Evolution of the sheep coat: the impact of domestication on its structure and development.

Wild sheep and many primitive domesticated breeds have two coats: coarse hairs covering shorter, finer fibres. Both are shed annually. Exploitation of wool for apparel in the Bronze Age encouraged breeding for denser fleeces and continuously growing white fibres. The Merino is regarded as the culmination of this process. Archaeological discoveries, ancient images and parchment records portray this as an evolutionary progression, spanning millennia. However, examination of the fleeces from feral, two-coated and woolled sheep has revealed a ready facility of the follicle population to change from shedding to continuous growth and to revert from domesticated to primitive states. Modifications to coat structure, colour and composition have occurred in timeframes and to sheep population sizes that exclude the likelihood of variations arising from mutations and natural selection. The features are characteristic of the domestication phenotype: an assemblage of developmental, physiological, skeletal and hormonal modifications common to a wide variety of species under human control. The phenotypic similarities appeared to result from an accumulation of cryptic genetic changes early during vertebrate evolution. Because they did not affect fitness in the wild, the mutations were protected from adverse selection, becoming apparent only after exposure to a domestic environment. The neural crest, a transient embryonic cell population unique to vertebrates, has been implicated in the manifestations of the domesticated phenotype. This hypothesis is discussed with reference to the development of the wool follicle population and the particular roles of Notch pathway genes, culminating in the specific cell interactions that typify follicle initiation.

Pulmonary and cardiovascular safety of inhaled insulin in routine practice: The Exubera Large Simple Trial (VOLUME).

OBJECTIVE: VOLUME is a randomized, open-label, post-approval pragmatic trial aiming to evaluate long-term pulmonary and cardiovascular safety of Exubera® (EXU; insulin human [rDNA origin] Inhalation Powder) in routine clinical practice. The primary study objective is to compare risk of persistent decline in forced expiratory volume in 1 second (FEV1) among patients treated with and without EXU. RESEARCH DESIGN AND METHODS: Patients eligible to take EXU per approved local label were randomized to EXU or routine care and followed per usual care, with scheduled FEV1 tests at baseline, 6 months, and yearly.Randomization halted in October 2007 after Pfizer announced it would stop marketing EXU due to low sales. EXU patients were subsequently transitioned to usual care and all patients were followed for 6 additional months. RESULTS: Although there was insufficient power to evaluate the primary endpoint (37% of the planned 5,300 were randomized), the study provided important descriptive information.Per the primary endpoint definition, more EXU group patients (n = 8) experienced a persistent decline in FEV1 (n = 0 in usual care). Using a broader, clinically relevant pre-specified supplementary definition of persistent decline, similar numbers were observed in the EXU (n = 27) and usual care (n = 24) groups. Slightly more pulmonary and allergic serious adverse event composite endpoints were seen in the EXU group. There were no consistent treatment group differences in the cardiovascular composite endpoint, all-cause mortality, or glycemic control. CONCLUSIONS: Clinically important declines in lung function that persisted more than 60 days were uncommon and of similar frequency in Exubera and usual care. CLINICALTRIALSGOV: NCT00359801.

Implications of product withdrawal on a post-approval pragmatic trial: The VOLUME study experience.

INTRODUCTION: Many clinical trials terminate early due to safety and efficacy concerns, and less often due to unexpected "positive" findings. However, early termination of post-approval (Phase IV) pragmatic randomized trials for commercial reasons is less frequent, may be more complex, and may require added flexibility in closure methods, including short term follow-up. VOLUME was a randomized, open-label, post-approval pragmatic clinical trial (PCT) or large simple trial that terminated early due to product withdrawal. The aim of this paper is to describe circumstances unique to post-approval PCTs that may require a closure amendment rather than immediate study termination, and our recommendations for operational study closure in these circumstances. We use the VOLUME case study throughout to provide a practical example. METHODS: Study closeout considerations at the study level include: notifying external governance bodies, e.g., data monitoring committees (DMC), and scientific steering committees (SSC); executing a study closure amendment; notifying and training of study physicians; and institutional review board (IRB)/ethics committee (EC) approvals. Study closure considerations at the patient level focus on patient safety and include: patient notification, efficient transition to alternative treatments, the need for re-consenting; and drug supply shortages. CONCLUSIONS: Early study closeout logistics require careful analysis, detailed planning, and close coordination, and are ideally considered at the study planning phase. Lessons learned from the VOLUME closeout should help other researchers devise contingencies when terminating post approval pragmatic trials that utilize a marketed product.ClinicalTrials.gov: NCT00359801.

Lung Cancer-Related Mortality With Inhaled Insulin or a Comparator: Follow-Up Study of patients previously enrolled in Exubera Controlled Clinical Trials (FUSE) Final Results.

OBJECTIVE: The Follow-Up Study of patients previously enrolled in Exubera controlled clinical trials (FUSE) was designed to evaluate whether patients previously treated with Exubera (EXU; insulin human [rDNA origin], inhaled powder) in controlled clinical trials died because of incident primary lung cancer at a substantially higher rate than patients treated with a comparator. RESEARCH DESIGN AND METHODS: FUSE is a hybrid, randomized, controlled trial/cohort study including participants of 17 prior EXU clinical trials. Pooled patient data from these trials were used, and the subset of patients enrolled in the follow-up cohort study was followed prospectively for 2 years in order to evaluate the incidence of fatal and nonfatal primary lung cancers and all-cause mortality. RESULTS: There were 24,409 person-years (PY) of observation among 7,439 trial patients, with 4,017 PY (16.5%) from the period after the trials but before the prospective follow-up and 5,299 PY (21.7%) from the prospective follow-up. Just over half of the 2,631 patients (51.6%) in the prospective follow-up were randomized to EXU in the original trial. The incidence density ratio was 2.8 (95% CI 0.5, 28.5) for lung cancer-related mortality and 3.7 (95% CI 1.0, 20.7) for incident primary lung cancer. The hazard ratio for all-cause mortality was 0.81 (95% CI 0.60, 1.10). CONCLUSIONS: These data cannot exclude an increased risk of lung cancer-related mortality associated with EXU use. If real, the absolute increased risk of lung cancer-related mortality was small (0.48 cases per 1,000 PY). For all-cause mortality-the most reliably measured end point with the clearest interpretation-EXU users did not experience an excess all-cause death rate (relative or absolute) compared with users of other diabetes treatments over the study period.

Report of the European Society of Cardiology Cardiovascular Round Table regulatory workshop update of the evaluation of new agents for the treatment of acute coronary syndrome: Executive summary.

Regulatory authorities interpret the results of randomized controlled trials according to published principles. The European Medicines Agency (EMA) is planning a revision of the 2000 and 2003 guidance documents on clinical investigation of new medicinal products for the treatment of acute coronary syndrome (ACS) to achieve consistency with current knowledge in the field. This manuscript summarizes the key output from a collaborative workshop, organized by the Cardiovascular Round Table and the European Affairs Committee of the European Society of Cardiology, involving clinicians, academic researchers, trialists, European and US regulators, and pharmaceutical industry researchers. Specific questions in four key areas were selected as priorities for changes in regulatory guidance: patient selection, endpoints, methodologic issues and issues related to the research for novel agents. Patients with ST-segment elevation myocardial infarction (STEMI) and non-STEMI (NSTEMI) should be studied separately for therapies aimed at the specific pathophysiology of either condition, particularly for treatment of the acute phase, but can be studied together for other treatments, especially long-term therapy. Unstable angina patients should be excluded from acute phase ACS trials. In general, cardiovascular death and reinfarction are recommended for primary efficacy endpoints; other endpoints may be considered if specifically relevant for the therapy under study. New agents or interventions should be tested against a background of evidence-based therapy with expanded follow-up for safety assessment. In conclusion, new guidance documents for randomized controlled trials in ACS should consider changes regarding patient and endpoint selection and definitions, and trial designs. Specific requirements for the evaluation of novel pharmacological therapies need further clarification.

Improving clinical trials for cardiovascular diseases: a position paper from the Cardiovascular Round Table of the European Society of Cardiology.

AIMS: Cardiovascular disease is the most common cause of mortality and morbidity in the world, but the pharmaceutical industry's willingness to invest in this field has declined because of the many challenges involved with bringing new cardiovascular drugs to market, including late-stage failures, escalating regulatory requirements, bureaucracy of the clinical trial business enterprise, and limited patient access after approval. This contrasts with the remaining burden of cardiovascular disease in Europe and in the world. Thus, clinical cardiovascular research needs to adapt to address the impact of these challenges in order to ensure development of new cardiovascular medicines. METHODS AND RESULTS: The present paper is the outcome of a two-day workshop held by the Cardiovascular Round Table of the European Society of Cardiology. We propose strategies to improve development of effective new cardiovascular therapies. These can include (i) the use of biomarkers to describe patients who will benefit from new therapies more precisely, achieving better human target validation; (ii) targeted, mechanism-based approaches to drug development for defined populations; (iii) the use of information technology to simplify data collection and follow-up in clinical trials; (iv) streamlining adverse event collection and reducing monitoring; (v) extended patent protection or limited rapid approval of new agents to motivate investment in early phase development; and (vi) collecting data needed for health technology assessment continuously throughout the drug development process (before and after approval) to minimize delays in patient access. Collaboration across industry, academia, regulators, and payers will be necessary to enact change and to unlock the existing potential for cardiovascular clinical drug development. CONCLUSIONS: A coordinated effort involving academia, regulators, industry, and payors will help to foster better and more effective conduct of clinical cardiovascular trials, supporting earlier availability of innovative therapies and better management of cardiovascular diseases.