Improved tolerability of neratinib in patients with HER2-positive early-stage breast cancer: the CONTROL trial

BACKGROUND

Neratinib is an irreversible pan-HER tyrosine kinase inhibitor approved for extended adjuvant treatment in early-stage HER2-positive breast cancer based on the phase III ExteNET study. In that trial, in which no antidiarrheal prophylaxis was mandated, grade 3 diarrhea was observed in 40% of patients and 17% discontinued due to diarrhea. The international, open-label, sequential-cohort, phase II CONTROL study is investigating several strategies to improve tolerability.

PATIENTS AND METHODS

Patients who completed trastuzumab-based adjuvant therapy received neratinib 240 mg/day for 1 year plus loperamide prophylaxis (days 1-28 or 1-56). Sequential cohorts evaluated additional budesonide or colestipol prophylaxis (days 1-28) and neratinib dose escalation (DE; ongoing). The primary end point was the incidence of grade ≥3 diarrhea.

RESULTS

Final data for loperamide (L; n = 137), budesonide + loperamide (BL; n = 64), colestipol + loperamide (CL; n = 136), and colestipol + as-needed loperamide (CL-PRN; n = 104) cohorts, and interim data for DE (n = 60; completed ≥six cycles or discontinued; median duration 11 months) are available. No grade 4 diarrhea was observed. Grade 3 diarrhea rates were lower than ExteNET in all cohorts and lowest in DE (L 31%, BL 28%, CL 21%, CL-PRN 32%, DE 15%). Median number of grade 3 diarrhea episodes was one; median duration per grade 3 episode was 1.0-2.0 days across cohorts. Most grade 3 diarrhea and diarrhea-related discontinuations occurred in month 1. Diarrhea-related discontinuations were lowest in DE (L 20%, BL 8%, CL 4%, CL-PRN 8%, DE 3%). Decreases in health-related quality of life did not cross the clinically important threshold.

CONCLUSIONS

Neratinib tolerability was improved with preemptive prophylaxis or DE, which reduced the rate, severity, and duration of neratinib-associated grade ≥3 diarrhea compared with ExteNET. Lower diarrhea-related treatment discontinuations in multiple cohorts indicate that proactive management can allow patients to stay on neratinib for the recommended time period. CLINICALTRIALS.GOV: NCT02400476.

Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry

Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291.

An open-label study of chronic polyethylene glycol laxative use in chronic constipation

BACKGROUND

Polyethylene glycol 3350 (MiraLAX, Braintree Laboratories Inc., Braintree, MA, USA) is approved for the short-term treatment of occasional constipation.

AIM

To extend the safety data of polyethylene glycol used for chronic treatment of chronic constipation.

METHODS

Study subjects who met defined criteria for chronic constipation were enrolled in this open-labelled, single-treatment multi-centre study to receive polyethylene glycol laxative as a single daily dose of 17 g for 12 months. Subjects returned to their study centres after 2, 4, 6, 9 and 12 months of treatment where blood and urine samples were collected and adverse events were reviewed. At each visit, subjects were queried for ROME constipation criteria and they rated their overall improvement using a global efficacy scale.

RESULTS

311 patients including 117, age 65 and older, were enrolled and received treatment at one of 50 centres. One hundred and eighty-four completed all 12 months of treatment. With respect to the 'Global Efficacy Assessment', depending on the month of observation, 80-88% of enrolled patients, and 84-94% of the elderly, were treated successfully. Similar results were obtained from secondary efficacy measures that assessed individual ROME constipation criteria at each visit. The response to treatment was durable over time. Over the 1-year course of study representing 218 patient-years at the labelled dose, medication-associated adverse effects were gastrointestinal complaints of diarrhoea, loose stool, flatulence and nausea. These effects were generally mild or moderate in severity. There were no clinically significant changes in haematology or blood chemistry, particularly electrolytes, for the study population as a whole or the elderly group.

CONCLUSIONS

Polyethylene glycol laxative is safe and effective for treating constipation in adult and elderly patients for periods up to 12 months, with no evidence of tachyphylaxis.