Immunolab: Combining targeted real-world data with advanced analytics to generate evidence at scale in immunology

Real-world evidence (RWE) has traditionally been used by regulatory or payer authorities to inform disease burden, background risk, or conduct post-launch pharmacovigilance, but in recent years RWE has been increasingly used to inform regulatory decision-making. However, RWE data sources remain fragmented, and datasets are disparate and often collected inconsistently. To this end, we have constructed an RWE-generation platform, Immunolab, to facilitate data-driven insights, hypothesis generation and research in immunological diseases driven by type 2 inflammation. Immunolab leverages a large, anonymized patient cohort from the Optum electronic health record and claims dataset containing over 17 million patient lives. Immunolab is an interactive platform that hosts three analytical modules: the Patient Journey Mapper, to describe the drug treatment patterns over time in patient cohorts; the Switch Modeler, to model treatment switching patterns and identify its drivers; and the Head-to-Head Simulator, to model the comparative effectiveness of treatments based on relevant clinical outcomes. The Immunolab modules utilize various analytic methodologies including machine learning algorithms for result generation which can then be presented in various formats for further analysis and interpretation.

Concordance between physiotherapists and physicians for care of patients with musculoskeletal disorders presenting to the emergency department

Background

Overcrowding in emergency departments (ED) is a major concern worldwide. To answer increasing health care demands, new models of care including advanced practice physiotherapists (APP) have been implemented in EDs. The purpose of this study was to assess diagnostic, treatment and discharge plan concordance between APPs and ED physicians for patients consulting to the ED for minor musculoskeletal disorders (MSKD).

Methods

Patients presenting to two EDs in Montréal (Canada) with a minor MSKD were recruited and independently assessed by an APP and ED physician. Both providers had to formulate diagnosis, treatment and discharge plans. Cohen’s kappa (κ) and Prevalence and Bias Adjusted Kappas (PABAK) with associated 95%CI were calculated. Chi Square and t-tests were used to compare treatment, discharge plan modalities and patient satisfaction between providers.

Results

One hundred and thirteen participants were recruited, mean age was 50.3 ± 17.4 years old and 51.3% had an atraumatic MSKD. Diagnostic inter-rater agreement between providers was very good (κ = 0.81; 95% CI: 0.72–0.90). In terms of treatment plan, APPs referred significantly more participants to physiotherapy care than ED physicians (κ = 0.27; PABAK = 0.27; 95% CI: 0.07–0.45; p = 0.003). There was a moderate inter-rater agreement (κ = 0.46; PABAK = 0.64; 95% CI: 0.46–0.77) for discharge plans. High patient satisfaction was reported with no significant differences between providers (p = 0.57).

Conclusion

There was significant agreement between APPs and ED physicians in terms of diagnosis and discharge plans, but more discrepancies regarding treatment plans. These results tend to support the integration of APPs in ED settings, but further prospective evaluation of the efficiency of these types of models is warranted.

Comparison of text processing methods in social media-based signal detection

PURPOSE

Adverse event (AE) identification in social media (SM) can be performed using various types of natural language processing (NLP) and machine learning (ML). These methods can be categorized by complexity and precision level. Co-occurrence-based ML methods are rather basic, as they identify simultaneous appearance of drugs and clinical events in a single post. In contrast, statistical learning methods involve more complex NLP and identify drugs, events, and associations between them. We aimed to compare the ability of co-occurrence and NLP to identify AEs and signals of disproportionate reporting (SDR) in patient-generated SM. We also examined the performance of lift in SM-based signal detection (SD).

METHODS

Our examination was performed in a corpus of SM posts crawled from open online patient forums and communities, using the spontaneously reported VigiBase data as reference data set.

RESULTS

We found that co-occurrence and NLP produce AEs, which are 57% and 93% consistent with VigiBase AEs, respectively. Among the SDRs identified both in SM and in VigiBase, up to 55.3% were identified earlier in co-occurrence, and up to 32.1% were identified earlier in NLP-processed SM. Using lift in SM SD provided performance similar to frequentist methods, both in co-occurrence and in NLP-processed AEs.

CONCLUSION

Our results indicate that using SM as a data source complementary to traditional pharmacovigilance sources should be considered further. Various levels of SM processing may be considered, depending on the preferred policies and tolerance for false-positive to false-negative balance in routine pharmacovigilance processes.

In vitro interactions between apricitabine and other deoxycytidine analogues

Apricitabine is a novel deoxycytidine analogue reverse transcriptase inhibitor that is under development for the treatment of human immunodeficiency virus type 1 (HIV-1) infection. Apricitabine is phosphorylated to its active triphosphate by deoxycytidine kinase, which is also responsible for the intracellular phosphorylation of lamivudine (3TC) and emtricitabine (FTC); hence, in vitro studies were performed to investigate possible interactions between apricitabine and these agents. Human peripheral blood mononuclear cells (PBMC) were incubated for 24 h with various concentrations of (3)H-labeled or unlabeled apricitabine, 3TC, or FTC. Intracellular concentrations of parent compounds and their phosphorylated derivatives were measured by high-performance liquid chromatography. In other experiments, viral reverse transcriptase activity was measured in PBMC infected with HIV-1 bearing M184V in the presence of various concentrations of apricitabine and 3TC. [(3)H]apricitabine and [(3)H]3TC were metabolized intracellularly to form mono-, di-, and triphosphates. 3TC and FTC (1 to 10 microM) produced concentration-dependent decreases in apricitabine phosphorylation; in contrast, apricitabine at concentrations of up to 30 muM had no effect on the phosphorylation of 3TC or FTC. The combination of apricitabine and 3TC reduced the antiviral activity of apricitabine against HIV-1: apricitabine concentrations producing 50% inhibition of viral reverse transcriptase were increased two- to fivefold in the presence of 3TC. These findings suggest that nucleoside reverse transcriptase inhibitors with similar modes of action may show biochemical interactions that affect their antiviral efficacy. It is therefore essential that potential interactions between combinations of new and existing agents be thoroughly investigated before such combinations are introduced into clinical practice.

Atmospheric lead fallout over the last century recorded in Gulf of Lions sediments (Mediterranean Sea)

Six marine sediment cores from the Gulf of Lions continental slope (700-1700 m water depth) were analyzed for stable lead isotopes and (210)Pb geochronology in order to reconstruct lead atmospheric fallout pattern during the last century. The detrital lead contribution is 25 microg g(-1) and the mean sediment anthropogenic inventory is 110+/-7 microg cm(-2), a little bit higher than atmospheric deposition estimate. Anthropogenic lead accumulation in sediments peaked in early 1970s (1973+/-2) in agreement with lead emissions features. For the period 1986-1997, the sediment signal also reflect the decrease of atmospheric lead described by independent atmospheric fallout investigations. The anthropogenic Pb deposition in the late 1990s was similar to the 1950s deposition, attesting thus of the output of European environmental policies.

A multicenter, randomized, double-blind, 8-week comparative trial of low-dose esomeprazole (20 mg) and standard-dose omeprazole (20 mg) in patients with erosive esophagitis

The objective of this trial was to compare the efficacy of esomeprazole, 20 mg, with that of omeprazole, 20 mg, in patients with erosive esophagitis (EE). In this multicenter, double-blind, parallel-group trial, 1176 patients with EE confirmed by endoscopy (Helicobacter pylori-negative by serology) were randomized to once-daily treatment with 20 mg esomeprazole or 20 mg omeprazole for 8 weeks. The primary outcome was the proportion of patients with healed EE through week 8. Secondary outcomes included diary and investigator assessments of heartburn symptoms. Cumulative life-table healing rates at week 8 were similarly high for 20 mg esomeprazole (90.6%; 95% confidence interval, 88.1%-93%) and 20 mg omeprazole (88.3%; 95% confidence interval, 85.5%-91.0%). The two treatments were comparable for other secondary measures and had similar tolerability profiles.

A multicenter, randomized, double-blind, 8-week comparative trial of standard doses of esomeprazole (40 mg) and omeprazole (20 mg) for the treatment of erosive esophagitis

To compare esomeprazole with omeprazole for healing erosive esophagitis (EE), 1148 patients with endoscopically confirmed EE were randomized to once-daily esomeprazole, 40 mg, or omeprazole, 20 mg, for 8 weeks in this multicenter, double-blind, parallel-group trial. The primary outcome was the proportion of patients with healed EE at week 8. Secondary outcomes included diary and investigator assessments of heartburn symptoms. At week 8, estimated healing rates were 92.2% (95% CI, 89.9%-94.5%) with esomeprazole and 89.8% (95% CI, 87.2%-92.4%) with omeprazole. Healing rates with esomeprazole were significantly higher than those with omeprazole at weeks 8 (88.4% vs 77.5%; P = 0.007) and 4 (60.8% vs 47.9%; P = 0.02) in patients with moderate to severe (Los Angeles grade C or D) EE at baseline but were not significantly different for patients with mild (Los Angeles grade A or B) EE. Both treatments were comparable for other secondary measures and had similar tolerability profiles.

The respective roles of controlled clinical trials and cohort monitoring studies in the pre- and postmarketing assessment of drugs

The respective roles of controlled clinical trials and observational studies (cohort or case-control studies) in evaluating the efficacy, safety and usefulness of a drug were analysed. A randomised, controlled, double-blind study is the best method of estimating the efficacy of a treatment. It provides the least biased and most robust estimate of the causal relationship. In certain situations and on the basis of certain criteria, observational studies can have a proof-of-efficacy value. Randomised, controlled, pre- and postmarketing authorisation (MA) clinical studies identify the rarer adverse effects and compare them with those resulting from the reference treatment. Before the MA, the pooled safety data from different controlled trials can provide an estimation of relatively frequent adverse events and subjects at risk. However, an observational study is the most appropriate method of evaluating the safety of a drug in the currently used conditions. By definition, a drug influences the health of a population if it directly or indirectly improves its health. A drug would have a major role in public health if it reduced mortality or morbidity related to a particular disease or if it improved the quality of life of patients with this disease. Prior to marketing a product, modelling is the approach of choice to quantify the expected effect. Pragmatic, postmarketing trials and observational studies are the reference methods used to define the population affected, the efficacy and safety of the drug in a real situation and its usefulness for public health. In conclusion, randomised clinical trials remain the reference approach for evaluating efficacy, while observational studies have a confirmatory value. Observational studies are the most appropriate way of evaluating safety in the currently used conditions, as the clinical trial has limited indications. In the interests of public health, modelling is the pre-marketing approach of choice, while pragmatic trials and observational studies are the postmarketing reference approaches.

Extra-intestinal manifestations associated with irritable bowel syndrome: a twin study

BACKGROUND

Little is known about the role of genetic and environmental factors in irritable bowel syndrome. Various extra-intestinal manifestations are more prevalent in cases than in controls. Genetic effects may be important in the liability to develop functional bowel disorders.

AIMS

To evaluate the associations of irritable bowel syndrome with several disorders co-morbid with the condition, using both a case-control design and a co-twin control design.

METHODS

A sample of 850 Swedish twin pairs, aged 18-85 years, was contacted for a telephone interview. Through a diagnostic algorithm, 72 unrelated cases of irritable bowel syndrome and 216 age- and gender-matched controls were identified. Fifty-eight twin pairs discordant for irritable bowel syndrome were evaluated in co-twin analyses.

RESULTS

Renal problems (odds ratio (OR)=3.3; confidence interval (CI), 1.3-8.2), obesity (OR=2.6; CI, 1.0-6.4), underweight in the past (OR=2.4; CI, 1.1-6.4), gluten intolerance (OR=9.0; CI, 1.4-60.1), rheumatoid arthritis (OR=3.2; CI, 1.1-9.4) and poor self-rated health (OR=1.8; CI, 1.0-3.2) were significantly associated with irritable bowel syndrome. In the co-twin analyses, the only factors maintaining significance were renal and recurrent urinary tract problems.

CONCLUSIONS

The association between irritable bowel syndrome and renal and urinary tract problems does not reflect a genetic or familial mediation. Eating disorders in childhood represent a familial-environmental influence on irritable bowel syndrome, whereas the association with rheumatoid arthritis and perhaps gluten intolerance probably reflects genetic mediation.

Three-dimensional imaging of crystal defects by `topo-tomography'

A new technique, `topo-tomography', suitable for the characterization of the three-dimensional defect structure in bulk crystals, is proposed. The technique consists of the combination of diffraction topography and microtomography. It is applicable to high-quality single crystals, provided that the `direct image' is the dominant contrast mechanism. In this case, crystal defects give rise to locally enhanced intensity compared with the perfect-crystal matrix. The additional intensities sum along the diffracted-beam direction and yield projections of the local Bragg reflectivity. Like in the case of absorption tomography, the three-dimensional distribution of this reflectivity can be reconstructed from a large number of projections. The first experimental results of this technique, applied to a synthetic diamond crystal, are presented.

The new proton pump inhibitor esomeprazole is effective as a maintenance therapy in GERD patients with healed erosive oesophagitis: a 6-month, randomized, double-blind, placebo-controlled study of efficacy and safety

BACKGROUND

Esomeprazole, the S-isomer of omeprazole, is the first proton pump inhibitor to be developed as an optical isomer. In patients with erosive oesophagitis, esomeprazole has produced significantly greater healing rates and improved symptom resolution vs. omeprazole.

AIM

This study assesses the efficacy of esomeprazole for preventing relapse in patients with healed oesophagitis.

METHODS

In this 6-month US multicentre randomized double-blind placebo-controlled trial, 375 Helicobacter pylori-negative patients with endoscopically healed oesophagitis received esomeprazole 40 mg, 20 mg, 10 mg, or placebo once daily. The primary efficacy end-point was maintenance of healing at 6 months. Secondary end-points assessed changes in symptoms, and long-term safety and tolerability.

RESULTS

Significantly (P < 0.001) more patients remained healed with esomeprazole 40 mg (87.9%), 20 mg (78.7%), or 10 mg (54.2%), than with placebo (29.1%). Relapse, when it occurred, was later with esomeprazole. Sustained resolution of heartburn was observed in the 40 mg and 20 mg groups; there was a high correlation between absence of heartburn and maintenance of healing. Adverse effects were mild, infrequent and not significantly different between groups.

CONCLUSIONS

Esomeprazole is effective and well-tolerated in the maintenance of healing of erosive oesophagitis. Esomeprazole 40 mg and 20 mg offer significant clinical benefit to patients.

Efficacy and safety of esomeprazole compared with omeprazole in GERD patients with erosive esophagitis: a randomized controlled trial

OBJECTIVE

In patients with gastroesophageal reflux disease (GERD), esomeprazole, the S-isomer of omeprazole, has demonstrated pharmacological and clinical benefits beyond those seen with the racemic parent compound. This study was designed to further evaluate the efficacy and tolerability of esomeprazole relative to that of omeprazole in healing erosive esophagitis and resolving accompanying symptoms of GERD.

METHODS

Esomeprazole 40 mg was compared with omeprazole 20 mg once daily in 2425 patients with erosive esophagitis (Helicobacter pylori negative by serology) in an 8-wk, multicenter, randomized, double-blind, parallel-group study conducted in 163 centers throughout the US. The primary efficacy endpoint was the proportion of patients with healed esophagitis at wk 8. Secondary endpoints were the proportion of patients healed at wk 4, resolution of heartburn at wk 4, time to first resolution and sustained resolution of heartburn, and proportion of heartburn-free days and nights. Safety and tolerability were also assessed.

RESULTS

Significantly more patients were healed with esomeprazole versus omeprazole at wk 8 (93.7% vs 84.2%, p < 0.001; life table estimates, intention-to-treat analysis). Healing rates at wk 4 were 81.7% and 68.7%, respectively. Esomeprazole was superior to omeprazole for all secondary measures and had a similar safety profile. The most common adverse events in both treatment groups were headache, diarrhea, and nausea.

CONCLUSIONS

Esomeprazole demonstrates significantly greater efficacy than omeprazole in the treatment of GERD patients with erosive esophagitis. The tolerability and safety of esomeprazole are comparable to that of omeprazole. (Am

Efficacy and safety of esomeprazole compared with omeprazole in GERD patients with erosive esophagitis: a randomized controlled trial

OBJECTIVE

In patients with gastroesophageal reflux disease (GERD), esomeprazole, the S-isomer of omeprazole, has demonstrated pharmacological and clinical benefits beyond those seen with the racemic parent compound. This study was designed to further evaluate the efficacy and tolerability of esomeprazole relative to that of omeprazole in healing erosive esophagitis and resolving accompanying symptoms of GERD.

METHODS

Esomeprazole 40 mg was compared with omeprazole 20 mg once daily in 2425 patients with erosive esophagitis (Helicobacter pylori negative by serology) in an 8-wk, multicenter, randomized, double-blind, parallel-group study conducted in 163 centers throughout the US. The primary efficacy endpoint was the proportion of patients with healed esophagitis at wk 8. Secondary endpoints were the proportion of patients healed at wk 4, resolution of heartburn at wk 4, time to first resolution and sustained resolution of heartburn, and proportion of heartburn-free days and nights. Safety and tolerability were also assessed.

RESULTS

Significantly more patients were healed with esomeprazole versus omeprazole at wk 8 (93.7% vs 84.2%, p < 0.001; life table estimates, intention-to-treat analysis). Healing rates at wk 4 were 81.7% and 68.7%, respectively. Esomeprazole was superior to omeprazole for all secondary measures and had a similar safety profile. The most common adverse events in both treatment groups were headache, diarrhea, and nausea.

CONCLUSIONS

Esomeprazole demonstrates significantly greater efficacy than omeprazole in the treatment of GERD patients with erosive esophagitis. The tolerability and safety of esomeprazole are comparable to that of omeprazole. (Am

Esomeprazole once daily for 6 months is effective therapy for maintaining healed erosive esophagitis and for controlling gastroesophageal reflux disease symptoms: a randomized, double-blind, placebo-controlled study of efficacy and safety

OBJECTIVE

Esomeprazole, the S-isomer of omeprazole, achieves a significantly greater healing rate and symptom resolution of erosive esophagitis than that achieved by omeprazole. The objective of this study is to assess the efficacy of the new proton pump inhibitor esomeprazole in preventing relapse over a prolonged period in patients with healed erosive esophagitis.

METHODS

A total of 318 gastroesophageal reflux patients whose erosive esophagitis was healed in a comparative study of esomeprazole 40 mg, 20 mg, or omeprazole 20 mg, were randomized to maintenance therapy with once daily esomeprazole 40 mg, 20 mg, or 10 mg, or placebo in a U.S., double-blind multicenter trial.

RESULTS

After 6 months, healing was maintained (cumulative life table rates) in 93.6% (95% CI 87.4-99.7) of patients treated with esomeprazole 40 mg, 93.2% (95% CI 87.4-99.0) treated with esomeprazole 20 mg, and 57.1% (95% CI 45.2-69) treated with esomeprazole 10 mg; p < 0.001 vs placebo (29.1%; 95% CI 17.7-40.3). Of patients relapsing, mean time to first recurrence of esophagitis increased with dose, from 34 days (placebo) to 78 days (10 mg), 115 days (20 mg), and 163 days (40 mg). Patients treated with esomeprazole had less frequent and less severe heartburn than those treated with placebo. At month 6, more than 70% of patients being treated with esomeprazole remained symptom-free.

CONCLUSIONS

Esomeprazole is effective and well tolerated in the maintenance of a healing erosive esophagitis. Esomeprazole 40 mg and 20 mg maintain healing in over 90% of patients while providing effective control of heartburn symptoms.

Esomeprazole improves healing and symptom resolution as compared with omeprazole in reflux oesophagitis patients: a randomized controlled trial. The Esomeprazole Study Investigators

BACKGROUND

The pharmacologic profile of the new proton pump inhibitor esomeprazole has demonstrated advantages over omeprazole that suggest clinical benefits for patients with acid-related disease.

METHODS

1960 patients with endoscopy-confirmed reflux oesophagitis (RO) were randomized to once daily esomeprazole 40 mg (n=654) or 20 mg (n=656), or omeprazole 20 mg (n=650), the standard recommended dose for RO, for up to 8 weeks in a US, multicentre, double-blind trial. The primary efficacy variable was the proportion of patients healed at week 8. Secondary variables included healing and heartburn resolution at week 4, time to first resolution and sustained resolution of heartburn, and per cent of heartburn-free days and nights. Safety and tolerability were also evaluated.

RESULTS

Significantly more patients were healed at week 8 with esomeprazole 40 mg (94.1%) and 20 mg (89.9%) vs. omeprazole 20 mg (86.9%), using cumulative life table estimates, ITT analysis (each P < 0.05). Esomeprazole 40 mg was also significantly more effective than omeprazole for healing at week 4 and for all secondary variables evaluating heartburn resolution. The most common adverse events in all treatment groups were headache, abdominal pain and diarrhoea.

CONCLUSION

Esomeprazole was more effective than omeprazole in healing and symptom resolution in GERD patients with reflux oesophagitis, and had a tolerability profile comparable to that of omeprazole.

Pharmacokinetic and pharmacodynamic interaction between mexiletine and propafenone in human beings

BACKGROUND AND OBJECTIVE

Mexiletine and propafenone are often used concomitantly and are metabolized by the same cytochrome P450 isozymes, namely CYP2D6, CYP1A2, and probably CYP3A4. Our objective was to study the potential pharmacokinetic and electrophysiological interactions between mexiletine and propafenone.

METHODS

Fifteen healthy volunteers, 8 extensive metabolizers and 7 poor metabolizers of CYP2D6, received oral doses of mexiletine 100 mg two times daily from day 1 to day 8 and oral doses of propafenone 150 mg two times daily from day 5 to day 12. Interdose studies were performed at steady-state on mexiletine alone (day 4), mexiletine plus propafenone (day 8), and propafenone alone (day 12).

RESULTS

In subjects in the extensive metabolizer group, coadministration of propafenone decreased oral clearances of R-(-)-mexiletine (from 41+/-11 L/h to 28+/-7 L/h) and S-(+)-mexiletine (from 43+/-15 L/h to 29+/-11 L/h) to an extent such that these values were no longer different between the extensive and the poor metabolizer groups. Propafenone coadministration also decreased partial metabolic clearances of mexiletine to hydroxymethylmexiletine, p-hydroxymexiletine, and m-hydroxymexiletine in extensive metabolizers by 71%, 67%, and 73%, respectively. In contrast, propafenone did not alter the kinetics of mexiletine enantiomers in subjects in the poor metabolizer group except for a slight decrease in the formation of hydroxymethylmexiletine. Pharmacokinetic parameters of propafenone were not changed during concomitant administration of mexiletine in subjects of either phenotype. Finally, electrocardiographic parameters (QRS duration, QTc, RR, and PR intervals) were not modified during the combined administration of the drugs.

CONCLUSION

Propafenone is a potent CYP2D6 inhibitor that may cause an increase in plasma concentrations of coadministered CYP2D6 substrates.

The effect of mosapride, a novel prokinetic, on acid reflux variables in patients with gastro-oesophageal reflux disease

BACKGROUND

Mosapride is a novel prokinetic agent facilitating acetylcholine release from the enteric cholinergic neurones through a selective 5-HT4 receptor agonistic action. It is also active through its main metabolite M1, which is a 5-HT3 antagonist. The importance of motor dysfunction in the pathogenesis of gastro-oesophageal reflux disease (GERD) makes it interesting to examine the effect of mosapride on oesophageal acid exposure.

METHODS

The effect of mosapride on oesophageal 24-h acid reflux variables was studied in 21 patients with GERD symptoms and a pre-entry total acid exposure time (pH < 4) of more than 5%. Ambulatory pH monitoring was performed after treatment with 40 mg mosapride citrate or placebo q.d.s. for 2 days in random order, using a double-blind crossover technique, with a washout period of at least 5 days.

RESULTS

Mosapride was significantly more effective than placebo in decreasing the total number of reflux episodes, the total number of reflux episodes lasting more than 5 min and the total time, as well as the amount of day time, of intra-oesophageal pH below 4. Consequently, mosapride also significantly improved total acid clearance time.

CONCLUSION

Mosapride 40 mg q.d.s. is effective in decreasing acid reflux in the oesophagus in patients with GERD and therefore has the potential to be effective in the treatment of this disease.

Twenty-four-hour intragastric acidity and plasma gastrin during 3-month treatment with omeprazole in healthy subjects

BACKGROUND

Prolonged treatment with omeprazole 20 or 40 mg/day is sometimes required, especially for severe oesophagitis. However, information about long-term effects on intragastric acidity and plasma gastrin response with such drug regimens is scarce.

METHODS

Sixteen healthy subjects (11 men, 5 women, mean age 29 years) randomly received either 20 or 40 mg of omeprazole once daily (at 08.00 h) for 3 months. Gastric pH was recorded every 6 s for 24 h from noon to noon under standardized conditions, and blood samples were collected hourly in order to determine the 24-h plasma gastrin response on day 0 (pre-entry), day 7, day 28 and day 90.

RESULTS

From day 0 to day 7, 24-h median pH increased from 1.7 to 4.6 and mean percentage of time at pH < 4 decreased from 89% to 35% with omeprazole 20 mg. Respective values with omeprazole 40 mg were 1.9 to 4.3, and 89% to 34%. Inhibition of gastric acidity remained unchanged during the 3 months of treatment. Despite similar effects on the basis of 24-h analysis, the decrease in daytime acidity was slightly higher with omeprazole 40 mg than with omeprazole 20 mg. Twenty-four-hour integrated plasma gastrin significantly increased with both drug regimens between day 0 and day 7 (P < 0.01), and between day 7 and day 28 (P < 0.01) with omeprazole 40 mg; there was no significant increase between day 28 and day 90 with either of the drug regimens.

CONCLUSION

Omeprazole 20 and 40 mg/day provides long-term stable acid suppression with a progressive increase in gastrin response, stabilizing after 2 months of treatment.

Treating the symptoms of gastro-oesophageal reflux disease: a double-blind comparison of omeprazole and cisapride

BACKGROUND

Few studies have specifically addressed the management of the symptoms of gastro-oesophageal reflux disease, and there are no comparative data in this respect for acid pump inhibitors and prokinetic agents.

METHODS

Following endoscopy 424 patients presenting with heartburn as the predominant symptom of gastro-oesophageal reflux disease were randomized to treatment with omeprazole 20 or 10 mg once daily, or cisapride 10 mg four times daily, in a double-blind, double-dummy, parallel group, multicentre study. Symptoms and quality of life were assessed at 4 weeks. Patients still experiencing heartburn continued therapy for a further 4 weeks and the assessments were repeated.

RESULTS

At 4 weeks, heartburn was resolved in 65% (95% CI: 57-73%), 56% (48-64%) and 41% (32%-49%) of patients treated, respectively, with omeprazole 20 mg and 10 mg once daily, and cisapride. Both omeprazole doses were significantly more effective than cisapride (P < 0.01). The same order of efficacy was observed regardless of the presence of erosive oesophagitis. Regurgitation and epigastric pain also improved to a greater degree with omeprazole than with cisapride. Quality of life was improved in all treatment groups, and the improvement in the reflux dimension of the Gastrointestinal Symptom Rating Scale (GSRS) score was significantly different between groups (P = 0.002).

CONCLUSIONS

Omeprazole 20 or 10 mg once daily is significantly more effective than cisapride in the resolution of heartburn, regardless of the presence of erosive oesophagitis, and this is accompanied by an improvement in patient quality of life.

[Comparison of the cost-efficacy ratio of omeprazole and ranitidine in the treatment of reflux esophagitis]

OBJECTIVE

The objective of this study was to compare the cost of achieving a unit of clinical success for treatment of reflux oesophagitis with either ranitidine or omeprazole.

METHODS

After randomisation 430 patients with reflux oesophagitis (grade 2 or 3) were assigned to receive omeprazole 20 mg or ranitidine 150 b.i.d. for 8 weeks. Patients were given diary cards to assess their symptoms every day, and record every two weeks a life satisfaction index. Patients were seen after 4 and 8 weeks for symptoms assessment and repeat endoscopy at 8 weeks. The perspective of the analysis was that of the payer. The costs of medical care were based in French drug costs currently advertised, payment for physician and actual mean payment for upper GI endoscopy.

RESULTS

The healing rates at 8 weeks in the omeprazole group and the ranitidine group were 93 and 67.5% respectively. After 8 weeks of treatment, life satisfaction was good in 81 and 53.6% and the relief of pain was 86,6 and 69,5% respectively. For each effectiveness criteria, omeprazole was more cost effective than ranitidine: cost per healed patient (2,338 F vs 2,744 F), cost per asymptomatic patient (2,510 F vs 2,964 F), cost per patient with a good or very good life satisfaction index (2,687 F vs 3,456 F). This advantage remained independent of the oesophagitis initial severity. The sensitivity analysis showed that the results were unsensitive to the variations of the efficacy variables in their confidence interval.

CONCLUSIONS

This cost-effectiveness analysis suggests that in the treatment of reflux oesophagitis, the strategy with the more effective treatment is more cost-effective.

[Prognostic factors of the speed of cicatrization in duodenal ulcer. Controlled trial of omeprazole versus ranitidine]

OBJECTIVES

The treatment of duodenal ulcers has changed greatly since the introduction of anti-H2 drugs and sodium pump inhibitors. However the effect of several factors influencing prognosis and the rate of healing remain to be elucidated.

METHODS

Five hundred forty five patients with a fibroscopically proven duodenal ulcer were included in a randomized controlled trial and were treated for one month with omeprazole (20 mg) or ranitidine (300 mg). Twenty epidemiological, clinical and fibroscopic factors of prognosis were recorded when the patients entered in the study and were analyzed after the treatment period.

RESULTS

Endoscopic healing was obtained in 90% of the omeprazole treated patients and in 78% of the ranitidine group (p < 0.001). Multifactorial analysis of the 20 prognostic factors showed that, excepting the treatment factor, only the size of the ulcer (less than 11 mm), its shape (round), its localisation (not on the posterior side) and a moderate pain were factors of good prognosis. Paradoxically, in our study, male patients and alcohol consumption were also positive factors of prognosis.

CONCLUSION

The probability of healing is best for round, small duodenal ulcers located on the anterior side of the bulb.

[Prognostic factors influencing healing of reflux esophagitis. A controlled trial of omeprazole versus ranitidine. Study group Omega]

Four hundred and thirty patients with grade 2 or 3 esophagitis were treated after 2/1 randomization for 8 weeks with omeprazole 20 mg (n = 294) or ranitidine 150 mg bid (n = 136). Apart from treatment, 8 epidemiological factors (gender, age, occupation, obesity, smoking, alcohol, NSAID, and coffee or tea consumption), 5 clinical factors (day/night pain distribution, burning score, severity of regurgitation and of dysphagia, number of painful episodes requiring prescription of an antisecretory agent during the previous year, and onset of symptoms before age 30) and 3 endoscopic factors (grade and upward extension of esophagitis, and existence of hiatal hernia > or = 5 cm) were analysed. The influence of these factors on healing at 8 weeks and on changes in symptoms was evaluated by multivariate analysis. 92.1% of patients enrolled were analyzed. In comparison with ranitidine, omeprazole increased the percentage of healed patients (93% v. 67.5%, p < 0.001) and the rapidity of disappearance of symptoms (5 days v. 7 days, p < 0.001). Independent good prognostic factors associated with healing rate were treatment with omeprazole (p < 0.001) and grade 2 esophagitis (p < 0.001) while those associated with the disappearance of symptoms were a low burning score (p = 0.001), advanced age (p = 0.004), treatment with omeprazole (p = 0.005), the absence of any occupation (p = 0.01) and male gender (p = 0.017). The results of this study show that, apart from treatment, endoscopic factors are predictive of the healing of reflux esophagitis treated by antisecretory agents while clinical factors are more important with regard to the disappearance of symptoms.

Detection by DGGE of a new polymorphism closely linked to the adenomatous polyposis coli region

The EF5.44 locus is in close proximity to the chromosome 5 region to which the genetic defect responsible for familial adenomatous polyposis has been mapped. We have devised two oligonucleotides that promote the specific polymerase chain reaction (PCR) amplification of a 365-bp sequence in this region. Analysis by denaturing gradient gel electrophoresis of the resulting fragment has unravelled individual differences that could be identified as a single base pair change in a MnlI restriction site. This PCR assayable polymorphism increases the informativeness at this locus, and should be useful in the presymptomatic diagnosis of familial adenomatous polyposis.

Independent risk factors for hepatocellular carcinoma in French drinkers

The aim of this study was to assess whether markers of hepatitis B virus or hepatitis C virus infection are independent risk factors for hepatocellular carcinoma in drinkers after adjustment for three known risk factors: cirrhosis, age and male sex. Among 2,015 consecutive drinkers admitted, hepatitis C virus antibodies were found by sensitive radioimmunoassay in 1,259. The following five factors have been identified and ranked as risk factors for hepatocellular carcinoma in unidimensional and regression analysis: cirrhosis (p less than 0.001), age (p less than 0.001), male sex (p less than 0.001), presence of HBsAg (p less than 0.001) and presence of hepatitis C virus antibodies (p less than 0.03). Among drinkers with cirrhosis, the patients with hepatocellular carcinoma were older (64 +/- 11 yr vs. 56 +/- 9 yr; p less than 0.001), were more often male (93% vs. 65%; p less than 0.0001) and had higher prevalence of HBsAg (9% vs. 2%; p = 0.02) and hepatitis C virus antibodies (41% vs. 26%; p = 0.02). A simple algorithm permitted us to identify a high-risk population of drinkers: the male cirrhotic patient older than 50 yr. The relative risk of hepatocellular carcinoma in this selected population was 17.7 (95% confidence interval = 9.0 to 37.5; p less than 0.0001). From a pragmatic point of view, the detection of HBsAg or hepatitis C virus antibodies, although independently associated with hepatocellular carcinoma, is not useful in increasing the diagnostic value of this algorithm because of the poor sensitivity of these tests. The weak relationships observed between hepatitis C virus antibodies and hepatocellular carcinoma needs confirmation by more accurate tests.

Association between HCV and HBV infection in hepatocellular carcinoma and alcoholic liver disease

We conducted a retrospective study in 229 patients to determine the prevalence of hepatitis C virus (HCV) according to the type of liver disease and also the serum hepatitis B virus (HBV) status. There were 55 cases of hepatocellular carcinoma (HCC), 78 cases of alcoholic cirrhosis (AC) and 96 cases of non-cirrhotic alcohol liver disease (NCA). Half the AC and NCA groups were constituted of patients with or without serum HBV markers. The prevalence of anti-HCV antibodies in HCC (58.2%) was significantly higher than in the other groups (AC, 35.9%; NCA, 17.7%). Combining the two AC and NCA groups gave a 25.8% anti-HCV prevalence in the alcoholics. Altogether anti-HCV antibodies were more frequently present in HBV-positive than in HBV-negative patients (42.2 vs. 26.1%, p less than 0.01), although the difference was not significant when the HCC group was separately analysed. The S/N ratio of anti-HCV-positive samples varied according to the type of the disease (tumorous vs. non-tumorous) and to the serum HBV status. Indeed, 65.6% of HCC had a S/N greater than 4 compared to only 32.2 and 23.5% in AC and NCA, respectively (p less than 0.01). On the other hand more than half of the AC and NCA had a S/N less than 2, indicating possible artefacts in certain cases. The 15 HBsAg and anti-HCV-positive patients had a significantly lower mean S/N than patients displaying only antibodies against HBV, even in the HCC group.(ABSTRACT TRUNCATED AT 250 WORDS)

Priming of calcium mobilization in human neutrophils by granulocyte-macrophage colony-stimulating factor: evidence for an involvement of phospholipase D-derived phosphatidic acid

Human neutrophils pre-incubated with granulocyte-macrophage-colony-stimulating factor (GM-CSF) exhibit an enhanced mobilization of calcium in response to secondary stimuli such as chemotactic factors. The mechanisms underlying this priming effect of GM-CSF were examined. It was first demonstrated that the additional calcium mobilized by chemotactic factors in GM-CSF-treated cells was derived from intracellular stores and was associated neither with an increased permeability to calcium nor with production of inositol 1,4,5-trisphosphate. These results indicated that GM-CSF called upon a novel mechanism in order to enhance the mobilization of calcium in human neutrophils. The growth factor has recently been shown to prime phospholipase D leading to an enhanced activation by chemotactic factors and an augmented production of phosphatidic acid. Furthermore the ability of exogenous phosphatidic acid to mobilize calcium in cell types other than neutrophils has been previously demonstrated. Therefore, we examined the potential involvement of phospholipase D in the priming of the calcium response by GM-CSF in human neutrophils. Inhibition of the production of the fMet-Leu-Phe-stimulated production of phosphatidic acid by ethanol or wortmannin had only marginal effects on the concurrent mobilization of calcium. However, the priming of the mobilization of calcium by GM-CSF was greatly decreased in cells treated with either ethanol or wortmannin. These results provide strong support for the hypothesis that the production of phosphatidic acid, which is enhanced in GM-CSF-treated cells, is linked to an increased mobilization of intracellular calcium. These results may have relevance to the mechanism of action of GM-CSF in mature haematopoeitic cells as well to the mitogenic activity of other growth factors.

Differential expression of insulin-like growth factor II mRNA in human primary liver cancers, benign liver tumors, and liver cirrhosis

We investigated insulin-like growth factor II (IGF-II) mRNA in three groups of human liver samples including primary liver cancers, benign liver tumors and cirrhosis; indeed these pathological conditions would allow us to distinguish between different steps in liver carcinogenesis. A 40- to 100-fold increase in IGF-II mRNA was shown in 9/40 of the liver cancer samples as compared to normal adult liver. RNA blot analysis using both IGF-II cDNA and oligonucleotide probes showed the reexpression of two fetal (6 and 5 kilobases) IGF-II transcripts in primary liver cancers and in some cirrhotic adjacent tissues; these included all the samples with enhanced IGF-II expression. By contrast the adult (5.3 kilobases) IGF-II transcript was identified in most of the benign liver tumors and liver cirrhosis; in addition, in some of these samples, the 5-kilobase fetal transcript was also detected. The increase of IGF-II mRNA in some liver cancers is consistent with an autocrine mechanism conferring a selective growth advantage to tumorous liver cells. Furthermore, these results indicate a differential expression of IGF-II transcripts in nonmalignant hepatocyte proliferation (benign liver tumors and cirrhosis) as compared to liver cancer. Finally this study suggests that, in liver cirrhosis and in some benign liver tumors, premalignant proliferative states might be identified by the presence of IGF-II fetal transcripts.