plasma concentrations from 336 patients were measured after first dose, at steady state, and at time of ILD occurrence. Influences of demographic and pathophysiological factors on pharmacokinetics were investigated by non-linear mixed-effect modeling. The exposure to gefitinib was compared between patients without and with ILD occurrence to explore risks associated with gefitinib-induced ILD. Intra-patient comparison of exposure was also conducted between times at ILD development and normal states. RESULTS: In the population pharmacokinetic analysis for gefitinib, α1-acid glycoprotein (AGP), age, body weight, and concomitant use of cytochrome P450 3A4 inducers were significant covariates on oral clearance (CL/F). AGP and body weight were also identified as factors affecting the volume of distribution. CL/F was significantly lower at the time of ILD occurrence than normal states. Patients who developed ILD tended to show higher exposure to gefitinib than those without ILD; however, these differences were not statistically significant. On the other hand, exposure at the time of ILD occurrence was significantly elevated compared to the time of normal state within the same patients. CONCLUSIONS: Significant elevation of exposure of gefitinib was observed at the time of ILD occurrence, suggesting reduction of CL/F could be associated with ILD-induced AGP elevation. Increase in exposure of gefitinib is unlikely to be a robust predictor of ILD and does not warrant any dose modifications.

Safety and tolerability of the olaparib tablet formulation in Japanese patients with advanced solid tumours.

PURPOSE: This was the first Phase I study to assess the safety and tolerability of the tablet formulation of olaparib (Lynparza™), an oral poly(ADP-ribose) polymerase inhibitor, in Japanese patients with advanced solid tumours. The pharmacokinetic profile and antitumour activity of olaparib tablets were also assessed. METHODS: In this open-label, multicentre study (D081BC00001; NCT01813474), a single dose of olaparib (200 or 300 mg, tablets) was administered on day 1, followed 48 h afterwards by multiple dosing (200 or 300 mg twice daily [bid]) for 28-day cycles. Doses were escalated in successive cohorts, with an expansion cohort enrolled at the highest dose that was confirmed to be tolerable during dose escalation. RESULTS: Twenty-eight patients were enrolled and 23 were treated (n = 4, 7 and 12 at 200, 300 and 300 [expansion] mg bid, respectively). No patients experienced a dose-limiting toxicity, so the maximum tolerated dose was not defined. The most frequent adverse events were nausea (43.5 %), decreased appetite (30.4 %), anaemia (26.1 %) and constipation (26.1 %). No patient had dose reductions, two had dose interruptions, and two discontinued treatment because of adverse events. Absorption of olaparib was rapid following single and multiple dosing, and plasma concentrations declined biphasically after single dosing. No patients had a confirmed antitumour response. CONCLUSIONS: Olaparib tablet doses of 200 and 300 mg bid were considered tolerable in Japanese patients with advanced solid tumours. Consistent with the global olaparib programme, 300 mg bid was selected as the recommended tablet dose for future studies. CLINICAL TRIAL REGISTRATION NUMBER: NCT01813474.

Safety and tolerability of AZD5363 in Japanese patients with advanced solid tumors.

PURPOSE: Investigate the safety and tolerability of AZD5363 and define a recommended dose for evaluation in Japanese patients with advanced solid malignancies. METHODS: AZD5363 was administered orally as a single dose, and then the dose was escalated to twice daily (bid) in separate continuous (every day) and intermittent (4 days on, 3 days off [4/3] or 2 days on, 5 days off [2/5]) dosing schedules to reach recommended doses defined by dose-limiting toxicity (DLT). Doses for continuous, 4/3, and 2/5 intermittent dosing schedules were 80-400, 360-480, and 640 mg, respectively, and were informed by results from an equivalent study in Caucasian patients. RESULTS: Forty-one patients received AZD5363. DLTs were only experienced with continuous dosing. 97.6 % of patients reported at least one adverse event (AE); most common were diarrhea (78.0 %), hyperglycemia (68.3 %), nausea (56.1 %), and maculopapular rash (56.1 %). Grade ≥3 AEs were reported by 63.4 % of patients. Exposure of AZD5363 was generally dose proportional for both single and multiple doses. Single-dose pharmacokinetics of AZD5363 was generally predictive of multiple-dose pharmacokinetics. Confirmed partial responses were reported by two patients, both of whom were Akt1 (E17K) mutation positive. One patient in the 480 mg bid 4/3 dosing cohort maintained partial response for >2 years. CONCLUSIONS: Intermittent dosing of AZD5363 was more tolerable than continuous dosing. 480 mg bid intermittent 4/3 dosing for AZD5363 monotherapy was selected for further investigation. Preliminary evidence of antitumor activity was observed. Akt1 (E17K) is a potent driver mutation that may predict clinical response to AZD5363.

Anti-inflammatory effects of adenosine N1-oxide.

BACKGROUND: Adenosine is a potent endogenous anti-inflammatory and immunoregulatory molecule. Despite its promise, adenosine's extremely short half-life in blood limits its clinical application. Here, we examined adenosine N1-oxide (ANO), which is found in royal jelly. ANO is an oxidized product of adenosine at the N1 position of the adenine base moiety. We found that it is refractory to adenosine deaminase-mediated conversion to inosine. We further examined the anti-inflammatory activities of ANO in vitro and in vivo. METHODS: The effect of ANO on pro-inflammatory cytokine secretion was examined in mouse peritoneal macrophages and the human monocytic cell line THP-1, and compared with that of adenosine, synthetic adenosine receptor (AR)-selective agonists and dipotassium glycyrrhizate (GK2). The anti-inflammatory activity of ANO in vivo was examined in an LPS-induced endotoxin shock model in mice. RESULTS: ANO inhibited secretion of inflammatory mediators at much lower concentrations than adenosine and GK2 when used with peritoneal macrophages and THP-1 cells that were stimulated by LPS plus IFN-γ. The potent anti-inflammatory activity of ANO could not be solely accounted for by its refractoriness to adenosine deaminase. ANO was superior to the synthetic A1 AR-selective agonist, 2-chloro-N(6)-cyclopentyladenosine (CCPA), A2A AR-selective agonist, 2-[p-(2-carboxyethyl)phenethylamino]-5'-N-ethylcarboxamideadenosine hydrochloride (CGS21680), and A3 AR-selective agonist, N(6)-(3-iodobenzyl)adenosine-5'-N-methyluronamide (IB-MECA), in suppressing the secretion of a broad spectrum of pro-inflammatory cytokines by peritoneal macrophages. The capacities of ANO to inhibit pro-inflammatory cytokine production by THP-1 cells were comparable with those of CCPA and IB-MECA. Reflecting its potent anti-inflammatory effects in vitro, intravenous administration of ANO significantly reduced lethality of LPS-induced endotoxin shock. A significant increase in survival rate was also observed by oral administration of ANO. Mechanistic analysis suggested that the up-regulation of the anti-inflammatory transcription factor c-Fos was, at least in part, involved in the ANO-induced suppression of pro-inflammatory cytokine secretion. CONCLUSIONS: Our data suggest that ANO, a naturally occurring molecule that is structurally close to adenosine but is functionally more potent, presents potential strategies for the treatment of inflammatory disorders.

A Phase I, dose-finding and pharmacokinetic study of olaparib (AZD2281) in Japanese patients with advanced solid tumors.

Olaparib (AZD2281) is an orally active Poly(ADP-ribose) polymerase (PARP) inhibitor with favorable antitumor activity in advanced ovarian and breast cancers with BRCA1/2 mutations in Western (USA and European) studies. This Phase I dose-finding study evaluated the tolerability, pharmacokinetics, PARP inhibitory activity, and antitumor activity of olaparib in Japanese patients with solid tumors. Olaparib was administered as a single-dose on day 1, followed by twice-daily dosing for 28 days from 48 h after a single dose. Doses were escalated from 100 mg b.i.d. in successive cohorts, up to a maximum of 400 mg b.i.d. The present study enrolled 12 patients (n = 3, 3, and 6 in 100, 200 and 400-mg b.i.d. levels, respectively). The most common adverse events were nausea, increased blood creatinine, decreased hematocrit, leukopenia and lymphopenia; dose-limiting toxicities were not observed up to and including the 400-mg b.i.d. dose level. Following twice-daily dosing, olaparib showed no marked increase in exposure at steady state over that expected from the single-dose pharmacokinetics. PARP-1 inhibition was observed from the 100-mg b.i.d. dose level in peripheral blood mononuclear cells from 6 h post-dose on day 1 during the multiple-dosing period. A patient with metastatic breast cancer (100 mg b.i.d.) had a partial response for 13 months and four patients (two each in the 200 and 400-mg b.i.d. levels) had stable disease >8 weeks. Olaparib was well tolerated up to the 400-mg b.i.d. dose in Japanese patients with solid tumors. Preliminary evidence of antitumor activity was observed.

Cyanine dyes attenuate cerebral ischemia and reperfusion injury in rats.

Some photosensitizing cyanine dyes act on the immune system to enhance the phagocytic capacity of macrophages. In this study, we examined whether these dyes have neurotrophin-like activities and neuroprotective effects in vitro and in vivo. By screening more than 250 cyanine dyes, we found that NK-4 and NK-150, which belong to a group of pentamethine trinuclear cyanine dyes, significantly potentiated nerve growth factor (NGF)-primed neurite outgrowth of PC12HS cells in nanomolar to micromolar concentrations. Both NK-4 and NK-150 showed a remarkable hydroxyl radical-scavenging activity using an in vitro electron spin resonance (ESR)-based technique. They also effectively scavenged peroxy radicals, and in addition, NK-4 acted on superoxides to a similar extent as ascorbate. In vivo, NK-4 and NK-150 prevented cerebral ischemic injury induced by 2 h middle cerebral artery occlusion (MCAO) and 24 h reperfusion in rats. Dyes were intravenously administrated twice 1 h after the occlusion and immediately after the start of reperfusion. NK-4 and NK-150 (100 µg/kg) reduced cerebral infarct volumes by 57.0% and 46.0%, respectively. Those dyes also decreased brain swelling in the ischemic semispheres. As a result, administration of NK-4 and NK-150 provided substantial improvements in MCAO-induced neurological deficits in a dose-dependent manner. These results suggest that NK-4 and NK-150 effectively prevented ischemia-induced brain injury through their potent neurotrophin-like activity as well as antioxidative activity.