Instability and network effects in innovative markets

We consider a network of interacting agents and we model the process of choice on the adoption of a given innovative product by means of statistical-mechanics tools. The modelization allows us to focus on the effects of direct interactions among agents in establishing the success or failure of the product itself. Mimicking real systems, the whole population is divided into two sub-communities called, respectively, Innovators and Followers, where the former are assumed to display more influence power. We study in detail and via numerical simulations on a random graph two different scenarios: no-feedback interaction, where innovators are cohesive and not sensitively affected by the remaining population, and feedback interaction, where the influence of followers on innovators is non negligible. The outcomes are markedly different: in the former case, which corresponds to the creation of a niche in the market, Innovators are able to drive and polarize the whole market. In the latter case the behavior of the market cannot be definitely predicted and become unstable. In both cases we highlight the emergence of collective phenomena and we show how the final outcome, in terms of the number of buyers, is affected by the concentration of innovators and by the interaction strengths among agents.Comment: 20 pages, 6 figures. 7th workshop on "Dynamic Models in Economics and Finance" - MDEF2012 (COST Action IS1104), Urbino (2012

L'Italia come modello per l'Europa e per il mondo nelle politiche sanitarie per il trattamento dell'epatite cronica da HCV

The World Health Organization foresees the elimination of HCV infection by 2030. In light of this and the curre nt, nearly worldwide, restriction in direct-acting agents (DAA) accessibility due to their high price, we aimed to evaluate the cost-effectiveness of two alternative DAA treatment policies: Policy 1 (universal): treat all patients, regardless of the fibrosis stage; Policy 2 (prioritized): treat only priori tized patients and delay treatment of the remaining patients until reaching stage F3. T he model was based on patient’s data from the PITER cohort. We demonstrated that extending HC V treatment of patients in any fibrosis stage improves health outcomes and is cost-effective

Economic consequences of investing in anti-HCV antiviral treatment from the Italian NHS perspective : a real-world-based analysis of PITER data

OBJECTIVE: We estimated the cost consequence of Italian National Health System (NHS) investment in direct-acting antiviral (DAA) therapy according to hepatitis C virus (HCV) treatment access policies in Italy. METHODS: A multistate, 20-year time horizon Markov model of HCV liver disease progression was developed. Fibrosis stage, age and genotype distributions were derived from the Italian Platform for the Study of Viral Hepatitis Therapies (PITER) cohort. The treatment efficacy, disease progression probabilities and direct costs in each health state were obtained from the literature. The break-even point in time (BPT) was defined as the period of time required for the cumulative costs saved to recover the Italian NHS investment in DAA treatment. Three different PITER enrolment periods, which covered the full DAA access evolution in Italy, were considered. RESULTS: The disease stages of 2657 patients who consecutively underwent DAA therapy from January 2015 to December 2017 at 30 PITER clinical centres were standardized for 1000 patients. The investment in DAAs was considered to equal €25 million, €15 million, and €9 million in 2015, 2016, and 2017, respectively. For patients treated in 2015, the BPT was not achieved, because of the disease severity of the treated patients and high DAA prices. For 2016 and 2017, the estimated BPTs were 6.6 and 6.2 years, respectively. The total cost savings after 20 years were €50.13 and €55.50 million for 1000 patients treated in 2016 and 2017, respectively. CONCLUSIONS: This study may be a useful tool for public decision makers to understand how HCV clinical and epidemiological profiles influence the economic burden of HCV

A new treatment regimen with permethrin in scabies

BACKGROUND: Topical permethrin, applied once daily, is considered as the most effective treatment in scabies. METHODS: Eighty-nine adult immunocompetent patients with scabies were treated with 5% permethrin cream: 42 patients were treated with a single application/day (group I); 47 patients were treated with one application/day for two consecutive days (group II). Clinical diagnosis of scabies was confirmed by microscopical examinations. The cream was stored in refrigerator and applied cold on the entire skin surface. The cream was left on the skin for 24 hours. No other topical or systemic drugs were allowed, except for a cleanser with chlorhexidine. The treatment was repeated in all patients 7-10 days later. Follow up length was two months after the end of the treatment. RESULTS: Twenty-one patients (61.8%) in the group I and 34 patients (87.2%) in the group II were considered recovered both clinically and microscopically. Three patients (7.1%) in the group I and 4 patients (10.2%) in the group II developed a mild irritant contact dermatitis. During follow-up, three patients (7.1%) in the group I and two patients (4.2%) in the group II developed a recurrence or a re-infestation. CONCLUSIONS: Five per cent permethrin, when applied as cold cream, on the entire skin surface, once daily for two consecutive days, is more effective than the single application in adult immunocompetent patients with scabies

Treatment of pruritus in mild-to-moderate atopic dermatitis with a topical non-steroidal agent

Atopiclair (Zarzenda) is a topical non-steroidal anti-inflammatory agent for the treatment of allergic diseases of the skin. Three main ingredients are contained in this product: glycyrrhetinic acid, telmesteine and Vitis vinifera extracts. Other ingredients include: allantoin, alpha-bisabolol, capryloyl glycine, hyaluronic acid, shea butter and tocopheryl acetate. Two previous randomized, double-blind, vehicle-controlled clinical studies provided evidence that Atopiclair is effective in the treatment of atopic dermatitis. This article presents an open, multicenter, sponsor-free, study on the anti-pruritic activity of this product in adult patients with mild-to-moderate atopic dermatitis. The Median Visual Analogue Scale (VAS) values were: at the start of the study (TO), median VAS was 48.5 mm; three weeks later (T1), median VAS was 34.1 mm (-14.4 mm from baseline); six weeks later (T2), median VAS was 24.6 mm (-23.9 mm from baseline). Statistical analysis revealed that differences between TO versus T1, TO versus T2 and T1 versus T2 were highly significant (p<0.001). Side effects (local burning) were relatively common, although mild in severity. On the basis of the results of this study, Atopiclair showed efficacy in relief of pruritus in adult patients with mild-to-moderate atopic dermatitis