Nucleophilic Reactivity at a ═CH Arm of a Lutidine-Based CNC/Rh System: Unusual Alkyne and CO2 Activation

Reaction of an amido pincer complex [(CNC)*Rh(CO)] (1) (CNC* is the deprotonated form of CNC) with carbon dioxide gave a neutral complex [(CNC-CO₂)^Mes*Rh(CO)] (2), which is the result of a C-C bond-forming reaction between the deprotonated arm of the CNC* ligand and CO₂. The molecular structure of 2 showed a zwitterionic complex, where the CO₂ moiety is covalently connected to the former ═CH arm of the CNC* pincer ligand. The unusual structure of 1 allowed us to explore the reactivity of the CO₂ moiety with selected primary amines RNH₂ (benzylamine and ammonia), which afforded cationic complexes [(CNC)^MesRh(CO)][HRNC(O)O] (R = Bz (3), H (4)). Compounds 3 and 4 are the result of a C-N coupling between the incoming amine and the CO₂ fragment covalently connected to the pincer ligand in 2, a process that involves protonation of the "CH-CO₂" fragment in 2 from the respective amines. Once revealed the nucleophilic character of the ═CH fragment in 1, we explored its reactivity with alkynes, a study that enlightened a novel reactivity trend in alkyne activation. Reaction of 1 with terminal alkynes RC≡CH (R = Ph, 2-py, 4-C₆H₄-CF₃) yielded neutral complexes [(CNC-CH═CHR)^Mes*Rh(CO)] (R = Ph (5), 2-py (6), 4-C₆H₄-CF₃ (7)) in good yields. Deuterium labeling experiments with PhC≡CD confirmed that complex 5 is the product of a formal insertion of the alkyne into the C(sp²)-H bond of the deprotonated arm in 1. This structural proposal was further confirmed by the X-ray molecular structure of phenyl complex 5, which showed the alkyne covalently linked to the pincer ligand. Besides, this novel transformation was analyzed by DFT methods and showed a metal-ligand cooperative mechanism, based on the initial electrophilic attack of the alkyne to the ═CH arm of the CNC^Mes* ligand (making a new C-C bond) followed by the action of a protic base (HN(SiMe₃)₂), which is able to perform a proton rearrangement that leads to the final product 5.

Efficient solventless dehydrogenation of formic acid by a CNC-based rhodium catalyst

A CNC based rhodium complex is an efficient catalyst for formic acid dehydrogenation under solventless conditions.

Optimal treatment sequencing of abiraterone acetate plus prednisone and enzalutamide in patients with castration-resistant metastatic prostate cancer: A systematic review and meta-analysis

PURPOSE

To evaluate the impact of the hormonal treatment sequencing including abiraterone acetate plus prednisone (AAP) and enzalutamide (ENZ) in mCRPC, and determine which sequence provides more benefits for patients.

METHODS

Studies published in English between 1 January 2013 and 30 September 2017 were identified in PubMed and EMBASE electronic databases. Studies assessing the efficacy of treatment sequences, based on AAP and ENZ, in mCRPC patients, were eligible for analysis.

RESULTS

Seventeen studies met the inclusion criteria. Two assessed both treatment sequences AAP → ENZ and ENZ → AAP; it was found that sequence of AAP → ENZ showed a statistically significantly longer PSA-PFS than the observed in ENZ → AAP (pooled HR: 0,54; 95% CI; 0,36-0,82; p < 0,05). The nine studies analysing Doc → AAP → ENZ sequence, revealed favourable results in terms of PFS. The 5 studies which analysed AAP → ENZ sequence, show a decrease in PSA levels ≥ 50% in 11-41% of patients treated with enzalutamide after previous treatment with AAP. In the two studies that analysed the Doc → ENZ → AAP sequence, PSA response rates were much lower than those reported with Doc → AAP → ENZ, with decreases in PSA ≥ 30 of 3-18% and PSA ≥ 50 of 8-11%.

CONCLUSION

Significant clinical efficacy of AAP administered as the first-line treatment in mCRPC patients followed by enzalutamide, delaying disease progression, compared with the ENZ → AAP sequence. However, more studies and randomized trials are needed, to validate the best treatment sequencing.

Cost-effectiveness analysis of chronic hepatitis C treatment in the prison population in Spain

Objectives

To evaluate the cost-effectiveness of direct-acting antiviral (DAAs) treatment versus non-treatment in prisoners awaiting treatment for chronic hepatitis C (CHC) and to analyse the clinical and economic impact of the treatment on liver complications and mortality.

Material and method

A lifetime Markov model was developed to simulate treatment and disease progression from an estimated cohort of 4,408 CHC prisoners treated with DAAs over 2 years (50% of patient each year) versus no treatment. In the treated cohort, a sustained viral response of 95% was associated. Patient characteristics, transition probabilities, utilities and costs (pharmacological and healthcare states) were obtained from published literature. The model estimated healthcare costs and benefits, incremental cost-utility ratio (ICUR) based on total costs and the quality-adjusted life year (QALY) and avoided clinical events. A National Healthcare System perspective was adopted with a 3% annual discount rate for both costs and health outcomes. Sensitivity analyses were performed to assess uncertainty.

Results

In the DDA treated cohort, the model estimated a decrease of 92% of decompensated cirrhosis and 83% of hepatocellular carcinoma, 88% liver-related mortality cases were reduced, 132 liver transplants were avoided. The treatment achieved an additional 5.0/QALYs (21.2 vs. 16.2) with an incremental cost of €3,473 (€24,088 vs. €20,615) per patient with an ICUR of €690 per QALY gained.

Discussion

Considering the willingness-to-pay threshold used in Spain (€22,000-30,000/QALY), DAAs treatment for prisoners with CHC is a highly cost-effective strategy, reduces infection transmission, increases survival and reduces complications due to liver disease, as well as the cost associated with its management.

Is the universal population Hepatitis C virus screening a cost-effective strategy? A systematic review of the economic evidence

Background

Efficient strategies are needed in order to achieve the objective of the WHO of eradicating Hepatitis C virus (HCV). Hepatitis C infection can be eliminated by a combination of direct acting antiviral (DAA). The problem is that many individuals remain undiagnosed. The objective is to conduct a systematic review of the evidence on economic evaluations that analyze the screening of HCV followed by treatment with DAAs.

Methods

Eleven databases were performed in a 2015-2018-systematic review. Inclusion criteria were economic evaluations that included incremental cost-effectiveness ratio (ICER) in terms of cost per life year gained or quality-adjusted life year.

Results

A total of 843 references were screened. Sixteen papers/posters meet the inclusion criteria. Ten of them included a general population screening. Other populations included were baby-boomer, people who inject drugs, prisoners or immigrants. Comparator was “standard of care”, other high-risk populations or no-screening. Most of the studies are based on Markov model simulations and they mostly adopted a healthcare payer´s perspective. ICER for general population screening plus treatment versus high-risk populations or versus routinely performed screening showed to be below the accepted willingness to pay thresholds in most studies and therefore screening plus DAAs strategy is highly cost-effective.

Conclusion

This systematic review shows that screening programmes followed by DAAs treatment is cost-effective not only for high risk population but for general population too. Because today HCV can be easily cured and its long-term consequences avoided, a universal HCV screening plus DAAs therapies should be the recommended strategy to achieve the WHO objectives for HCV eradication by 2030.

P3815Cost and burden of poor control of the level of anticoagulation in patients with non-valvular atrial fibrillation treated with vitamin K antagonist in the Spanish National Health Service

Introduction

Poorly controlled non-valvular atrial fibrillation (NVAF) patients treated with vitamin K antagonists (VKA) experience higher rates of clinical events compared to well controlled patients. In Spain a high percentage of NVAF patients present an inadequate control of anticoagulation therapy, whose economic impact has not been reported yet.

Purpose

To estimate the impact on resource consumption, clinical events and mortality of poorly controlled NVAF patients≥65 years treated with VKA in Spain.

Methods

A cost-consequence analytic model was developed to estimate differences on clinical events and cost between poorly controlled (TTR<65%) and well controlled (TTR≥65%) NVAF patients treated with VKA over 1 year. A hypothetical cohort of NVAF patients was estimated by using local epidemiological studies. Anticoagulation control rates, as measured by Rosendaal method, were retrieved from a literature review of Spanish real-world studies.

Clinical event rates (ischemic stroke-IS-, hemorrhagic stroke-HS-, major bleeding-MB-, systemic embolism-SE- and death for any cause) were derived from a post-hoc analysis of SPORTIF III/V trials. A sensitivity analysis (SA) was performed by using event rates from a prospective single-center study carried out in Spain.

Societal and National Health Service (NHS) perspectives were considered. Total annual costs (€ 2018) included clinical event direct, non-direct healthcare cost and indirect-costs. Potential life years lost (PLYL) were calculated to report impact on mortality. An expert panel composed by a cardiologist, a haematologist and general practitioners validated the model inputs.

Results

The target population comprised 594,855 NVAF patients treated with VKA (mean age 73.2 years, 49.4% women, 74.1% CHADS≥2). Poorly controlled anticoagulated patients accounted for 48.3% of the cohort. The inadequate control of anticoagulation was associated with a higher incidence of clinical events compared to well controlled patients within a year (additional 2,143 IS, 390 HS, 201 SE, 6,190 MB and 6,856 deaths). From NHS perspective, the incremental total annual costs associated to poorly controlled patients were €46,685,756.60 (€173.96/patient-year). When considering the societal perspective, the incremental total annual costs of inadequate anticoagulation control reached €97,787,872.59 (€367.51/patient-year). Mortality due to poorly anticoagulation control implied 80,830.65 PLYL (0.136 PLYL/patient-year). The SA confirmed the base case results.

Conclusions

In the Spanish NHS, around 50% of NVAF patients ≥65 years treated with VKA present an inadequate control of the anticoagulation therapy (287,089 patients), which is associated with the increase of clinical events, mortality and costs (up to €100 million). The results of this study highlight a call to action to increase the awareness of the consequences of a poor anticoagulation control and emphasize the need for a better clinical of patients receiving anticoagulation.

Acknowledgement/Funding

BMS and PFIZER contributed to finance the no conditioned to the results of this work.

Real World Patient-reported Outcomes in HIV-infected Adults Switching to EVIPLERA®, Because of a Previous Intolerance to cART. PRO-STR Study

Background:

To investigate the impact of switching from stable Combined Antiretroviral Therapy (cART) to single-tablet regimen (RPV/FTC/TDF=EVIPLERA®/COMPLERA®) on patient-reported outcomes in HIV-infected adults who cannot tolerate previous cART, in a real-world setting.

Methods:

PRO-STR is a 48-week observational, prospective, multicenter study. Presence and magnitude of symptoms (main endpoint), health-related quality-of-life (HRQoL), adherence, satisfaction with treatment and patient preferences were assessed.

Results:

Three hundred patients with 48-week follow-up, who switched to EVIPLERA® (mean age: 46.6 years; male: 74.0%; 74.7% switched from a non-nucleoside reverse-transcriptase-inhibitor, 25.3% from a protease inhibitor + ritonavir) were included. There was no statistical difference in median CD4+ cell count (baseline: 678.5 cells/mm3; 48-week: 683.0 cells/mm3) neither in virological suppression (≤50 copies/mL) (baseline: 98.3%; 48-week: 95.3%). The most frequent reasons for switching were neuropsychiatric (62.3%), gastrointestinal (19.3%) and biochemical/metabolic (19.3%) events. Only 7.7% of patients permanently discontinued therapy. At 48-week, all outcomes showed an improvement compared to baseline. Overall, there was a significant decrease (p-value≤0.05) in number and magnitude of symptoms, while HRQoL, satisfaction and adherence improved significantly. Most patients prefered EVIPLERA® than previous cART. According to the type of intolerance, HRQoL was improved, but only significantly in patients with neuropsychiatric and gastrointestinal symptoms. Adherence improved significantly in patients with metabolic disturbances and satisfaction with EVIPLERA® was higher in the three groups.

Conclusion:

Switching to EVIPLERA® from non-nucleoside reverse-transcriptase-inhibitor or protease inhibitor-based regimens due to toxicity, improved the presence/magnitude of symptoms, HRQoL, and preference with treatment. EVIPLERA® maintained a virological response, CD4+ cell count and maintained or improved adherence.

Systematic review of the evidence on the epidemiology of herpes zoster: incidence in the general population and specific subpopulations in Spain

OBJECTIVES

Herpes zoster (HZ) is an important cause of morbidity around the world, especially among the adult population aged >50 years.

STUDY DESIGN

A systematic review of the literature (up to October 31, 2016) was performed to identify available evidence on incidence of HZ in the general population and in a specific subpopulation in Spain.

METHODS

PubMed and Embase databases were searched, combining the following search terms: 'herpes zoster', 'diabetes mellitus (DM)', 'chronic obstructive pulmonary disease (COPD)', 'chronic heart failure', 'mental disorders' and 'immunocompromised'. Supplements for local scientific congresses, non-indexed Spanish journals and official epidemiological reports, potentially HZ related, were also manually searched. The inclusion criteria were the following: English or Spanish publications reporting incidence of HZ in the Spanish general population and/or specific subpopulations. No restrictions were applied on the study design or population age.

RESULTS

Among 269 references retrieved (48 PubMed, 148 Embase and 73 manual searching), 34 were finally included. Incidence of HZ in the general population ranged from 2.1 to 5.5/1000 person-years. HZ incidence ranged from 9.4 to 15.3/1000 patients with DM and from 11.0 to 11.4/1000 population with COPD or cardiovascular disease. In asthmatic patients, 6.9 HZ cases/1000 subjects were reported. The highest HZ incidence (1.3-400.0/1000 person-years) was in immunocompromised persons (10.0/1000 patients with cancer, 12.5/1000 patients with AIDS, from 5.0 to 240.0/1000 transplanted patients and from 6.6 to 27.0/1000 population with rheumatic diseases). Three studies estimated an increased risk of HZ in comparison with general population, for patients with DM (24%), COPD (39%) and COPD receiving inhaled corticosteroids (61%).

CONCLUSIONS

The results suggest a high risk of HZ in certain age groups and specific subpopulations. This study could contribute to identify target age populations and at-risk groups if implementation of HZ vaccination programmes in Spain would be considered.

Variation in phenology and overall performance traits can help to explain the plant invasion process amongst Mediterranean ecosystems

Plant traits such as phenological development, growth rate, stress tolerance and seeds production may play an important role in the process of acclimatisation to new environments for introduced plants. Experiments that distinguish phenotypic plasticity from ecotypic differentiation would allow an understanding of the role of plant traits in the invasion process. We quantified the variation in phenological and overall performance traits associated with the invasion process for three herbaceous species native to Spain and invasive to Chile (Trifoliumglomeratum, Hypochaerisglabra and Leontodonsaxatilis). We grew plants from native and exotic populations along rainfall gradients in outdoor common gardens, located in the native and the introduced ranges and measured plant survival, phenology (days to flowering), biomass and seed output. Days to flowering was positively correlated with precipitation of the origin population for T.glomeratum and the native populations of H.glabra, but this pattern was not adaptive, as it was not associated with an increase in performance traits of these species. Phenology may instead reflect ecotypic differentiation to the environmental conditions of the original populations. Comparison between ranges (i.e. performance in both common gardens) was only possible for L.saxatilis. This species showed little variation in phenology and both native and exotic populations had higher fitness in the introduced range. This suggests that plasticity enhances invasiveness through increased propagule pressure in the novel environment. Our findings highlight the utility of common garden experiments in examining patterns of phenological and performance traits that relate to species invasiveness.

Asymmetric flows and drivers of herbaceous plant invasion success among Mediterranean-climate regions

Understanding the mechanisms that support the arrival, establishment and spread of species over an introduced range is crucial in invasion ecology. We analysed the unintentionally introduced herbaceous species that are naturalised in the five Mediterranean-climate regions. There is an asymmetry in the species flows among regions, being the Iberian Peninsula the main donor to the other regions. At interregional scale, the species’ capacity to spread among regions is related to the ecological versatility of the species in the donor area (Iberian Peninsula). At intraregional scale, the species’ capacity to successfully occupy a complete region first depends on the time elapsed from its introduction and afterwards on the degree of occurrence in the region of origin, which is commonly related to its chance of coming into contact with humans. Information on exotic species in their origin region provides insights into invasion process and decision-making to reduce the risks of future invasions.

The invasiveness of Hypochaeris glabra (Asteraceae): Responses in morphological and reproductive traits for exotic populations

Scientists have been interested in many topics driven by biological invasions, such as shifts in the area of distribution of plant species and rapid evolution. Invasiveness of exotic plant species depends on variations on morphological and reproductive traits potentially associated with reproductive fitness and dispersal ability, which are expected to undergo changes during the invasion process. Numerous Asteraceae are invasive and display dimorphic fruits, resulting in a bet-hedging dispersal strategy –wind-dispersed fruits versus animal-dispersed fruits–. We explored phenotypic differentiation in seed morphology and reproductive traits of exotic (Chilean) and native (Spanish) populations of Hypochaeris glabra. We collected flower heads from five Spanish and five Chilean populations along rainfall gradients in both countries. We planted seeds from the ten populations in a common garden trial within the exotic range to explore their performance depending on the country of origin (native or exotic) and the environmental conditions at population origin (precipitation and nutrient availability). We scored plant biomass, reproductive traits and fruit dimorphism patterns. We observed a combination of bet-hedging strategy together with phenotypic differentiation. Native populations relied more on bet-hedging while exotic populations always displayed greater proportion of wind-dispersed fruits than native ones. This pattern may reflect a strategy that might entail a more efficient long distance dispersal of H. glabra seeds in the exotic range, which in turn can enhance the invasiveness of this species.

Local plant responses to global problems: Dactylis glomerata responses to different traffic pollutants on roadsides

The growing number of road vehicles is a major source of regional and global atmospheric pollution increasing concentrations of CO₂ in the air, and levels of metals in air and soil. Nevertheless, the effects of these pollutants on plants growing at roadsides are poorly documented. We carried out an observational study of unmanipulated plants growing by the road, to identify the morpho-physiological responses in a perennial grass Dactylis glomerata. Firstly, we wanted to know the general effect of traffic intensity and ambient CO₂ and its interactions on different plant traits. Accordingly, we analyzed the photosynthetic response by field A/Ci Response Curves, SLA, pigment pools, foliar nitrogen, carbohydrates and morphological traits in plants at three distances to the road. Secondly, we wanted to know if Dactylis glomerata plants can accumulate metals present on the roadside (Pb, Zn, Cu, and Sr) in their tissues and rhizosphere, and the effect of these metals on morphological traits. The MANCOVA whole model results shown: 1) a significant effect of road ambient CO₂ concentration on morphological traits (not affected by traffic intensity, P _{interaction CO2 x traffic intensity}>0.05), that was mainly driven by a significant negative relationship between the inflorescence number and ambient CO₂; 2) a positive and significant relationship between ambient CO₂ and the starch content in leaves (unaffected by traffic intensity); 3) a reduction in J_max (electron transport rate) at high traffic intensity. These lines of evidences suggest a decreased photosynthetic capacity due to high traffic intensity and high levels of ambient CO₂. In addition, Pb, Cu, Zn and Sr were detected in Dactylis glomerata tissues, and Cu accumulated in roots. Finally, we observed that Dactylis glomerata individuals growing at the roadside under high levels of CO₂ and in the presence of metal pollutants, reduced their production of inflorescences.

Understanding the reaction mechanism of the oxidative addition of ammonia by (PXP)Ir(i) complexes: the role of the X group

An analysis of the electronic rearrangements for the oxidative addition of ammonia to a set of five representative (PXP)Ir pincer complexes (X = B, CH, O, N, SiH) is performed. We aim to understand the factors controlling the activation and reaction energies of this process by combining different theoretical strategies based on DFT calculations. Interestingly, complexes featuring higher activation barriers yield more exothermic reactions. The analysis of the reaction path using the bonding evolution theory shows that the main chemical events, N-H bond cleavage and Ir-H bond formation, take place before the transition structure is reached. Metal oxidation implies an electron density transfer from non-shared Ir pairs to the Ir-N bond. This decrement in the atomic charge of the metal provokes different effects in the ionic contribution of the Ir-X bonding depending on the nature of the X atom as shown by the interacting quantum atoms methodology.

Cost-Effectiveness and Clinical Impact of Antiviral Strategies of HBeAg-Positive and -Negative Chronic Hepatitis B

INTRODUCTION

Chronic hepatitis B (CHB) is associated with high burden and healthcare costs. Virologic response achieved with antivirals is associated with progression avoidance. This study aimed to estimate the efficiency and clinical impact of antiviral strategies in CHB patients.

MATERIAL AND METHODS

A Markov model estimated lifetime complications and direct costs in both, HBeAg-positive and HBeAg-negative cohorts. Strategy 1 (71% of treated population) and strategy 2 (100%), both based on pegylated interferon (peg-IFN) followed by oral tenofovir or entecavir, were compared to no treatment. Progression was based on HBV-DNA levels. Rescue therapy with oral antivirals was applied for peg-IFN failure. Disease costs (C, 2014) and utilities were obtained from literature.

RESULTS

Compared to natural history, strategy 1 increased QALY (3.98 in HBeAg-positive, 2.16 in -negative cohort). With strategy 2, survival was up to 5.60 (HBeAg-positive) and 3.05 QALY (in HBeAg-negative). The model predicted avoidance of 128 and 86 carcinomas in HBeAg-positive and -negative patients with strategy 1, and up to 181 and 121 in HBeAg-positive and -negative for strategy 2. Total cost increased up to C102,841 (strategy 1) and C105,408 (strategy 2) in HBeAg-positive, and C85,858 and C93,754 in HBeAg-negative. A C1,581/QALY gained ratio was estimated versus the natural history for both strategies. In conclusion, increasing antiviral coverage would be efficient, reducing complications.

Cost-effectiveness analysis of ledipasvir/sofosbuvir in patients with chronic hepatitis C: Treatment of patients with absence or mild fibrosis compared to patients with advanced fibrosis

To evaluate the cost-effectiveness of ledipasvir/sofosbuvir (LDV/SOF) in treatment-naïve patients with chronic hepatitis C (CHC) genotype 1 (GT1) in the absence or mild fibrosis (F0-F1) versus advanced fibrosis (F2-F4), from the perspective of the Spanish Health System. A Markov model was developed to simulate disease progression, estimating costs and outcomes [life years gained (LYG) and quality-adjusted life years (QALY)] derived from starting with LDV/SOF in patients with F0-F1 compared with F2-F4. Therapy duration was 8 weeks in noncirrhotic patients with viral load <6 million IU/mL and 12 weeks in the remaining patients. Sustained virologic response rates were obtained from real-world cohort studies. Transition probabilities, utilities and direct costs were obtained from the literature. A 3% annual discount rate was applied to costs and outcomes. Sensitivity analyses were performed. LDV/SOF in F0-F1 patients was a dominant strategy, being more effective (19.85 LYG and 19.80 QALY) than beginning treatment in F2-F4 patients (18.63 LYG and 16.25 QALY), generating savings of €9228 per patient (€3661 due to disease management and monitoring). In a cohort of 1000 patients, LDV/SOF in F0-F1 patients decreased the number of cases of decompensated cirrhosis (93%), hepatocellular carcinoma (97%) and liver-related deaths (95%) and prevented 6 liver transplants compared to initiating LDV/SOF in F2-F4 patients. In CHC treatment-naïve GT1 patients, starting treatment with LDV/SOF in patients with F0-F1 compared to those with F2-F4 increases effectiveness by 1.22 LYG and 3.55 QALY gained and reduces disease burden and it is associated with cost savings.

Reactivity of the parent amido complexes of iridium with olefins: C-NH2 bond formation versus C-H activation

Herein we report on the different chemical reactivity displayed by two mononuclear terminal amido compounds depending on the nature of the coordinated diene. Hence, treatment of amido-bridged iridium complexes [{Ir(μ-NH₂)(tfbb)}₃] (1; tfbb = tetrafluorobenzobarrelene) with dppp (dppp = bis(diphenylphosphane)propane) leads to the rupture of the amido bridges forming the mononuclear terminal amido compound [Ir(NH₂)(dppp)(tfbb)] (3) in the first stage. On changing the reaction conditions, the formation of a C-NH₂ bond between the amido moiety and the coordinated diene is observed and a new dinuclear complex [{Ir(1,2-η²-4-κ-C₁₂H₈F₄N)(dppp)}₂(μ-dppp)] (4) has been isolated. On the contrary, the diiridium amido-bridged complex [{Ir(μ-NH₂)(cod)}₂] (2; cod = 1,5-cyclooctadiene) in the presence of dppb (dppb = bis(diphenylphosphane)butane) allows the isolation of a mononuclear complex [Ir(1,2,3-η³-6-κ-C₈H₁₀)H(dppb)] (5), as a consequence of the extrusion of ammonia. The monitoring of the reaction of 2 with dppb (and dppp) allowed us to detect terminal amido complexes [Ir(NH₂)(P-P)(cod)] (P-P = dppb (6), dppp (7)) in solution, as confirmed by an X-ray analysis of 7. Complex 7 was observed to evolve into hydrido species 5 at room temperature. DFT studies showed that C-H bond activation occurs through the deprotonation of one methylene fragment of the cod ligand by the highly basic terminal amido moiety instead of C-H oxidative addition to the Ir(i) center.

Ecotypic differentiation and phenotypic plasticity combine to enhance the invasiveness of the most widespread daisy in Chile, Leontodon saxatilis

Dispersal and reproductive traits of successful plant invaders are expected to undergo strong selection during biological invasions. Numerous Asteraceae are invasive and display dimorphic fruits within a single flower head, resulting in differential dispersal pathways - wind-dispersed fruits vs. non-dispersing fruits. We explored ecotypic differentiation and phenotypic plasticity of seed output and fruit dimorphisms in exotic Chilean and native Spanish populations of Leontodon saxatilis subsp. rothii. We collected flower heads from populations in Spain and Chile along a rainfall gradient. Seeds from all populations were planted in reciprocal transplant trials in Spain and Chile to explore their performance in the native and invasive range. We scored plant biomass, reproductive investment and fruit dimorphism. We observed strong plasticity, where plants grown in the invasive range had much greater biomass, flower head size and seed output, with a higher proportion of wind-dispersed fruits, than those grown in the native range. We also observed a significant ecotype effect, where the exotic populations displayed higher proportions of wind-dispersed fruits than native populations. Together, these patterns reflect a combination of phenotypic plasticity and ecotypic differentiation, indicating that Leontodon saxatilis has probably increased propagule pressure and dispersal distances in its invasive range to enhance its invasiveness.

Real-world cost-effectiveness of infliximab, etanercept and adalimumab in rheumatoid arthritis patients: results of the CREATE registry

Biological drugs have proven efficacy and effectiveness in treatment of rheumatoid arthritis (RA), although none has been shown to be superior. Few studies have evaluated the cost-effectiveness of biological drugs in real-life clinical conditions. The objective of this study was to compare the cost-effectiveness of infliximab, etanercept and adalimumab in achieving clinical remission (DAS28 < 2.6) when used as initial biological therapy. Patients were diagnosed with RA who began treatment with infliximab, etanercept or adalimumab in the Reina Sofia Hospital (Cordoba, Spain) between January 1, 2007, and December 31, 2012. Effectiveness was measured as the percentage of patients who achieved clinical remission after 2 years. The cost analysis considered the use of direct health resources (perspective of the healthcare system). Cost-effectiveness was calculated by dividing the total mean cost of each treatment by the percentage of patients who achieved remission. One hundred and thirty patients were included: 55 with infliximab, 44 with adalimumab and 31 with etanercept. After 2 years, 45.2 % of patients with adalimumab achieved clinical remission, versus 29.1 % with infliximab (p = 0.133) and 22.7 % with etanercept (p = 0.040), with no differences between etanercept and infliximab (p = 0.475). The average total cost at 2 years was €29,858, €25,329 and €23,309 for adalimumab, infliximab and etanercept, respectively, while the mean cost (95 %CI) to achieve remission was €66,057 (48,038–84,076), €87,040 (78,496–95,584) and €102,683 (94,559–110,807), respectively. Adalimumab was more efficient than etanercept (p < 0.001) and infliximab (p = 0.026), with no differences between etanercept and infliximab (p = 0.086). Adalimumab was the most cost-effective treatment in achieving clinical remission in real-life clinical conditions in RA patients during the study period.

Nucleophilicity and P-C Bond Formation Reactions of a Terminal Phosphanido Iridium Complex

The diiridium complex [{Ir(ABPN2)(CO)}2(μ-CO)] (1; [ABPN2](-) = [(allyl)B(Pz)2(CH2PPh2)](-)) reacts with diphenylphosphane affording [Ir(ABPN2)(CO)(H) (PPh2)] (2), the product of the oxidative addition of the P-H bond to the metal. DFT studies revealed a large contribution of the terminal phosphanido lone pair to the HOMO of 2, indicating nucleophilic character of this ligand, which is evidenced by reactions of 2 with typical electrophiles such as H(+), Me(+), and O2. Products from the reaction of 2 with methyl chloroacetate were found to be either [Ir(ABPN2)(CO)(H)(PPh2CH2CO2Me)][PF6] ([6]PF6) or [Ir(ABPN2)(CO)(Cl)(H)] (7) and the free phosphane (PPh2CH2CO2Me), both involving P-C bond formation, depending on the reaction conditions. New complexes having iridacyclophosphapentenone and iridacyclophosphapentanone moieties result from reactions of 2 with dimethyl acetylenedicarboxylate and dimethyl maleate, respectively, as a consequence of a further incorporation of the carbonyl ligand. In this line, the terminal alkyne methyl propiolate gave a mixture of a similar iridacyclophosphapentanone complex and [Ir(ABPN2){CH═C(CO2Me)-CO}{PPh2-CH═CH(CO2Me)}] (10), which bears the functionalized phosphane PPh2-CH═CH(CO2Me) and an iridacyclobutenone fragment. Related model reactions aimed to confirm mechanistic proposals are also studied.

[Cost-utility analysis of triple therapy with telaprevir in treatment-naïve hepatitis C patients]

INTRODUCTION

The prevalence of Hepatitis C (HCV) in Spain is 2,5%, with a high morbimortality rate. Triple therapy based on telaprevir plus peginterferon/ribavirin ([T/PR]) has demonstrated to be an effective approach in treatment-naïve G1-HCV patients. This analysis evaluated, through a Markov model, the incremental cost-effectiveness ratio of triple therapy compared to peginterferon/ ribavirin ([PR]) alone in naïve patients depending on fibrosis stage, from the Spanish Healthcare Authorities perspective.

METHODS

Efficacy results and adverse events incidence were based on the combined results of ADVANCE and OPTIMIZE studies. Adverse events and disease-related costs (€, 2014) were built up from panel expert opinion except from transplant and post-transplant costs, taken from published data. Drug costs were obtained from national databases and adjusted for the mandatory deduction. Outcomes and costs were both discounted at 3%/year.

RESULTS

The analysis shows higher costs and improved outcomes associated with [TR/PR] relative to [PR] alone, resulting in an incremental cost-effectiveness ratio (ICER) of €18,288/ QALY for all the cohort, €14,152QALY for moderate fibrosis, €11,364QALY for bridging fibrosis, €15,929/QALY for cirrhosis. Over a lifetime period, the use of [T/PR] could avoid 12 cirrhosis and 4 liver transplants per 1,000 patients compared to [PR] alone. The probabilistic analysis, following 10,000 Montecarlo simulations, demonstrated the probability of an ICER below a €30,000/QALY gained threshold of 69%. At a willingness- to-pay of €30,000/QALY, [T/PR] could be considered as an efficient option compared with [PR] alone for treatment-naïve genotype 1 HCV patients, over a lifetime horizon.

[Cost analysis of the use of botulinum toxin type A in Spain]

OBJECTIVE

To estimate treatment costs of blepharospasm, cervical dystonia(CD), upper limb spasticity (ULS) and spasticity in children with cerebral palsy (SCCP) with botulinum neurotoxin type A (BoNT-A) in Spain.

METHOD

Annual BoNT-A treatment costs were calculated (2013 ex-factory price () applying RDL 8/2010 and RDL 9/2011 deductions), based on initial dose (id), average dose (ad) and maximum dose (md) according to Summary of Product Characteristics of Botox® (100U/50U), Dysport®(500U) and Xeomin® (100U) and considering the use of complete vials.In addition, annual treatment costs were calculated considering the useof vials in more than one patient and also patient population annual treatment costs based on diseases' prevalence.

RESULTS

Annual BoNT-A treatment costs per patient were estimated at between 265 and 2,120 with savings from 10% to 55% accordingto the selected BoNT-A. CD and ULS treatment provided the greatest cost per patient. Botox® provided greater savings in ULS (id/ad), CD(id), and in blepharospasm and SCCP (id/ad/md). Dysport® treatment was less costly in CD (md) and ULS (md), while Xeomin® was in CD(ad). Based on the estimated treated population in Spain, the annual treatment costs ranged from 368,392 to 13,958,836 depending on indication, dose and BoNT-A considered.

CONCLUSIONS

The appropriate BoNT-A choice would lead to considerable savings for the National Health System. Botox® would generate lower costs per patient than other BoNT-A products in 9 out of 12 scenarios considered.

Rhodium and iridium complexes with a new scorpionate phosphane ligand

A straightforward synthesis of a new hybrid scorpionate ligand [(allyl)2B(CH2PPh2)(Pz)](-) ([A2BPN](-)) is reported. Coordination to rhodium resulted in square-planar complexes [Rh(κ(2)-A2BPN)(L)(L')] [L = L' = (1)/2cod (1,5-cyclooctadiene), CN(t)Bu, CO (6); L = CO, L' = NH3, pyridine, PPh3, PMe3] for which spectroscopic data and the molecular structure of [Rh(κ(2)-A2BPN)(CO)PPh3] (11) indicate the ligand to be κN,κP-bound to rhodium with two dangling free allyl groups. Studies in solution point out that the six-membered Rh-N-N-B-C- P metallacycle undergoes a fast inversion in all of them. The bis(carbonyl) complex 6 easily loses a CO group to give [{Rh(A2BPN)(CO)}2], a dinuclear compound in which two mononuclear subunits are brought together by two bridging allyl groups. Coordination to iridium is dominated by a tripodal κN,κP,η(2)-C═C binding mode in the TBPY-5 complexes [Ir(κ(3)-A2BPN)(L)(L')] [L = L' = (1)/2cod (3), CN(t)Bu (5), CO (7); L = CO, L' = PPh3 (13), PMe3 (14), H2C═CH2, (17), MeO2CC≡CCO2Me (dmad, 18)], as confirmed by the single-crystal structure determination of complexes 3 and 18. A fast exchange between the two allyl arms is observed for complexes having L = L' (3, 5, and 7), while those having CO and L ligands (14, 17, and 18) were found to be nonfluxional species. An exception is complex 13, which establishes an equilibrium with the SP-4 configuration. Protonation reactions on complexes 13 and 14 with HCl yielded the hydride complex [Ir(κ(2)-A2BPN)(CO)(Cl)(H)PPh3] (15) and the C-alkyl compound [ Ir{κ(3)-(allyl)B(CH2 CHCH3)(CH2PPh2)(Pz)}(Cl)(CO)PMe3] (16), respectively. The bis(isocyanide) complex 5 reacts with dmad to form [Ir(κ(2)-A2BPN)(CN(t)Bu)2(dmad)]. On the whole, the electronic density provided to the metal by the [A2BPN](-) ligand is very sensitive to the coordination mode. The basicity of the new ligand is similar to that of the Tp(Me2) ligand in the κN,κP mode but comparable to Tp if coordinated in the κN,κP,η(2)-C═C mode.

Cost analysis of glatiramer acetate vs. fingolimod for the treatment of patients with relapsing-remitting multiple sclerosis in Spain

BACKGROUND

Fingolimod is an innovative drug with a significant budget impact in the treatment of MS in Spain. The aim of this study was to calculate the direct cost comparison of glatiramer acetate and fingolimod for the treatment of patients with relapsing-remitting multiple sclerosis (RRMS) in Spain.

METHODS

A cost analysis model was developed to compare glatiramer acetate and fingolimod, based on a 1-year time horizon. In addition to the pharmacological costs, resource use was estimated for glatiramer acetate (1 hour of training with nursing staff in self-injection techniques for subcutaneous administration) and fingolimod (vaccination for varicella-zoster virus in 5% of patients, 3 complete blood counts per year, 3 ophthalmology visits for prevention of macular edema, 3 transaminase tests to monitor liver function, and cardiovascular monitoring consisting of 1 ECG before the first fingolimod dose and at 6 hours; 1 day outpatients-hospital visit for cardiological monitoring during 6 hours on the day of the first fingolimod dose, with follow-up of blood pressure and heart rate every hour). The pharmacological costs were calculated based on the ex-factory price of the drugs evaluated, using the doses recommended in the respective Summary of Products Characteristics (SmPC). Total invoicing volume was discounted by 7.5%, as laid down in Spanish Royal Decree 8/2010. Unit costs were obtained from the e-Salud database and the drug catalog. Costs in the model are expressed in €2012.

RESULTS

The cost of annual treatment was €9,439.42 for glatiramer acetate and €19,602.18 for fingolimod, yielding a cost difference of €10,162.76. Assuming a fixed budget of €100,000.00, approximately 10 patients could be treated with glatiramer acetate, compared to 5 with fingolimod.

CONCLUSIONS

Fingolimod therapy requires twice the investment as glatiramer acetate.

Cost effectiveness of first-line oral antiviral therapies for chronic hepatitis B : a systematic review

BACKGROUND

Chronic hepatitis B is a common, progressive disease, particularly when viral replication is detected. Oral antivirals can suppress viral replication and prevent or delay the development of cirrhosis and liver-related complications.

OBJECTIVE

The aim of this study was to systematically review the quality of cost-effectiveness evidence on first-line treatment with entecavir (ETV) or tenofovir difumarate (TDF) for patients with chronic hepatitis B.

METHODS

We searched electronic databases and retrieved articles published up to October 2011, in which the cost effectiveness of ETV or TDF was compared with that of other oral antivirals. The quality of the studies identified was assessed with a standard checklist for critical appraisal.

RESULTS

We selected 16 original papers, all published in the last 5 years. There was a conflict of interest in 12 of the 16 studies due to sponsorship by the corresponding pharmaceutical companies. According to the validity assessment, ten studies were classified as high quality. Five studies performed a cost-effectiveness analysis comparing ETV with TDF; they concluded that TDF dominates ETV. The other 11 studies compared ETV or TDF with other strategies; all concluded that ETV and TDF are both cost-effective interventions.

CONCLUSIONS

This systematic review shows that there is valid evidence suggesting that ETV and TDF are cost-effective interventions for the treatment of patients with chronic hepatitis B in many health systems. In countries where both alternatives are available, it appears that TDF dominates ETV. These results could help decision makers and clinicians to understand economic issues regarding the available drugs for first-line treatment of hepatitis B.

Cost effectiveness of prostacyclins in pulmonary arterial hypertension

BACKGROUND

Pulmonary arterial hypertension (PAH) is considered an orphan disease. Prostacyclins are the keystone for PAH treatment. Choosing between the three available prostacyclin therapies could be complicated because there are no comparison studies, so the final decision must be driven by factors such as efficacy, administration route, safety profile and economic aspects.

OBJECTIVE

This study provides a cost-effectiveness and cost-utility comparison of initiating prostacyclin therapy with three different treatment alternatives (inhaled iloprost [ILO], intravenous epoprostenol [EPO] and subcutaneous treprostinil [TRE]) for patients with PAH. The goal of this work is to help physicians with their therapeutic decision-making.

METHODS

A Markov model was built to simulate a patient cohort with class III PAH according to the classification of the New York Heart Association (NYHA). Four health states corresponding with the NYHA classes plus death were allowed for patients in the model. Changing the treatment was possible when patients worsened from functional class III to IV. The time horizon was 3 years, allowing patients to transition between health states on a 12-week cycle basis. The study perspective was that of the National Health System (NHS) [only direct medical costs were included]. Unitary costs were obtained from the Drug Catalogue and e-Salud Database in 2009 and are given in euros (€). Data on health resources and treatment pathways were informed by a four-member expert panel. Efficacy was obtained from pivotal clinical trials of ILO, EPO and TRE, the latter used in Spain as a foreign medication. Utilities for each health state were obtained from the literature. The final efficacy measure was life-years gained (LYG), and utilities were used to obtain quality-adjusted life-years (QALYs). Costs and effects were discounted at a 3% rate. To check for the robustness of the results, sensitivity analyses were performed.

RESULTS

At the end of the 3 years, in the base case of the deterministic analysis, initiating prostacyclin therapy with iloprost was the less costly strategy (€132,840), followed by treprostinil (€359,869) and epoprostenol (€429,775). Epoprostenol has shown the best efficacy results with 2.73 LYG and 1.78 QALY, followed by iloprost (2.69 LYG and 1.74 QALY) and treprostinil (2.69 LYG and 1.73 QALY). Incremental cost-effectiveness ratios (ICER) and cost-utility ratios (ICUR) of epoprostenol versus iloprost and treprostinil were much above the €30,000 per LYG or QALY threshold commonly used in Spain. Iloprost was dominant compared with treprostinil. In the probabilistic analysis, epoprostenol, when compared with iloprost, was a dominant strategy in 15% of the simulations, but it was not a cost-effective option in 83% of the cases. When compared with treprostinil, epoprostenol was dominant in 43% of the simulations. Iloprost was dominant compared with treprostinil in 45% of the cases and it was a cost-effective alternative in 39% of the simulations.

CONCLUSIONS

Initiating prostacyclin treatment with iloprost in patients with PAH, functional class III of the NYHA, is the less costly alternative for the NHS in Spain, with a good efficacy profile when compared with the other alternatives.

Cost-effectiveness analysis of antipsychotics in reducing schizophrenia relapses

BACKGROUND

Schizophrenia is a severe form of mental illness which is associated with significant and long-lasting health, social and financial burdens.The aim of this project is to assess the efficiency of the antipsychotics used in Spain in reducing schizophrenia relapses under the Spanish Health System perspective.

MATERIAL AND METHODS

A decision-analytic model was developed to explore the relative cost-effectiveness of five antipsychotic medications, amisulpride, aripiprazole, olanzapine, paliperidone Extended-Release (ER) and risperidone, compared to haloperidol, over a 1-year treatment period among people living in Spain with schizophrenia. The transition probabilities for assessed therapies were obtained from the systemic review and meta-analysis performed by National Institute for Health and Clinical Excellence (NICE).

RESULTS

Paliperidone ER was the option that yielded more quality-adjusted life years (QALYs) gained per patient (0.7573). In addition, paliperidone ER was the least costly strategy (€3,062), followed by risperidone (€3,194), haloperidol (€3,322), olanzapine (€3,893), amisulpride (€4,247) and aripiprazole (€4,712).In the incremental cost-effectiveness (ICE) analysis of the assessed antipsychotics compared to haloperidol, paliperidone ER and risperidone were dominant options. ICE ratios for other medications were €23,621/QALY gained, €91,584/QALY gained and €94,558/QALY gained for olanzapine, amisulpride and aripiprazole, respectively. Deterministic sensitivity analysis showed that risperidone is always dominant when compared to haloperidol. Paliperidone ER is also dominant apart from the exception of the scenario with a 20% decrease in the probability of relapses.

CONCLUSIONS

Our findings may be of interest to clinicians and others interested in outcomes and cost of mental health services among patients with schizophrenia.Paliperidone ER and risperidone were shown to be dominant therapies compared to haloperidol in Spain. It is worthwhile to highlight that schizophrenia is a highly incapacitating disease and choosing the most appropriate drug and formulation for a particular patient is crucial.The availability of more accurate local epidemiological data on schizophrenia would allow a better adaptation of the model avoiding some of the assumptions taken in our work. Future research could be focused on this.

Di-μ-methanolato-bis[(η4-tetrafluorobenzobarrelene)rhodium(I)]

The versatile synthetic precursor methanolate-bridged title rhodium complex, [Rh(2)(CH(3)O)(2)(C(12)H(6)F(4))(2)] or [Rh(μ-OCH(3))(tfbb)](2) [tfbb = tetrafluorobenzobarrelene or 3,4,5,6-tetrafluorotricyclo[6.2.2.0(2,7)]dodeca-2(7),3,5,9,11-pentaene], has been structurally characterized. The asymmetric unit contains half a molecule that can be expanded via a twofold axis. The title compound has been shown to be a dinuclear rhodium complex where each metal centre is coordinated by two O atoms from two bridging methanolate groups and by the olefinic bonds of a tfbb ligand. Comparison of the bite angles of tfbb, norbornadiene (nbd) and cyclooctadiene (cod) olefins in their η(4)-coordination to rhodium reveals similarities between the tfbb and nbd ligands, which are much more rigid than cod. The short distance found between the distorted square-planar metal centres [2.8351 (4) Å] has been related to the syn conformation of the folded core `RhORhO' ring.

Cost-effectiveness of posaconazole versus fluconazole or itraconazole in the prevention of invasive fungal infections among high-risk neutropenic patients in Spain

BACKGROUND

We evaluated the cost-effectiveness of posaconazole compared with standard azole therapy (SAT; fluconazole or itraconazole) for the prevention of invasive fungal infections (IFI) and the reduction of overall mortality in high-risk neutropenic patients with acute myelogenous leukaemia (AML) or myelodysplastic syndromes (MDS). The perspective was that of the Spanish National Health Service (NHS).

METHODS

A decision-analytic model, based on a randomised phase III trial, was used to predict IFI avoided, life-years saved (LYS), total costs, and incremental cost-effectiveness ratio (ICER; incremental cost per LYS) over patients' lifetime horizon. Data for the analyses included life expectancy, procedures, and costs associated with IFI and the drugs (in euros at November 2009 values) which were obtained from the published literature and opinions of an expert committee. A probabilistic sensitivity analysis (PAS) was performed.

RESULTS

Posaconazole was associated with fewer IFI (0.05 versus 0.11), increased LYS (2.52 versus 2.43), and significantly lower costs excluding costs of the underlying condition (€6,121 versus €7,928) per patient relative to SAT. There is an 85% probability that posaconazole is a cost-saving strategy compared to SAT and a 97% probability that the ICER for posaconazole relative to SAT is below the cost per LYS threshold of €30,000 currently accepted in Spain.

CONCLUSIONS

Posaconazole is a cost-saving prophylactic strategy (lower costs and greater efficacy) compared with fluconazole or itraconazole in high-risk neutropenic patients.

Budgetary impact analysis of buprenorphine-naloxone combination (Suboxone®) in Spain

BACKGROUND

Opioid addiction is a worldwide problem. Agonist opioid treatment (AOT) is the most widespread and frequent pharmacotherapeutic approach. Methadone has been the most widely used AOT, but buprenorphine, a partial μ-opiod agonist and a κ-opiod antagonist, is fast gaining acceptance. The objective was to assess the budgetary impact in Spain of the introduction of buprenorphine-naloxone (B/N) combination.

METHODS

A budgetary impact model was developed to estimate healthcare costs of the addition of B/N combination to the therapeutic arsenal for treating opioid dependent patients, during a 3-year period under the National Health System perspective. Inputs for the model were obtained from the specialized scientific literature. Detailed information concerning resource consumption (drug cost, logistics, dispensing, medical, psychiatry and pharmacy supervision, counselling and laboratory test) was obtained from a local expert panel. Costs are expressed in euros (€, 2010).

RESULTS

The number of patients estimated to be prescribed B/N combination was 2,334; 2,993 and 3,589 in the first, second and third year respectively. Total budget is €85,766,129; €79,855,471 and €79,137,502 in the first, second and third year for the scenario without B/N combination. With B/N combination the total budget would be €86,589,210; €80,398,259 and €79,708,964 in the first, second and third year of the analyses. Incremental cost/patient comparing the addition of the B/N combination to the scenario only with methadone is €10.58; €6.98 and €7.34 in the first, second and third year respectively.

CONCLUSION

Addition of B/N combination would imply a maximum incremental yearly cost of €10.58 per patient compared to scenario only with methadone and would provide additional benefits.

[Cost analysis of 3 candins in the treatment of invasive candidiasis in adult non-neutropaenic patients in Spain]

OBJECTIVE

To estimate the cost of 3 candins (anidulafungin, caspofungin and micafungin) in the treatment of adult non-neutropaenic patients with invasive candidiasis (IC) in a Spanish hospital pharmacy setting.

METHODS

The overall cost impact was evaluated by varying the percentage dosage required of each candin in different possible scenarios. The prices (in euros) for each presentation were obtained from the Drug Catalogue (in August 2010). Only drug purchase costs were considered. The results are expressed as total cost for each of the 3 candins.

RESULTS

The cost per episode (14 days) of anidulafungin was constant at €5400 per patient. The cost of caspofungin varied from €4281 to €7991, depending on patient weight and liver dysfunction. The cost of micafungin varied from €6000 (100mg/day) to €9000 (when increasing the dose due to inadequate response). Based on a hypothetic cohort of 100 patients with IC, the total cost of anidulafungin treatment would be €540,000, for caspofungin it would be €631,459, and for micafungin it would be €632,998, depending on any dose adjustment required.

CONCLUSION

Patients treated with anidulafungin did not require dose adjustment, unlike those treated with caspofungin or micafungin. The use of anidulafungin is a cost-saving treatment for adult non-neutropaenic patients with IC, which would result in better control of the Spanish pharmacy budget.

Efficacy of taxanes as adjuvant treatment of breast cancer: a review and meta-analysis of randomised clinical trials

OBJECTIVES

To evaluate the magnitude of benefit obtained by taxanes as adjuvant treatment of breast cancer and to assess the best method for their administration.

MATERIAL AND METHODS

We performed a systematic search of phase III randomised clinical trials that included patients with non-metastatic breast cancer in whom comparisons were chemotherapy (CT) containing a taxane (docetaxel or paclitaxel) vs. CT without taxanes (first-generation trials), or CT with taxane in both treatment arms (second-generation trials), administered after surgery. The parameters of efficacy evaluated were disease-free survival (DFS) and overall survival (OS). The data obtained in the first-generation trials (number of relapses and deaths) were submitted to a meta-analysis. The odds ratio (OR) combined with DerSimonian and Laird (OR DL) and 95% confidence interval (95% CI) were calculated. Further, an analysis was performed of those trials that included only patients with nodal involvement (N+). In both cases, the results were also analysed as a function of the taxane used, and with indirect comparisons between the two. The second-generation trials were analysed to assess the optimum method of administration.

RESULTS

A total of 17 trials were selected for the meta-analysis (30,672 patients). The OR DL was 0.82 (95%CI: 0.76-0.88) for DFS and 0.83 (95% CI: 0.75-0.91) for OS. In N+ patients the results were 0.80 (95% CI: 0.74-0.86) and 0.79 (95% CI: 0.69-0.89), respectively. Docetaxel and paclitaxel significantly increased the DFS and OS. In our indirect comparison, the benefit of docetaxel on OS was significantly superior to that obtained with paclitaxel in N+ patients (OR: 0.79; 95% CI: 0.63-0.98).

CONCLUSIONS

The administration of adjuvant CT-based taxanes reduces the risk of relapse and death. This reduction is superior in clinical trials that included only N+ patients. With the available evidence, it would appear that the best method of administering paclitaxel is weekly and for docetaxel tri-weekly.