First-in class selective AXL inhibitor bemcentinib (BGB324) in combination with LDAC or decitabine exerts anti-leukaemic activity in AML patients unfit for intensive chemotherapy: Phase II open-label study

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Background: The RTK AXL represents a therapeutic target promoting AML cell proliferation and survival by pleiotropic mechanisms and is a negative regulator of anti-tumour immunity. Bemcentinib is a first-in-class, highly selective, oral AXL inhibitor that has previously shown encouraging anti-leukaemic activity as a monotherapy in r/r AML and hr-MDS. Methods: A monotherapy dose-escalation and expansion part of this trial is complete. In this second, phase II part of the study, 11 and 15 AML pts unfit for intensive chemotherapy received bemcentinib at RP2D (200 mg po/d) in combination with low-dose cytarabine (LDAC) and decitabine, respectively. Median age was 77 yr (range: 50-83), median screen myeloblast count 39% (3-95%) and 2/19 (11%) of pts evaluable for FLT3 were FLT3+. Plasma protein biomarker levels were measured using the DiscoveryMap v3.3 panel (Myriad RBM) at screen and following treatment. Results: The most common TRAEs (≥ 15% of pts) were ECG QT prolongation (35%) and diarrhoea (15%). Among these, 3 were Grade 3, and none 4 or 5. All TRAEs were manageable and/or reversible. As of Feb ‘19, 9 pts (2 de novo, 1 secondary, 6 r/r) in the bemcentinib + LDAC group were evaluable for response and 4 (44%; 2 de novo + 2 relapsed) achieved rapid CRi at C2D1. Responses were durable (range: 7 – 11 cycles) in 3 of the 4 responders. A further 2 pts (22%, 1 secondary + 1 relapsed) achieved durable SD (5 and 6 cycles). mPFS among the 5 pts with durable CRi or SD was 5 months (range: 3.5-7.7). Further, at the time of writing, 11 pts (8 de novo, 3 r/r) in the bemcentinib + decitabine group were evaluable for response of which 4 (36%, all de novo) achieved CRi after ≥ 4 cycles. One additional de novo pt achieved durable SD lasting for 5 cycles. Conclusions: Bemcentinib in combination with LDAC exerted early durable responses in patients with both de novo and relapsed AML whilst the combination of bemcentinib + decitabine exerted comparably fewer and later responses in de novo AML. Soluble biomarker correlations will be presented at the meeting. Both combinations were generally well-tolerated and further exploration is warranted. Clinical trial information: NCT02488408.

A phase II study of bemcentinib (BGB324), a first-in-class highly selective AXL inhibitor, with pembrolizumab in pts with advanced NSCLC: OS for stage I and preliminary stage II efficacy

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Background: AXL is an RTK implicated in epithelial-to-mesenchymal transition and as a resistance mechanism to multiple therapies including anti-PD1. Bemcentinib (BGB324) is a first-in-class, oral, highly selective and potent AXL inhibitor which has been demonstrated to enhance anti-PD1 therapy in the pre-clinical setting. Methods: This is a Phase II single-arm, two-Stage study with bemcentinib (200mg/d) and pembrolizumab (200 mg/q3wk) for previously treated, IO naïve pts (n = 48 in total) with Stage IV lung adenocarcinoma. The primary endpoint was ORR according to RECIST 1.1 with pre-defined minimum requirement for 18% RR in the first Stage (n = 24) to proceed to Stage 2. Secondary endpoints included DCR, PFS, OS and safety. Tumour biopsies were analysed for PD-L1 (22C3 pharmDx), AXL, and infiltrating immune cells. Results: Stage 1 completed enrolment in Apr ‘18. As of Feb ‘19, 38 pts (24 and 14 in Stage 1 and 2, respectively) have been dosed with the combination; median age 66 (range 39-79) yr, 59% male, all previously received one prior line of platinum-based chemotherapy or a licensed EGFR/ALK-directed therapy. The most common TRAEs (occurring in > 15% of pts) were transaminase increases (37%), diarrhoea (29%), and asthenia (17%). All cases of transaminase increase were reversible and resolved with concomitant administration of systemic corticosteroids and interruption of study treatments. At time of writing, Stage 1 had met the efficacy threshold to proceed to Stage 2 with continued enrolment. Among 29 pts evaluable for response 7 PRs were reported (24%). For AXL positive pts (10/21 with available biopsies), ORR was 40%. PD-L1 status was known for 5 responders: 4 pts (80%) were PD-L1 negative or weakly positive. In Stage 1, mPFS was 4.0 months (95% CI 1.9 – NR) and 5.9 months in AXL positive pts (n = 10; 3.0 - NR). mOS was not mature. Conclusions: Overall, bemcentinib in combination with pembrolizumab was well tolerated and promising clinical activity was seen, particularly in pts with AXL positive disease. Updated results will be reported at the meeting, incl 12-month OS for Stage 1 and preliminary efficacy of Stage 2. Clinical trial information: NCT03184571.

The influence of cholecystokinin on gastric myoelectrical activity in duodenal ulcer following Helicobacter pylori eradication--an electrogastrographic study

Cholecystokinin (CCK) plays an important role in the regulation of postprandial gastric motor activity which was found to be abnormal in duodenal ulcer patients. This study was designed to compare the influence of CCK on gastric myoelectrical function in duodenal ulcer patients and healthy controls. Fifteen patients with active duodenal ulcer and Helicobacterpylori (H. pylori) infection and 15 healthy controls were included into this study. Electrogastrography (EGG) was performed before and 4 weeks after the eradication of H. pylori in ulcer patients and in healthy controls. We compared EGG parameters in the fasting and postprandial period and during intravenous infusion of caerulein, an analog of CCK with or without addition of loxiglumide, a specific CCK-1 receptor antagonist. The amplitude of fasting EGG in duodenal ulcer patients was similar to that in control subjects and was not affected by H. pylori eradication. In contrast, the amplitude of postprandial EGG was markedly increased in duodenal ulcer patients when compared to that in healthy controls and it was significantly reduced following the eradication of H. pylori. The blockade of CCK-1 receptors with loxiglumide in healthy controls or H. pylori eradicated ulcer patients significantly enhanced postprandial EGG amplitude almost to the level observed in the infected duodenal ulcer patients, but failed to affect this amplitude in ulcer patients. Exogenous caerulein, an analog of CCK, failed to affect EGG amplitude in duodenal ulcer patients with H. pylori infection, but it reduced significantly EGG amplitude in these patients after H. pylori eradication and in control subjects. This inhibitory effect of caerulein in H. pylori negative ulcer patients and healthy controls was abolished by the addition of loxiglumide. Ulcer patients showed significant dysrhythmia with tachygastria up to 20% of the recording time both under basal conditions and postprandially and H. pylori eradication was followed by a significant decrease in tachygastria to about 5%, the value being similar to that in healthy controls. We conclude that the amplitude and frequency of gastric myoelectrical activity are enhanced in duodenal ulcer patients and impaired in response to CCK but these changes can be normalized by successful H. pylori eradication.

[Manometric evaluation of disorders in oral and pharyngeal phases of swallowing in patients after partial laryngectomy for localized supraglottic cancer]

Manometric examinations of swallowing were conducted on 81 patients after partial laryngectomy and on 35 subjects being a control group. Resection of piriform recess, a part of the base of the tongue, the hyoid bone or its part is the factor that causes intensified difficulty during swallowing and increase in the frequency of the occurrence of aspiration. The results of manometric examinations indicate that the shape and mobility of the tongue and the mobility of remaining after the surgery parts of the larynx have the greatest influence on the efficient swallowing in patients who have undergone partial laryngectomy due to cancer initially located in the supraglottic area. The larynx mobility is closely related to the remaining of the hyoid bone. The importance of remaining the possibly non-deformed structure and mobility of the tongue during partial laryngectomy involves the issue of reconstruction of defects occurred during the surgery. Manometric examinations confirm the effectiveness of the method involving reconstruction of defects in a part of the base of the tongue with a vascular pedicle flap of the submandibular gland.

Leptin, gastrointestinal and stress hormones in response to exercise in fasted or fed subjects and before or after blood donation

Leptin, an ob gene product of adipocytes, plays a key role in the control of food intake and energy expenditure but little is known about leptin response to strenuous exercise in fasted and fed subjects or before and after blood donation. This study was designed to determine the immediate effects of strenuous exercise in healthy volunteers under fasting or fed conditions and before and one day after blood donation (450 ml) on plasma levels of leptin and gut hormones [gastrin, cholecystokinin (CCK), pancreatic polypeptide (PP) and insulin], as well as on "stress" hormones (cortisol, catecholamines and growth hormone. Two groups (A and B) of healthy non-smoking male volunteers were studied. All subjects performed incremental exercise tests until exhaustion (up to maximal oxygen uptake--VO2max), followed by 2 h of rest session. Group A perfomed the tests on a treadmill, while group B on a cycloergometer. In group A, one exercise was performed under fasting conditions and the second following ingestion of a standard liquid meal. In group B, one exercise test was performed as a control test and the second 24 h after blood donation (450 ml). Blood samples were withdrawn 5 min before the start of the test, at the VO2max, and 2 h after finishing the exercise. No significant change in plasma teptin were observed both immediately and 2 h after the exercise in fasted subjects, but after the meal the plasma leptin at VO2max and 2 h after the test was significantly higher, while after blood donation was significantly reduced. The postprandial rise in plasma leptin was accompanied by a marked increment in gut hormones; gastrin, CCK and PP and stress hormones such as norepinephrine, cortisol and GH. These hormonal changes could contribute to the postprandial rise in plasma leptin concentrations, while the fall of leptin after blood donation could be attributed to the inadequate response of stress hormones and autonomic nervous system to exhausting exercise. We conclude that strenuous physical exercise; 1) fails to affect plasma leptin level but when performed after meal but not after blood withdrawal it results in an increase and fall in plasma leptin, and 2) the release of gut hormones (gastrin, CCK and PP) and stress hormones (norepinephrine, cortisol, GH) increase immediately after exercise independently of feeding or blood donation and 3) following blood donation the strenuous exercise resulted in a marked reduction in the plasma leptin, cortisol and GH concentrations, possibly due to the impairment in the autonomic nervous control of these hormones.

[Manometric analysis of the oral and pharyngeal phases of the act of swallowing]

Manometric analysis of swallowing was conducted on 35 subjects, aged 44 to 60. The course of physiological changes in pressure during oral and pharyngeal phase of swallowing was analysed. To objectify the evaluation of analysed phenomena, parameters that include both pressure values inside pharynx and oesophagus and time dependences connected with changes in their value were used as proposed by the authors of this paper and as applied by other authors involved with these issues.

Gastric electromechanical dysfunction in Parkinson's disease

This study was designed to evaluate gastric myoelectrical and mechanical activities in idiopathic Parkinson's disease (IPD) patients. Twenty patients with IPD (14 male and 6 female, mean age 42 +/- 9 years) were studied. Patients were divided into two groups: group A--early stage of disease (no. = 6) and group B--advanced IPD (no. = 14). Electrogastrography (EGG) was performed in fasting and postprandial conditions (Synectics system). The cross-sectional area of the gastric antrum was measured by sonography (Hitachi EUB-240). The antral area in fasting conditions was 2.1 +/- 0.4 and 4.2 +/- 1.2 cm2 and gastric emptying was 75 +/- 5 and 125 +/- 12 min in groups A and B respectively. EGG showed dysrhythmias (range 1-6 cycles per minute) in about 75% of both groups of IPD patients without increase in signal amplitude after a meal. Our results suggest that gastric motility is particularly impaired in patients with advanced IPD. It may be caused by the primary degenerative process in the autonomic nervous system of the gut.

Dysfunction in gastric myoelectric and motor activity in Helicobacter pylori positive gastritis patients with non-ulcer dyspesia

Helicobacter pylori (Hp) infection has been shown to affect gastric acid secretion and the somatostatin-gastrin ratio but its effects on gastric motility have not been evaluated. This study was carried out in 12 patients (10 males and 2 females, mean age 33 +/- 6 yrs) who underwent endoscopy and Campylobacter-like Organism (CLO)-test. All patients were found initially to be Hp positive according to CLO-test. Gastric emptying was evaluated by measuring antral diameter with ultrasonography (Hitachi EUB 240) in fasted and fed patients. Electrogastrography (EGG) with antral manometry were done 5 h before and 4 h after a meal before the therapy and one month after the eradication with triple therapy (lanzoprazole 30 mg daily- 2 x 250 mg clarithromycin 500 mg t.i.d.-3 x 500 mg and metronidazole 500 mg b.i.d.-2 x 500 mg). In Hp positive patients before the triple therapy the mean fasted antral diameter was 4.3 cm2, initial EGG showed significant dysrhythmia of electrical control activity (ECA) with tachygastria up to 25% of recording time in 9 of 12 Hp positive patients without normal increase of the power of signal in any of tested subjects. In 7 Hp positive fasted antral manometry failed to exhibit gastric phases III of the migrating motor complex (MMC). Hp eradication was accomplished in 10 of 12 examined patients and this was followed by a decrease in tachygastria to 3 cpm rhythm with an increase of the ECA power after meal. Phase III of MMC was observed again in 7 Hp negative patients with a decrease of fasted antral diameter (p < 0.05). Fasted and fed antral motility pattern increased after eradication. Two patients remained Hp positive after standard therapy. We conclude that most symptomatic non ulcer dyspeptic Hp positive patients show changes in ECA and antral hypomotility that are associated with Hp infections.

Double-blind crossover study of ranitidine and ebrotidine in gastro-esophageal reflux disease

Gastroesophageal reflux disease (GERD) is multifactorial disorder in which acid exposure has a central role in the mucosal damage, and the mainstay of medical treatment is the suppression of gastric acid secretion justifying the use of H2 receptors antagonists. In our study we compared the effects of ranitidine and ebrotidine, a novel H2 antagonist with gastroprotective properties, on the motor, pH and endoscopic aspects of GERD in randomized cross-over trial in humans. Twenty patients with endoscopic evidence of erosive esophagitis were included in the study. Esophageal manometry and 24-hour pH-metry were done with the use Synectics (Sweden) systems. The same examinations were repeated after 20 days period of treatment with either ranitidine or ebrotidine, given in single dose 300 and 800 mg (nocte) respectively. The pressure within the lower esophageal sphincter (LES) in the untreated and treated with ebrotidine or ranitidine patients remained lowered. Patients with GERD showed increase in duration and decrease in amplitude and propagation of peristaltic waves in the esophageal body which were not improved after treatment. Complete healing after 40 days of treatment was comparable with ebrotidine and ranitidine and averaged about 40%. The pH-metry showed improvement in treated patients in the reflux frequency and time pH below 4, ranitidine being more effective than ebrotidine. It can be concluded that GERD patients showed weaker primary peristalsis unrelated to LES pressure and treatment. Treatment with ebrotidine or ranitidine reduced significantly the endoscopic and self-assessment score, ebrotidine and ranitidine being equally effective in healing of esophageal mucosal lesions.

Nitric oxide inhibits the myoelectric activity of the small intestine in dogs

Intestinal motility in fasted animals shows cyclic changes (MMC) that are interrupted by feeding. The aim of this study was to determine the possible implication of nitric oxide (NO) (that was proposed as nonadrenergic noncholinergic neurotransmitter) in the motor components of MMC in 5 conscious dogs equipped with monopolar electrodes implanted along the small bowel. In fasted dogs with typical MMCs, L-NNA (an inhibitor of NO synthase) (5 mg/kg-h i.v.) decreased the MMC interval from control 80 +/- 7 to 60 +/- 4 min and increased significantly the spike activity. Infusion of L-arginine (L-Arg) (a substrate of NO synthase) (10 mg/kg-h i.v.) increased the MMC interval from control 79 +/- 7 to 96 +/- 8 min and reduced the slow waves with spikes by about 25%. Similar but transient effects were observed when glycerin trinitrate (GTN) (a donor of NO) (1 mg/kg-h) was administered. After ingestion of meal, the MMC cycles were replaced by irregular spike activity with an average of about 35% slow waves with spikes. Infusion of L-Arg (10 mg/kg-h) reduced by about 90% the postprandial spike activity. Also, infusion of GTN (1 mg/kg-h) strongly reduced the postprandial spike activity. L-NNA in fed dogs caused an initial increase in spike activity followed by phase III-like activity. Similar effects were obtained when L-NNA was infused in dogs with fed-like motility patterns induced by i.v. infusion of caerulein (75 pmol/kg-h). L-NNA added to L-Arg infusion reversed in part the changes of intestinal motility patterns induced by L-Arg. We conclude that NO system exerts a tonic inhibitory influence on intestinal myoelectric activity by reducing the frequency of MMC pacesetter and by suppressing the postprandial spike activity.