Advances in gastrointestinal pharmacotherapy

Potassium-competitive acid blockers and gastroesophageal reflux disease

Proton pump inhibitors (PPIs), the most commonly used antisecretory medi-cations in the management of reflux illness, virtually eliminate elective surgery for ulcer disease, and relegate anti-reflux surgery to patients with gastroesophageal reflux disease (GERD) who are inadequately managed by medical therapy. However, PPI medications still leave some therapeutic demands of GERD unmet. Furthermore, up to 40%-55% of daily PPI users have chronic symptoms, due to PPI refractoriness. Potassium-competitive acid blockers (P-CABs) transcend many of the problems and limits of PPIs, delivering quick, powerful, and extended acid suppression and allowing for treatment of numerous unmet needs. Recently, it has become clear that compromised mucosal integrity plays a role in the etiology of GERD. As a result, esophageal mucosal protection has emerged as a novel and potential treatment approach. An increasing body of research demonstrates that when P-CABs are used as primary drugs or add-on drugs (to regular treatment), they provide a considerable extra benefit, particularly in alleviating symptoms that do not respond to PPI therapy.

Infliximab, adalimumab and golimumab for treating moderately to severely active ulcerative colitis after the failure of conventional therapy (including a review of TA140 and TA262): clinical effectiveness systematic review and economic model

BACKGROUND

Ulcerative colitis (UC) is the most common form of inflammatory bowel disease in the UK. UC can have a considerable impact on patients' quality of life. The burden for the NHS is substantial.

OBJECTIVES

To evaluate the clinical effectiveness and safety of interventions, to evaluate the incremental cost-effectiveness of all interventions and comparators (including medical and surgical options), to estimate the expected net budget impact of each intervention, and to identify key research priorities.

DATA SOURCES

Peer-reviewed publications, European Public Assessment Reports and manufacturers' submissions. The following databases were searched from inception to December 2013 for clinical effectiveness searches and from inception to January 2014 for cost-effectiveness searches for published and unpublished research evidence: MEDLINE, EMBASE, Cumulative Index to Nursing and Allied Health Literature, The Cochrane Library including the Cochrane Systematic Reviews Database, Cochrane Controlled Trials Register, Database of Abstracts of Reviews of Effects, the Health Technology Assessment database and NHS Economic Evaluation Database; ISI Web of Science, including Science Citation Index, and the Conference Proceedings Citation Index-Science and Bioscience Information Service Previews. The US Food and Drug Administration website and the European Medicines Agency website were also searched, as were research registers, conference proceedings and key journals.

REVIEW METHODS

A systematic review [including network meta-analysis (NMA)] was conducted to evaluate the clinical effectiveness and safety of named interventions. The health economic analysis included a review of published economic evaluations and the development of a de novo model.

RESULTS

Ten randomised controlled trials were included in the systematic review. The trials suggest that adult patients receiving infliximab (IFX) [Remicade(®), Merck Sharp & Dohme Ltd (MSD)], adalimumab (ADA) (Humira(®), AbbVie) or golimumab (GOL) (Simponi(®), MSD) were more likely to achieve clinical response and remission than those receiving placebo (PBO). Hospitalisation data were limited, but suggested more favourable outcomes for ADA- and IFX-treated patients. Data on the use of surgical intervention were sparse, with a potential benefit for intervention-treated patients. Data were available from one trial to support the use of IFX in paediatric patients. Safety issues identified included serious infections, malignancies and administration site reactions. Based on the NMA, in the induction phase, all biological treatments were associated with statistically significant beneficial effects relative to PBO, with the greatest effect associated with IFX. For patients in response following induction, all treatments except ADA and GOL 100 mg at 32-52 weeks were associated with beneficial effects when compared with PBO, although these were not significant. The greatest effects at 8-32 and 32-52 weeks were associated with 100 mg of GOL and 5 mg/kg of IFX, respectively. For patients in remission following induction, all treatments except ADA at 8-32 weeks and GOL 50 mg at 32-52 weeks were associated with beneficial effects when compared with PBO, although only the effect of ADA at 32-52 weeks was significant. The greatest effects were associated with GOL (at 8-32 weeks) and ADA (at 32-52 weeks). The economic analysis suggests that colectomy is expected to dominate drug therapies, but for some patients, colectomy may not be considered acceptable. In circumstances in which only drug options are considered, IFX and GOL are expected to be ruled out because of dominance, while the incremental cost-effectiveness ratio for ADA versus conventional treatment is approximately £50,300 per QALY gained.

LIMITATIONS

The health economic model is subject to several limitations: uncertainty associated with extrapolating trial data over a lifetime horizon, the model does not consider explicit sequential pathways of non-biological treatments, and evidence relating to complications of colectomy was identified through consideration of approaches used within previous models rather than a full systematic review.

CONCLUSIONS

Adult patients receiving IFX, ADA or GOL were more likely to achieve clinical response and remission than those receiving PBO. Further data are required to conclusively demonstrate the effect of interventions on hospitalisation and surgical outcomes. The economic analysis indicates that colectomy is expected to dominate medical treatments for moderate to severe UC.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42013006883.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Can famotidine and omeprazole be combined on a once-daily basis?

OBJECTIVE

Prompt and long-standing acid control following once-daily administration of antisecretory drugs is desirable. The objective of this study was to determine whether co-administration of a well-characterized H2-receptor antagonist, famotidine, can be combined with the proton-pump inhibitor omeprazole.

MATERIAL AND METHODS

Intragastric 24-h pH-metry was performed in healthy, Helicobacter pylori-negative volunteers on day 1 and after 8 days of daily administration of 20 mg omeprazole, 10 mg famotidine, or a combination of these in a three-way crossover design.

RESULTS

A combination of famotidine and omeprazole raised the gastric pH level to >4 in less than 1 h. The percentage of daytime with pH > 4 on day 1 was significantly higher with the combination of omeprazole and famotidine (median: 37%) than that with omeprazole alone (22%; p < 0.05). On day 8, daytime intragastric pH > 4 following treatment with omeprazole (median: 55%) or a combination of omeprazole and famotidine (61%) was superior (p < 0.05) to that with famotidine (21%). On day 1 treatment with both famotidine and the combination (famotidine and omeprazole) showed a significantly shorter time to reach a pH of 4 (medians: 93 and 63 min, respectively) compared with treatment with omeprazole alone (173 min; p < 0.05).

CONCLUSIONS

Compared with treatment with omeprazole alone, on day 1 famotidine and omeprazole in combination improved the duration of and time to reach intragastric pH > 4. With regard to duration with pH > 4, the combination therapy was superior to famotidine alone on day 8. The rapid acid control with an H2-receptor antagonist may be combined with the long-lasting antisecretory effect of a proton-pump inhibitor.