Short-term efficacy and safety of new biological agents targeting the interleukin-23-T helper 17 pathway for moderate-to-severe plaque psoriasis: a systematic review and network meta-analysis

A new generation of biologics targeting the interleukin-23-T helper 17 pathway has been developed. This study aimed to assess the short-term effectiveness and safety of these new agents using a network meta-analysis. Twenty-seven randomized clinical trials (10 629 patients) were identified by a comprehensive systematic literature review (PROSPERO 2015: CRD42015025472). Quality of evidence was assessed following Cochrane-compliant rules and the Grading of Recommendations, Assessment, Development and Evaluations approach. Efficacy and safety outcomes at weeks 10-16 were compared using a random-effects network meta-analysis within a frequentist framework to estimate pooled odds ratios (ORs) of direct and indirect comparisons among the therapeutic options. There were six direct drug-to-drug comparisons in the network, with a high degree of consistency between the direct and indirect evidence. From the available evidence, infliximab 5 mg kg^-1 every 8 weeks [OR 118·89, 95% confidence interval (CI) 60·91-232·04] and secukinumab 300 mg every 4 weeks (OR 87·07, 95% CI 55·01-137·82) are shown to be among the most effective short-term treatments, but are ranked as the biologics most likely to produce any adverse event or an infectious adverse event, respectively. Ustekinumab 90 mg every 12 weeks, the third most efficacious treatment (OR 73·67, 95% CI 46·97-115·56), was the only agent that did not show increased risk of adverse events compared with placebo. Treatment recommendations should also consider long-term outcomes and costs.

Ca2+-Calmodulin regulates SNARE assembly and spontaneous neurotransmitter release via v-ATPase subunit V0a1

Ca²⁺–Calmodulin binding to neuronal v-ATPase V0 subunit a1 (V100) regulates SNARE complex assembly for a putative subset of synaptic vesicles that sustain spontaneous release in Drosophila.

Most chemical neurotransmission occurs through Ca²⁺-dependent evoked or spontaneous vesicle exocytosis. In both cases, Ca²⁺ sensing is thought to occur shortly before exocytosis. In this paper, we provide evidence that the Ca²⁺ dependence of spontaneous vesicle release may partly result from an earlier requirement of Ca²⁺ for the assembly of soluble N-ethylmaleimide–sensitive fusion attachment protein receptor (SNARE) complexes. We show that the neuronal vacuolar-type H⁺-adenosine triphosphatase V0 subunit a1 (V100) can regulate the formation of SNARE complexes in a Ca²⁺–Calmodulin (CaM)-dependent manner. Ca²⁺–CaM regulation of V100 is not required for vesicle acidification. Specific disruption of the Ca²⁺-dependent regulation of V100 by CaM led to a >90% loss of spontaneous release but only had a mild effect on evoked release at Drosophila melanogaster embryo neuromuscular junctions. Our data suggest that Ca²⁺–CaM regulation of V100 may control SNARE complex assembly for a subset of synaptic vesicles that sustain spontaneous release.

Long-term cost-effectiveness analysis of endovascular versus open repair for abdominal aortic aneurysm based on four randomized clinical trials

Background

A number of published economic evaluations of elective endovascular aneurysm repair (EVAR) versus open repair for abdominal aortic aneurysm (AAA) have come to differing conclusions about whether EVAR is cost-effective. This paper reviews the current evidence base and presents up-to-date cost-effectiveness analyses in the light of results of four randomized clinical trials: EVAR-1, DREAM, OVER and ACE.

Methods

Markov models were used to estimate lifetime costs from a UK perspective and quality-adjusted life-years (QALYs) based on the results of each of the four trials. The outcomes included in the model were: procedure costs, surveillance costs, reintervention costs, health-related quality of life, aneurysm-related mortality and other-cause mortality. Alternative scenarios about complications, reinterventions and deaths beyond the trial were explored.

Results

Models based on the results of the EVAR-1, DREAM or ACE trials did not find EVAR to be cost-effective at thresholds used in the UK (up to £30 000 per QALY). EVAR seemed cost-effective according to models based on the OVER trial. These results seemed robust to alternative model scenarios about events beyond the trial intervals.

Conclusion

These analyses did not find that EVAR is cost-effective compared with open repair in the long term in trials conducted in European centres. EVAR did appear to be cost-effective based on the OVER trial, conducted in the USA. Caution must be exercised when transferring the results of economic evaluations from one country to another.

Charcot-Marie-Tooth 2B mutations in rab7 cause dosage-dependent neurodegeneration due to partial loss of function

The small GTPase Rab7 is a key regulator of endosomal maturation in eukaryotic cells. Mutations in rab7 are thought to cause the dominant neuropathy Charcot-Marie-Tooth 2B (CMT2B) by a gain-of-function mechanism. Here we show that loss of rab7, but not overexpression of rab7 CMT2B mutants, causes adult-onset neurodegeneration in a Drosophila model. All CMT2B mutant proteins retain 10–50% function based on quantitative imaging, electrophysiology, and rescue experiments in sensory and motor neurons in vivo. Consequently, expression of CMT2B mutants at levels between 0.5 and 10-fold their endogenous levels fully rescues the neuropathy-like phenotypes of the rab7 mutant. Live imaging reveals that CMT2B proteins are inefficiently recruited to endosomes, but do not impair endosomal maturation. These findings are not consistent with a gain-of-function mechanism. Instead, they indicate a dosage-dependent sensitivity of neurons to rab7-dependent degradation. Our results suggest a therapeutic approach opposite to the currently proposed reduction of mutant protein function.

DOI:http://dx.doi.org/10.7554/eLife.01064.001

Charcot-Marie-Tooth disease is an inherited disorder of the nervous system with symptoms that typically begin in adolescence or early adulthood. The sensory and motor nerves gradually degenerate, causing muscles to waste away and leading to the loss of touch sensation across the body. One subtype of the disease—Charcot-Marie-Tooth 2B—is caused by mutations in a gene called rab7, which codes for a protein that helps to regulate the breakdown of waste proteins inside cells.

Charcot-Marie-Tooth 2B is described as a genetically dominant disorder because all patients have one wild type copy and one mutant copy of the rab7 gene. Overexpression of the mutant gene in cells grown in culture alters many of the signaling pathways inside the cells, but it is unclear whether these alterations cause the pathology seen in the disease.

Now, Cherry et al. have obtained new insights into the genetics of Charcot-Marie-Tooth 2B by creating the first animal model of the disorder. Fruit flies that did not have the rab7 gene in the light-sensitive sensory neurons in their eyes were used to compare normal and mutant cells. While the two cell types were initially similar, the mutant cells gradually degenerated in the adult animal. By contrast, cells that overexpressed a mutant form of the rab7 gene continued to function normally throughout adulthood. Moreover, when mutant Rab7 proteins were introduced into the cells that lacked the rab7 gene, the proteins restored the cells’ sensitivity to light. These results suggest that mutant Rab7 proteins do not cause degeneration; instead, it is the loss of normal Rab7 function that causes problems.

At present, most research into treatment is aimed at finding ways to reduce the activity of mutant Rab7 proteins. However, the work of Cherry et al. suggests that increasing the activity of normal Rab7 proteins—or increasing the activity of alternative pathways that degrade waste proteins—may help to restore nerve function in this, and possibly other, neurodegenerative diseases.

DOI:http://dx.doi.org/10.7554/eLife.01064.002

Modelling the cost-effectiveness of carotid endarterectomy for asymptomatic stenosis5

Background

The aim of this study was to model the cost-effectiveness of carotid endarterectomy for asymptomatic stenosis versus medical therapy based on 10-year data from the Asymptomatic Carotid Surgery Trial (ACST).

Methods

This was a cost–utility analysis based on clinical effectiveness data from the ACST with UK-specific costs and stroke outcomes. A Markov model was used to calculate the incremental cost-effectiveness ratio (ICER, or cost per additional quality-of-life year) for a strategy of early endarterectomy versus medical therapy for the average patient and published subgroups. An exploratory analysis considered contemporary event rates.

Results

The ICER was £ 7584 per additional quality-adjusted life-year (QALY) for the average patient in the ACST. At thresholds of £ 20 000 and £ 30 000 there was a 74 and 84 per cent chance respectively of early endarterectomy being cost-effective. The ICER for men below 75 years of age was £ 3254, and that for men aged 75 years or above was £ 71 699. For women aged under 75 years endarterectomy was less costly and more effective than medical therapy; for women aged 75 years or more endarterectomy was less effective and more costly than medical therapy. At contemporary perioperative event rates of 2·7 per cent and background any-territory stroke rates of 1·6 per cent, early endarterectomy remained cost-effective.

Conclusion

In the ACST, early endarterectomy was predicted to be cost-effective in those below 75 years of age, using a threshold of £ 20 000 per QALY. If background any-territory stroke rates fell below 1 per cent per annum, early endarterectomy would cease to be cost-effective.

Two-year corneal cross-linking results in patients younger than 18 years with documented progressive keratoconus

PURPOSE

To report refractive, topographic, aberrometric, and tomographic outcomes 24 months after corneal cross-linking (CXL) in patients up to 18 years of age with progressive keratoconus.

DESIGN

Prospective, interventional case series.

METHODS

Forty eyes underwent riboflavin-ultraviolet A-induced CXL. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), sphere and cylinder, topography, aberrometry, tomography, and endothelial cell counts were evaluated at baseline and at 1, 3, 6, 12, and 24 months.

RESULTS

Mean logarithm of the minimum angle of resolution baseline UCVA and BSCVA were 0.79 ± 0.21 and 0.39 ± 0.10, respectively. Mean UCVA and BSCVA at 2 years were 0.58 ± 0.18 and 0.20 ± 0.09, respectively. The improvement in UCVA and BSCVA was significant throughout the postoperative follow-up (P < .05). Mean spherical equivalent refraction showed a significant decrease of 1.57 diopters (D) at 24 months (P = .02). Mean baseline simulated keratometry was 46.32 D in the flattest meridian and 51.48 D in the steepest meridian; at 2 years, the values were 45.30 D (P = .04) and 50.21 D (P = .07), respectively. For a 3-mm pupil, there was a significant reduction (P < .05) in whole eye (total), corneal, higher-order, and astigmatic wavefront aberrations at 24 months. A significant difference (P < .05) in total coma and total spherical aberration 2 years after CXL also was observed. Mean baseline pupil center pachymetry decreased significantly (P = .04) at 6 months, but recovered by 12 months and remained stable thereafter through the 2-year follow-up. Endothelial cell counts did not change significantly (P = .32).

CONCLUSIONS

CXL improved UCVA and BSCVA in the study patients, most likely by significantly reducing corneal asymmetry and corneal as well as total wavefront aberrations.

Low positive predictive value of the ABCD2 score in emergency department transient ischaemic attack diagnoses: the South Western Sydney transient ischaemic attack study

BACKGROUND

The ABCD(2) stroke risk score is recommended in national guidelines for stratifying care in transient ischaemic attack (TIA) patients, based on its prediction of early stroke risk. We had become concerned about the score accuracy and its clinical value in modern TIA cohorts.

METHODS

We identified emergency department-diagnosed TIA at two hospitals over 3 years (2004-2006). Cases were followed for stroke occurrence and ABCD(2) scores were determined from expert record review. Sensitivity, specificity and positive predictive values (PPV) of moderate-high ABCD(2) scores were determined.

RESULTS

There were 827 indexed TIA diagnoses and record review was possible in 95.4%. Admitted patients had lower 30-day stroke risk (n = 0) than discharged patients (n = 7; 3.1%) (P < 0.0001). There was no significant difference in proportion of strokes between those with a low or moderate-high ABCD(2) score at 30 (1.2 vs 0.8%), 90 (2.0 vs 1.9%) and 365 days (2.4 vs 2.4%) respectively. At 30 days the sensitivity, specificity and PPV of a moderate-high score were 57% (95% confidence interval (CI) 25.0-84.2), 32.2% (95% CI 29.1-35.6) and 0.75% (95% CI 0.29-1.91) respectively.

CONCLUSIONS

Early stroke risk was low after an emergency diagnosis of TIA and significantly lower in admitted patients. Moderate-high ABCD(2) scores did not predict early stroke risk. We suggest local validation of ABCD(2) before its clinical use and a review of its place in national guidelines.

Bevacizumab in combination with a taxane for the first-line treatment of HER2-negative metastatic breast cancer

This paper presents a summary of the evidence review group (ERG) report into the use of bevacizumab (Avastin®, Roche) in combination with a taxane for the treatment of untreated metastatic breast cancer (mBC). The main clinical effectiveness data were derived from a single, open-label randomised controlled trial (RCT) (E2100) that evaluated the addition of bevacizumab to weekly (q.w.) paclitaxel in patients with human epidermal growth factor receptor 2-negative mBC who had not previously received chemotherapy for advanced disease. This trial reported statistically significant increases in median progression-free survival (PFS) for the addition of bevacizumab (5.8-11.3 months). Median overall survival was not significantly different between the two groups; whether this is a true null finding or due to crossover between treatment arms cannot be established, as relevant data were not collected. The manufacturer reported that the addition of bevacizumab to paclitaxel q.w. therapy was associated with a significant improvement in quality of life, as measured by FACT-B (functional assessment of cancer therapy for breast cancer) scores. However, the ERG noted that these results were based on extreme imputed values, the removal of which led to non-significant differences in quality of life. The manufacturer conducted an indirect comparison. However, owing to methodological limitations and concerns about the validity and exchangeability of the included trials, the ERG did not consider the findings to be reliable. One additional relevant RCT [AVADO (Avastin and Docetaxel); BO17708] evaluating the addition of bevacizumab to docetaxel was excluded from the manufacturer's submission. This was summarised by the ERG. In terms of response rate and PFS, AVADO reported a markedly smaller benefit of adding bevacizumab to docetaxel than that reported for adding bevacizumab to q.w. paclitaxel in E2100. AVADO also reported no statistically significant effect of combination therapy versus docetaxel in terms of overall survival. The manufacturer developed a de novo economic model that considered patients with the same baseline characteristics as women in the E2100 trial. The model assessed BEV + PAC - bevacizumab 10 mg/kg every 2 weeks in combination with paclitaxel 90 mg/m2 weekly for 3 weeks followed by 1 week of rest; PAC q.w. - paclitaxel (monotherapy) 90 mg/m2 weekly for 3 weeks followed by 1 week of rest; DOC - docetaxel (monotherapy) 75 mg/m2 on day 1 every 21 days (considered current UK NHS clinical practice in the submission); and GEM + PAC - gemcitabine 1250 mg/m2 on days 1 and 8 plus paclitaxel 175 mg/m2 on day 1 every 21 days. Pairwise comparisons were made between BEV + PAC and PAC (using the E2100 trial), BEV + PAC and DOC, and BEV + PAC and GEM + PAC. Based on NHS list prices, the manufacturer's model estimated incremental cost-effectiveness ratios (ICERs) for BEV + PAC of £ 117,803, £ 115,059 and £ 105,777 per QALY gained, relative to PAC, DOC and GEM + PAC regimens, respectively. If the NHS Purchasing and Supply Agency prices for PAC with a 10-g cap on the cost per patient of BEV were used instead, the ICERs for BEV + PAC were estimated at £ 77,314, £ 57,753 and £ 60,101 per QALY, respectively. The submission suggested that the regimen of BEV + DOC is not cost-effective because it is considered less effective and more costly than BEV + PAC. Analysis by the ERG suggested that alternative assumptions can increase the ICERs further and, based on current prices, no plausible changes to the model assumptions will bring the ICERs for BEV + PAC lower.

Golimumab for the treatment of psoriatic arthritis

This paper presents a summary of the evidence review group (ERG) report into the use of golimumab for the treatment of psoriatic arthritis (PsA). The main clinical effectiveness data were derived from a single phase III randomised controlled trial (RCT: GO-REVEAL) that compared golimumab with placebo for treating patients with active and progressive PsA who were symptomatic despite the use of previous disease-modifying antirheumatic drugs or non-steroidal anti-inflammatory drugs. The 14-week data showed that, compared with placebo, golimumab 50 mg significantly improved joint disease response as measured by American College of Rheumatology (ACR) 20 [relative risk (RR) 5.73, 95% confidence interval (CI) 3.24 to 10.56] and Psoriatic Arthritis Response Criteria (PsARC) (RR 3.45, 95% CI 2.49 to 4.87), and skin disease response as measured by the Psoriasis Area and Severity Index (PASI) 75 (RR 15.95, 95% CI 4.62 to 59.11). The 24-week absolute data showed that these treatment benefits were maintained. There was a significant improvement in patients' functional status as measured by the Health Assessment Questionnaire (HAQ) change from baseline at 24 weeks (-0.33, p < 0.001). The open-label extension data showed that these beneficial effects were also maintained at 52 and 104 weeks. However, PASI 50 and PASI 90 at 14 weeks, and all of the PASI outcomes at 24 weeks, were not performed on the basis of intention-to-treat analysis. Furthermore, analyses of the 24-week data were less robust, failing to adjust for treatment contamination due to patient crossover at week 16. The manufacturer conducted a mixed treatment comparison (MTC) analysis. The ERG considered the assumption of exchangeability between the trials for the purpose of the MTC analysis to be acceptable, and the statistical approach in the MTC analysis to be reliable. Regarding the safety evaluation of golimumab, the manufacturer failed to provide longer-term data or to consider adverse event data of golimumab from controlled studies in other conditions, such as rheumatoid arthritis and ankylosing spondylitis. Although the adverse effect profile of golimumab appears similar to other anti-tumour necrosis factor (TNF) agents, the longer-term safety profile of golimumab remains uncertain. The manufacturer's submission presented a decision model to compare etanercept, infliximab, golimumab and adalimumab versus palliative care for patients with PsA. In the base-case model, 73% of the cohort of patients were assumed to have significant psoriasis (> 3% of body surface area). Estimates of the effectiveness of anti-TNF agents in terms of PsARC, HAQ change and PASI change were obtained from an MTC analysis of RCT data. The manufacturer failed to calculate incremental cost-effectiveness ratios (ICERs) correctly by comparing golimumab with palliative care instead of the most cost-effective alternative (etanercept). Despite the manufacturer's claim that golimumab is a cost-effective treatment option, the manufacturer's own model showed that golimumab is not cost-effective compared with other biologics when the ICERs are correctly calculated. None of the sensitivity analyses carried out by the manufacturer or the ERG regarding uncertainty in the estimates of clinical effectiveness, the acquisition and administration cost of drugs, the cost of treating psoriasis and the utility functions estimated to generate health outcomes changed this conclusion. However, a key area in determining the cost-effectiveness of anti-TNF agents is whether they should be treated as a class. If all anti-TNF agents are considered equally effective then etanercept, adalimumab and golimumab have very nearly equal costs and equal quality-adjusted life-years (QALYs), and all have an ICER of about £ 15,000 per QALY versus palliative care, whereas infliximab with a higher acquisition cost is dominated by the other biologics.

Prospective study of foveal thickness alterations after cataract surgery assessed by optical coherence tomography

BACKGROUND/AIMS

To evaluate the alterations of mean foveal thickness (MFT) and visual acuity (VA) outcomes after uncomplicated cataract surgery in different groups of patients.

METHODS

This study included eyes of consecutive patients who underwent cataract surgery between November 2007 and June 2009. The patients included in the study were divided into 4 groups, as follows: history-free patients, patients with diabetes mellitus without macular involvement at baseline, patients with glaucoma, and patients with epiretinal membrane (ERM). Preoperatively and at 1, 3 and 6 months postoperatively, patients were evaluated for MFT by optical coherence tomography at the central 1-mm macular zone and for logarithm of the minimum angle of resolution best spectacle-corrected VA (BSCVA).

RESULTS

A total of 202 eyes were included in the study. MFT values demonstrated a statistically significant increase (p < 0.01) after cataract surgery in all groups at the first and third postoperative month. The history-free (p = 0.09) and glaucoma (p = 0.19) groups did not demonstrate a statistically significant difference in MFT values between the preoperative and 6-month measurements. MFT values 6 months after cataract surgery in the diabetes and ERM groups remained significantly higher (p < 0.01). Despite these findings, VA increased significantly (p < 0.01) in all groups at all postoperative follow-ups.

CONCLUSIONS

MFT values increased significantly in all groups at the first and third months after cataract surgery. At 6 months, MFT values returned to preoperative levels in the history-free and glaucoma patients, while they remained significantly higher in the diabetic and ERM patients. Despite these macular alterations, BSCVA improved significantly after cataract surgery in all groups at all postoperative follow-ups.

The synaptic vesicle SNARE neuronal Synaptobrevin promotes endolysosomal degradation and prevents neurodegeneration

The synaptic v-SNARE n-Syb functions not only in synaptic vesicle exocytosis but also in delivery of protein-degrading enzymes to endosomes that are necessary to prevent protein aggregation and neurodegeneration.

Soluble NSF attachment protein receptors (SNAREs) are the core proteins in membrane fusion. The neuron-specific synaptic v-SNARE n-syb (neuronal Synaptobrevin) plays a key role during synaptic vesicle exocytosis. In this paper, we report that loss of n-syb caused slow neurodegeneration independent of its role in neurotransmitter release in adult Drosophila melanogaster photoreceptor neurons. In addition to synaptic vesicles, n-Syb localized to endosomal vesicles. Loss of n-syb lead to endosomal accumulations, transmembrane protein degradation defects, and a secondary increase in autophagy. Our evidence suggests a primary defect of impaired delivery of vesicles that contain degradation proteins, including the acidification-activated Cathepsin proteases and the neuron-specific proton pump and V0 adenosine triphosphatase component V100. Overexpressing V100 partially rescued n-syb–dependent degeneration through an acidification-independent endosomal sorting mechanism. Collectively, these findings reveal a role for n-Syb in a neuron-specific sort-and-degrade mechanism that protects neurons from degeneration. Our findings further shed light on which intraneuronal compartments exhibit increased or decreased neurotoxicity.

Intracellular trafficking in Drosophila visual system development: a basis for pattern formation through simple mechanisms

Intracellular trafficking underlies cellular functions ranging from membrane remodeling to receptor activation. During multicellular organ development, these basic cell biological functions are required as both passive machinery and active signaling regulators. Exocytosis, endocytosis, and recycling of several key signaling receptors have long been known to actively regulate morphogenesis and pattern formation during Drosophila eye development. Hence, intracellular membrane trafficking not only sets the cell biological stage for receptor-mediated signaling but also actively controls signaling through spatiotemporally regulated receptor localization. In contrast to eye development, the role of intracellular trafficking for the establishment of the eye-to-brain connectivity map has only recently received more attention. It is still poorly understood how guidance receptors are spatiotemporally regulated to serve as meaningful synapse formation signals. Yet, the Drosophila visual system provides some of the most striking examples for the regulatory role of intracellular trafficking during multicellular organ development. In this review we will first highlight the experimental and conceptual advances that motivate the study of intracellular trafficking during Drosophila visual system development. We will then illuminate the development of the eye, the eye-to-brain connectivity map and the optic lobe from the perspective of cell biological dynamics. Finally, we provide a conceptual framework that seeks to explain how the interplay of simple genetically encoded intracellular trafficking events governs the seemingly complex cellular behaviors, which in turn determine the developmental product.