First-In-Human Phase I Study of Tinengotinib (TT-00420), a Multiple Kinase Inhibitor, as a Single Agent in Patients With Advanced Solid Tumors.

PURPOSE: This first-in-human phase I dose-escalation study evaluated the safety, pharmacokinetics, and efficacy of tinengotinib (TT-00420), a multi-kinase inhibitor targeting fibroblast growth factor receptors 1-3 (FGFRs 1-3), Janus kinase 1/2, vascular endothelial growth factor receptors, and Aurora A/B, in patients with advanced solid tumors. PATIENTS AND METHODS: Patients received tinengotinib orally daily in 28-day cycles. Dose escalation was guided by Bayesian modeling using escalation with overdose control. The primary objective was to assess dose-limiting toxicities (DLTs), maximum tolerated dose (MTD), and dose recommended for dose expansion (DRDE). Secondary objectives included pharmacokinetics and efficacy. RESULTS: Forty-eight patients were enrolled (dose escalation, n = 40; dose expansion, n = 8). MTD was not reached; DRDE was 12 mg daily. DLTs were palmar-plantar erythrodysesthesia syndrome (8 mg, n = 1) and hypertension (15 mg, n = 2). The most common treatment-related adverse event was hypertension (50.0%). In 43 response-evaluable patients, 13 (30.2%) achieved partial response (PR; n = 7) or stable disease (SD) ≥ 24 weeks (n = 6), including 4/11 (36.4%) with FGFR2 mutations/fusions and cholangiocarcinoma (PR n = 3; SD ≥ 24 weeks n = 1), 3/3 (100.0%) with hormone receptor (HR)-positive/HER2-negative breast cancer (PR n = 2; SD ≥ 24 weeks n = 1), 2/5 (40.0%) with triple-negative breast cancer (TNBC; PR n = 1; SD ≥ 24 weeks n = 1), and 1/1 (100.0%) with castrate-resistant prostate cancer (CRPC; PR). Four of 12 patients (33.3%; HR-positive/HER2-negative breast cancer, TNBC, prostate cancer, and cholangiocarcinoma) treated at DRDE had PRs. Tinengotinib's half-life was 28-34 hours. CONCLUSIONS: Tinengotinib was well tolerated with favorable pharmacokinetic characteristics. Preliminary findings indicated potential clinical benefit in FGFR inhibitor-refractory cholangiocarcinoma, HER2-negative breast cancer (including TNBC), and CRPC. Continued evaluation of tinengotinib is warranted in phase II trials.

Durvalumab alone and durvalumab plus tremelimumab versus chemotherapy in previously untreated patients with unresectable, locally advanced or metastatic urothelial carcinoma (DANUBE): a randomised, open-label, multicentre, phase 3 trial.

BACKGROUND: Survival outcomes are poor for patients with metastatic urothelial carcinoma who receive standard, first-line, platinum-based chemotherapy. We assessed the overall survival of patients who received durvalumab (a PD-L1 inhibitor), with or without tremelimumab (a CTLA-4 inhibitor), as a first-line treatment for metastatic urothelial carcinoma. METHODS: DANUBE is an open-label, randomised, controlled, phase 3 trial in patients with untreated, unresectable, locally advanced or metastatic urothelial carcinoma, conducted at 224 academic research centres, hospitals, and oncology clinics in 23 countries. Eligible patients were aged 18 years or older with an Eastern Cooperative Oncology Group performance status of 0 or 1. We randomly assigned patients (1:1:1) to receive durvalumab monotherapy (1500 mg) administered intravenously every 4 weeks; durvalumab (1500 mg) plus tremelimumab (75 mg) administered intravenously every 4 weeks for up to four doses, followed by durvalumab maintenance (1500 mg) every 4 weeks; or standard-of-care chemotherapy (gemcitabine plus cisplatin or gemcitabine plus carboplatin, depending on cisplatin eligibility) administered intravenously for up to six cycles. Randomisation was done through an interactive voice-web response system, with stratification by cisplatin eligibility, PD-L1 status, and presence or absence of liver metastases, lung metastases, or both. The coprimary endpoints were overall survival compared between the durvalumab monotherapy versus chemotherapy groups in the population of patients with high PD-L1 expression (the high PD-L1 population) and between the durvalumab plus tremelimumab versus chemotherapy groups in the intention-to-treat population (all randomly assigned patients). The study has completed enrolment and the final analysis of overall survival is reported. The trial is registered with ClinicalTrials.gov, NCT02516241, and the EU Clinical Trials Register, EudraCT number 2015-001633-24. FINDINGS: Between Nov 24, 2015, and March 21, 2017, we randomly assigned 1032 patients to receive durvalumab (n=346), durvalumab plus tremelimumab (n=342), or chemotherapy (n=344). At data cutoff (Jan 27, 2020), median follow-up for survival was 41·2 months (IQR 37·9-43·2) for all patients. In the high PD-L1 population, median overall survival was 14·4 months (95% CI 10·4-17·3) in the durvalumab monotherapy group (n=209) versus 12·1 months (10·4-15·0) in the chemotherapy group (n=207; hazard ratio 0·89, 95% CI 0·71-1·11; p=0·30). In the intention-to-treat population, median overall survival was 15·1 months (13·1-18·0) in the durvalumab plus tremelimumab group versus 12·1 months (10·9-14·0) in the chemotherapy group (0·85, 95% CI 0·72-1·02; p=0·075). In the safety population, grade 3 or 4 treatment-related adverse events occurred in 47 (14%) of 345 patients in the durvalumab group, 93 (27%) of 340 patients in the durvalumab plus tremelimumab group, and in 188 (60%) of 313 patients in the chemotherapy group. The most common grade 3 or 4 treatment-related adverse event was increased lipase in the durvalumab group (seven [2%] of 345 patients) and in the durvalumab plus tremelimumab group (16 [5%] of 340 patients), and neutropenia in the chemotherapy group (66 [21%] of 313 patients). Serious treatment-related adverse events occurred in 30 (9%) of 345 patients in the durvalumab group, 78 (23%) of 340 patients in the durvalumab plus tremelimumab group, and 50 (16%) of 313 patients in the chemotherapy group. Deaths due to study drug toxicity were reported in two (1%) patients in the durvalumab group (acute hepatic failure and hepatitis), two (1%) patients in the durvalumab plus tremelimumab group (septic shock and pneumonitis), and one (<1%) patient in the chemotherapy group (acute kidney injury). INTERPRETATION: This study did not meet either of its coprimary endpoints. Further research to identify the patients with previously untreated metastatic urothelial carcinoma who benefit from treatment with immune checkpoint inhibitors, either alone or in combination regimens, is warranted. FUNDING: AstraZeneca.

Progressive resistance training for adolescents with cerebral palsy: the STAR randomized controlled trial.

AIM: To evaluate the effect of progressive resistance training of the ankle plantarflexors on gait efficiency, activity, and participation in adolescents with cerebral palsy (CP). METHOD: Sixty-four adolescents (10-19y; 27 females, 37 males; Gross Motor Function Classification System [GMFCS] levels I-III) were randomized to 30 sessions of resistance training (10 supervised and 20 unsupervised home sessions) over 10 weeks or usual care. The primary outcome was gait efficiency indicated by net nondimensional oxygen cost (NNcost). Secondary outcomes included physical activity, gross motor function, participation, muscle strength, muscle and tendon size, and muscle and tendon stiffness. Analysis was intention-to-treat. RESULTS: Median attendance at the 10 supervised sessions was 80% (range 40-100%). There was no between-group difference in NNcost at 10 (mean difference: 0.02, 95% confidence interval [CI] -0.07 to 0.11, p=0.696) or 22 weeks (mean difference: -0.08, 95% CI -0.18 to 0.03, p=0.158). There was also no evidence of between-group differences in secondary outcomes at 10 or 22 weeks. There were 123 adverse events reported by 27 participants in the resistance training group. INTERPRETATION: We found that 10 supervised sessions and 20 home sessions of progressive resistance training of the ankle plantarflexors did not improve gait efficiency, muscle strength, activity, participation, or any biomechanical outcome among adolescents with CP. WHAT THIS PAPER ADDS: Thirty sessions of progressive resistance training of the ankle plantarflexors over 10 weeks did not improve gait efficiency among ambulatory adolescents with cerebral palsy. Resistance training did not improve muscle strength, activity, or participation. Ninety percent of participants experienced an adverse event. Most adverse events were expected and no serious adverse events were reported.

The use and perception of support walkers for children with disabilities: a United Kingdom survey.

BACKGROUND: Support walkers are a type of assistive device that may enable non-ambulant children with disabilities to walk independently and promote improvements in bowel function, bone mineral density (BMD), mobility, independence, participation and social function. However, there is little evidence to support these benefits and there is a lack of research describing the use of support walkers in clinical practice. This study aimed to examine the use of support walkers for children with disabilities in clinical practice. METHOD: A survey was distributed via professional organisations, charities and schools associated with paediatric disabilities in the UK. Participants were recruited between January and March 2018. Populations of interest were those who prescribe support walkers to children with disabilities and those who work with children who use them. RESULTS: In total, 125 people were included in the analysis; 107 responders prescribed support walkers and 18 responders worked with children who used support walkers. The population of children who use support walkers ranged from 6 months to 18 years and included children with cerebral palsy, chromosomal abnormalities and other medical conditions. Use of these devices was also reported in schools, at home and in the community for varying lengths of time. Numerous perceived benefits were noted, most frequent of which were increases in physical activity and enjoyment. By comparison, fewer perceived problems were identified but centred on lack of space and difficulty with transfers. CONCLUSIONS: This study provides insight into the use of support walkers in the UK, particularly surrounding current practices, which may help to improve consistency in clinical settings. Perceived benefits and problems may provide a basis for identification of appropriate outcome measures to monitor effectiveness. These results should also provide a basis for designing future studies to examine effectiveness of support walkers for paediatric disabilities.

Interventions to Improve or Maintain Lower-Limb Function Among Ambulatory Adolescents with Cerebral Palsy: A Cross-Sectional Survey of Current Practice in the UK.

OBJECTIVES: To describe physiotherapy management to improve or maintain lower-limb function among adolescents with cerebral palsy, classified in Gross Motor Function Classification System levels I-III, in the United Kingdom (UK). METHODS: A list of interventions was identified using a nominal group technique and developed into a survey, which was distributed to approximately 2,100 pediatric physiotherapists in the UK through the Association of Pediatric Chartered Physiotherapists and a private physiotherapy clinic in London between April and June 2015. One-hundred and thirty-five physiotherapists completed the survey. Survey respondents indicated how frequently they used each intervention (i.e., "frequently," "sometimes," "rarely," and "never") in the past year. RESULTS: Provision of explanations to the child, liaison with families, liaison with health professionals, provision of advice to schools, and stretching were the most frequently used interventions with 90%, 90%, 86%, 79%, and 76% of respondents, respectively, reporting that they frequently used each. The interventions most commonly reported as "never" used were conductive education (88%), MOVE programme (85%), functional electrical stimulation (82%), body-weight supported treadmill training (80%), and rebound therapy (71%). CONCLUSIONS: This study suggests that a large number of interventions are used by physiotherapists in the United Kingdom to improve or maintain lower-limb function among adolescents with CP, not all of which are evidence-based.

Phase 1, open-label, dose escalation, safety, and pharmacokinetics study of ME-344 as a single agent in patients with refractory solid tumors.

BACKGROUND: The current phase 1, open-label, dose escalation study was conducted to establish the safety, tolerability, pharmacokinetic profile, and preliminary antitumor activity of the novel mitochondrial inhibitor ME-344 in patients with refractory solid tumors. METHODS: Patients with refractory solid tumors were treated in a 3 + 3 dose escalation design. ME-344 was administered via intravenous infusion on days 1, 8, and 15 of the first 28-day cycle and weekly thereafter. Pharmacokinetics was assessed on days 1 and 15 of the first cycle. RESULTS: A total of 30 patients (median age, 65 years; 67% of whom were female) received ME-344. There were 5 dose-limiting toxicities reported. Four patients developed grade 3 neuropathy (2 patients each at doses of 15 mg/kg and 20 mg/kg) and 1 patient treated at a dose of 10 mg/kg developed a grade 3 acute myocardial infarction (toxicity was graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 4.03]). The maximum tolerated dose (MTD) was defined as 10 mg/kg weekly. The most common adverse events were nausea, dizziness, and fatigue. At the MTD of 10 mg/kg, the maximal plasma concentration (Cmax) was 25.8 µg/mL and the area under the concentration curve from time zero to infinity was 25.9 hour*µg/mL. One patient with small cell lung cancer achieved a partial response for ≥ 52 weeks. Four patients had prolonged stable disease (1 patient each with urothelial carcinoma [47 weeks], carcinoid tumor [≥ 40 weeks], cervical leiomyosarcoma [39 weeks], and cervical cancer [≥ 31 weeks]). CONCLUSIONS: The once-weekly administration of ME-344 was generally well tolerated in the current study, a first-in-human study; dose-limiting neuropathy was noted, but not at the MTD. Exposures at the 10-mg/kg dose level suggest a sufficient therapeutic index. The preliminary clinical activity as a monotherapy supports the further clinical development of ME-344 in combination with chemotherapy.

Acceptability of a progressive resistance training programme for ambulatory adolescents with spastic cerebral palsy in England: a qualitative study.

PURPOSE: The aim of this study was to explore the acceptability of a 10-week progressive resistance training programme from the perspective of ambulatory adolescents with CP and physiotherapists. MATERIAL AND METHODS: Semi-structured interviews were conducted with 32 adolescents with spastic CP, aged 10-19 years in Gross Motor Function Classification System (GMFCS) levels I-III, and 13 physiotherapists. Adolescents had completed a 10-week progressive resistance training programme and physiotherapists had delivered the programme. The Framework Method was used to analyse data. RESULTS: The analysis identified four themes. "It's do-able" described the acceptability of the programme structure, including the frequency of sessions and the duration of the programme. "They were difficult but I did it" described the acceptability of the exercises. "It is completely different," explored the experience of using equipment to progress the programme and "I wish I could do it on a permanent basis" discussed continuing to participate in resistance training. CONCLUSIONS: Findings suggest that resistance training is largely acceptable to adolescents and physiotherapists. Acceptability was enhanced by having a weekly supervised session and being able to adapt and progress the exercises to meet the individual's ability. However, there are challenges to implementing progressive resistance training as part of routine practice.Clinical trial registration number: ISRCTN90378161.

Progressive resistance training is largely acceptable to ambulatory adolescents with cerebral palsy and physiotherapists.Adolescents' ability to complete the exercises increased their confidence and motivated them to continue with the programme.Adolescents valued being supervised by a physiotherapist and believed they needed a physiotherapist to progress the exercises and motivate them to perform to their maximum capacity.Within the National Health Service (NHS), limited time and equipment may prevent implementation of resistance training for adolescents with CP in accordance with guidelines.A short-term resistance training programme delivered by physiotherapists in the NHS may provide the foundation for continuing participation in resistance training in a community setting.

Validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy: A cross-sectional study.

OBJECTIVES: The aim of this study was to examine the validity of the International Physical Activity Questionnaire Short Form (IPAQ-SF) as a measure of physical activity (PA) in young people with cerebral palsy (CP). DESIGN: Cross-sectional. SETTING: Participants were recruited through 8 National Health Service (NHS) trusts, one school, one university and through organisations that provide services for people with disabilities in England. PARTICIPANTS: Sixty-four, ambulatory young people aged 10-19 years with CP [Gross Motor Function Classification System (GMFCS) levels I-III] participated in this study. MAIN OUTCOME MEASURE: The IPAQ-SF was administered to participants. Participants were then asked to wear a wGT3X-BT triaxial accelerometer (ActiGraph, Pensacola, FL) for 7 days to objectively assess PA. Time spent in sedentary behaviour, in moderate to vigorous PA (MVPA) and in total PA (TPA) was compared between measures. RESULTS: Young people with CP self-reported less time in sedentary behaviour and underestimated the time spent in TPA, when compared to accelerometer measurements. Bland-Altman plots demonstrated poor agreement between the measures for MVPA, with upper and lower 95% limits of agreement of -147 to 148.9minute. After adjusting for gender and GMFCS level, age was a predictor of the difference between measures for MVPA (P<0.001) and TPA (P<0.001). CONCLUSIONS: These findings suggest that the IPAQ-SF is not a valid method of measuring TPA or sedentary behaviour in young people with CP and it is not appropriate for use when assessing an individual's time in MVPA. Therefore, where feasible, an objective measure of PA should be used. CLINICAL TRIAL REGISTRATION NUMBER: ISRCTN90378161.

Predictors of Walking Efficiency in Children With Cerebral Palsy: Lower-Body Joint Angles, Moments, and Power.

BACKGROUND: People with cerebral palsy (CP) experience increased muscle stiffness, muscle weakness, and reduced joint range of motion. This can lead to an abnormal pattern of gait, which can increase the energy cost of walking and contribute to reduced participation in physical activity. OBJECTIVE: The aim of the study was to examine associations between lower-body joint angles, moments, power, and walking efficiency in adolescents with CP. DESIGN: This was a cross-sectional study. METHODS: Sixty-four adolescents aged 10 to 19 years with CP were recruited. Walking efficiency was measured as the net nondimensional oxygen cost (NNcost) during 6 minutes of overground walking at self-selected speed. Lower-body kinematics and kinetics during walking were collected with 3-dimensional motion analysis, synchronized with a treadmill with integrated force plates. The associations between the kinematics, kinetics, and NNcost were examined with multivariable linear regression. RESULTS: After adjusting for age, sex, and Gross Motor Function Classification System level, maximum knee extension angle (ß = -0.006), hip angle at midstance (ß = -0.007), and maximum hip extension (ß = -0.008) were associated with NNcost. Age was a significant modifier of the association between the NNcost and a number of kinematic variables. LIMITATIONS: This study examined kinetic and kinematic variables in the sagittal plane only. A high interindividual variation in gait pattern could have influenced the results. CONCLUSIONS: Reduced knee and hip joint extension are associated with gait inefficiency in adolescents with CP. Age is a significant factor influencing associations between ankle, knee, and hip joint kinematics and gait efficiency. Therapeutic interventions should investigate ways to increase knee and hip joint extension in adolescents with CP.

Strength Training for Adolescents with cerebral palsy (STAR): study protocol of a randomised controlled trial to determine the feasibility, acceptability and efficacy of resistance training for adolescents with cerebral palsy.

INTRODUCTION: Gait is inefficient in children with cerebral palsy, particularly as they transition to adolescence. Gait inefficiency may be associated with declines in gross motor function and participation among adolescents with cerebral palsy. Resistance training may improve gait efficiency through a number of biomechanical and neural mechanisms. The aim of the Strength Training for Adolescents with cerebral palsy (STAR) trial is to evaluate the effect of resistance training on gait efficiency, activity and participation in adolescents with cerebral palsy. We also aim to determine the biomechanical and neural adaptations that occur following resistance training and evaluate the feasibility and acceptability of such an intervention for adolescents with cerebral palsy. METHODS AND ANALYSIS: 60 adolescents (Gross Motor Function Classification System level I-III) will be randomised to a 10-week resistance training group or a usual care control group according to a computer-generated random schedule. The primary outcome is gait efficiency. Secondary outcomes are habitual physical activity, participation, muscle-tendon mechanics and gross motor function. General linear models will be used to evaluate differences in continuous data between the resistance training and usual care groups at 10 and 22 weeks, respectively. A process evaluation will be conducted alongside the intervention. Fidelity of the resistance training programme to trial protocol will be quantified by observations of exercise sessions. Semistructured interviews will be conducted with participants and physiotherapists following the resistance training programme to determine feasibility and acceptability of the programme. ETHICS AND DISSEMINATION: This trial has ethical approval from Brunel University London's Department of Clinical Sciences' Research Ethics Committee and the National Research Ethics Service (NRES) Committee London-Surrey Borders. The results of the trial will be submitted for publication in academic journals, presented at conferences and distributed to adolescents, families and healthcare professionals through the media with the assistance of the STAR advisory group. TRIAL REGISTRATION NUMBER: ISRCTN90378161; Pre-results.

A phase I study of PF-04449913, an oral hedgehog inhibitor, in patients with advanced solid tumors.

PURPOSE: To estimate the maximum tolerated dose (MTD) of single-agent PF-04449913, and to evaluate safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity in patients with advanced tumors. EXPERIMENTAL DESIGN: A 3+3 design was used in this open-label, multicenter, phase I study and dose escalation/de-escalation applied until identification of the MTD. PF-04449913 was orally administered once daily in continuous 28-day treatment cycles. The starting dose was 80 mg. RESULTS: A total of 23 patients were enrolled; 19 were evaluable for first-cycle dose-limiting toxicity (DLT). The first-cycle DLT rate at the 640 mg dose level was 33.3%, and the MTD was estimated to be 320 mg once daily. The recommended phase II dose was not determined. PF-04449913 was generally well tolerated at doses of 80 to 320 mg once daily. The most common treatment-related adverse events (AE) were grade 1-2 dysgeusia, fatigue, decreased appetite, nausea, dizziness, dehydration, and diarrhea. Treatment-related grade 3 AEs only occurred in patients receiving PF-04449913 640 mg once daily. No treatment-related grade 4-5 AEs were reported. Pharmacokinetic analysis indicated a generally dose-proportional kinetics with biphasic elimination, supporting once-daily dosing. PF-04449913 modulated hedgehog signaling at the dose levels tested, as demonstrated by >80% downregulation of GLI1 expression in the skin of treated patients. Eight patients (34.8%) achieved stable disease; none had complete or partial response. Three patients with disease progression at enrollment had prolonged disease stabilization (≥6 months). CONCLUSIONS: The results obtained in this study support further evaluation of PF-04449913 in patients with advanced solid tumors.

Treatment with PF-04449913, an oral smoothened antagonist, in patients with myeloid malignancies: a phase 1 safety and pharmacokinetics study.

BACKGROUND: Activation of the Hedgehog signalling pathway contributes to cancer progression and the development of myeloid leukaemia stem cell therapeutic resistance. We aimed to identify the maximum tolerated dose (MTD) and the recommended phase 2 dose of the selective Hedgehog antagonist PF-04449913 in myeloid malignancies. METHODS: We undertook an open-label, dose-finding, standard 3+3 design phase 1 study of PF-04449913 in adult patients with acute myeloid leukaemia, chronic myeloid leukaemia, chronic myelomonocytic leukaemia, myelodysplastic syndrome, or myelofibrosis who were refractory, resistant, or intolerant to previous treatments, at three centres in the USA and one in Italy. Patients who had newly diagnosed, untreated disease were included if they were not eligible for standard treatment options or if standard treatments were not deemed appropriate. Patients received PF-04449913 once daily continuously until disease progression, unacceptable toxic effects, or patient withdrawal for up to 12 28-day cycles. Additional cycles were given if patients showed evidence of clinical benefit. The starting dose was 5 mg and was increased by 100% until the first dose-limiting toxic effect (DLT) and by 50% thereafter, in keeping with a 3+3 clinical trial statistical design. The primary endpoint was first-cycle DLTs. Secondary endpoints were safety, tolerability, pharmacokinetics, pharmacodynamics, and preliminary clinical activity. This trial is registered with ClinicalTrials.gov, number NCT00953758. FINDINGS: Between March 24, 2010, and Sept 7, 2012, 47 patients were enrolled and included in the study: 28 with acute myeloid leukaemia, six with myelodysplastic syndrome, five with chronic myeloid leukaemia (two with chronic-phase and three with blast-phase disease), one with chronic myelomonocytic leukaemia, and seven with myelofibrosis. Patients received PF-04449913 once daily at 5 mg (n=3), 10 mg (n=3), 20 mg (n=4), 40 mg (n=4), 80 mg (n=8), 120 mg (n=3), 180 mg (n=3), 270 mg (n=5), 400 mg (n=9), and 600 mg (n=5). Two patients experienced DLTs (one each in the 80 mg and 600 mg dose groups). The MTD for PF-04449913 was established to be 400 mg once daily. Of the 47 patients enrolled, 28 (60%) experienced treatment-related adverse events, three of which were grade 4 in severity. The most common treatment-related adverse events included dysgeusia (13 [28%] patients), decreased appetite (nine [19%]), and alopecia (seven [15%]). None of the 15 deaths reported were treatment related. Pharmacokinetics seemed to be dose proportional. The mean half-life was 23·9 h (SD 14·0) in the MTD group. Some suggestion of clinical activity was noted in 23 (49%) of 47 patients with haematological malignancies. Based on these results, the recommended phase 2 dose was 200 mg or lower once daily. INTERPRETATION: Based on these findings, PF-04449913 is being tested in phase 2 studies in patients with myelodysplastic syndrome, acute myeloid leukaemia, and myelofibrosis. FUNDING: Pfizer.

Evaluation of the effect of food and ketoconazole on the pharmacokinetics of the smoothened inhibitor PF-04449913 in healthy volunteers.

PURPOSE: To evaluate the effect of a potent cytochrome P450 3A4 (CYP3A4) inhibitor, ketoconazole, and separately the effect of food on PF-04449913 pharmacokinetics in healthy volunteers. METHODS: This was an open-label, two-sequence, three-period, three-treatment, single-dose, crossover study. Subjects were randomized to receive single doses of 200 mg PF-04449913 after an overnight fast or after consuming a high-fat meal during Period 1 or 2, with a washout period of at least 8 days. In Period 3, all subjects received ketoconazole (400 mg/day) (days 1-7) and a co-administered single 200-mg PF-04449913 dose (day 4). RESULTS: Geometric mean ratio of PF-04449913 in the presence of ketoconazole versus PF-04449913 alone was 2.40 [90% confidence interval (CI) 2.15, 2.68] for area under the plasma concentration-time curve from time zero to infinity (AUC(0-inf)) and 1.40 (90% CI 1.24, 1.58) for peak plasma concentration (C max). The geometric mean ratio for fed state compared with fasted state for AUC(0-inf) was 0.87 (90% CI 0.78, 0.97) and for C max was 0.66 (90% CI 0.56, 0.78). PF-04449913 was well tolerated, and all adverse events were mild to moderate. CONCLUSIONS: PF-04449913 plasma exposures and peak concentrations were increased following concurrent administration of ketoconazole in healthy volunteers. These findings provide the upper limit for expected PF-04449913 exposures after co-administration of a strong CYP3A4 inhibitor in patients with cancer who routinely receive antifungal azoles. While a high-fat meal decreased PF-04449913 exposure, the differences in plasma exposure under the two conditions were not considered clinically meaningful.

Targeting activin receptor-like kinase 1 inhibits angiogenesis and tumorigenesis through a mechanism of action complementary to anti-VEGF therapies.

Genetic and molecular studies suggest that activin receptor-like kinase 1 (ALK1) plays an important role in vascular development, remodeling, and pathologic angiogenesis. Here we investigated the role of ALK1 in angiogenesis in the context of common proangiogenic factors [PAF; VEGF-A and basic fibroblast growth factor (bFGF)]. We observed that PAFs stimulated ALK1-mediated signaling, including Smad1/5/8 phosphorylation, nuclear translocation and Id-1 expression, cell spreading, and tubulogenesis of endothelial cells (EC). An antibody specifically targeting ALK1 (anti-ALK1) markedly inhibited these events. In mice, anti-ALK1 suppressed Matrigel angiogenesis stimulated by PAFs and inhibited xenograft tumor growth by attenuating both blood and lymphatic vessel angiogenesis. In a human melanoma model with acquired resistance to a VEGF receptor kinase inhibitor, anti-ALK1 also delayed tumor growth and disturbed vascular normalization associated with VEGF receptor inhibition. In a human/mouse chimera tumor model, targeting human ALK1 decreased human vessel density and improved antitumor efficacy when combined with bevacizumab (anti-VEGF). Antiangiogenesis and antitumor efficacy were associated with disrupted co-localization of ECs with desmin(+) perivascular cells, and reduction of blood flow primarily in large/mature vessels as assessed by contrast-enhanced ultrasonography. Thus, ALK1 may play a role in stabilizing angiogenic vessels and contribute to resistance to anti-VEGF therapies. Given our observation of its expression in the vasculature of many human tumor types and in circulating ECs from patients with advanced cancers, ALK1 blockade may represent an effective therapeutic opportunity complementary to the current antiangiogenic modalities in the clinic.