Using an economic simulation model to identify key drivers of profitability and estimate the environmental sustainability impact of immunization against gonadotropin-releasing factor (GnRF) in male and female pigs intended for market

An existing model was used to identify key drivers of profitability and estimate the impact on environmental sustainability when immunizing finishing pigs against GnRF with Improvac®. The model estimated performance and economic differences between immunized (IM) and non-IM pigs from the perspective of producers and packers, based on two recent meta-analyses in male and female pigs. It was populated with data from 9 countries in four continents (Europe, Asia, North and Latin-America). One-way sensitivity analyses (OWSA) were used to define key drivers of profitability. When changing the country specific input data over a range of ±20%, most OWSA did not reverse the mathematical sign of incremental net return between IM and non-IM pigs as calculated in base case analyses. Only the difference in feed conversion rate between IM and untreated female pigs was a key driver of profitability. The parameters with the highest impact on outcomes were similar across countries and expectable (feed costs), or explainable (parameters with statistical differences between IM and non-IM pigs in meta-analyses). In both single-gender herds, Improvac® reduced the environmental impact of pig production by improving feed efficiency (FE), the key driver of environmental burden. In a 50/50 mixed gender herd, IM pigs consumed less feed and gained more weight in 7 out of 9 countries; in the other two countries the FE calculated for the additional weight gain in IM pigs was >1.00, i.e., each additional kilogram of weight gain was associated with less than one additional kilogram of feed consumed.

Cost-effectiveness analysis of quadrivalent influenza vaccination in at-risk adults and the elderly: an updated analysis in the U.K

OBJECTIVE

To update an earlier evaluation estimating the cost-effectiveness of quadrivalent influenza vaccination (QIV) compared with trivalent influenza vaccination (TIV) in the adult population currently recommended for influenza vaccination in the UK (all people aged ≥65 years and people aged 18-64 years with clinical risk conditions).

METHODS

This analysis takes into account updated vaccine prices, reference costs, influenza strain circulation, and burden of illness data. A lifetime, multi-cohort, static Markov model was constructed with seven age groups. The model was run in 1-year cycles for a lifetime, i.e., until the youngest patients at entry reached the age of 100 years. The base-case analysis was from the perspective of the UK National Health Service, with a secondary analysis from the societal perspective. Costs and benefits were discounted at 3.5%. Herd effects were not included. Inputs were derived from systematic reviews, peer-reviewed articles, and government publications and databases. One-way and probabilistic sensitivity analyses were performed.

RESULTS

In the base-case, QIV would be expected to avoid 1,413,392 influenza cases, 41,780 hospitalizations, and 19,906 deaths over the lifetime horizon, compared with TIV. The estimated incremental cost-effectiveness ratio (ICER) was £14,645 per quality-adjusted life-year (QALY) gained. From the societal perspective, the estimated ICER was £13,497/QALY. A strategy of vaccinating only people aged ≥65 years had an estimated ICER of £11,998/QALY. Sensitivity analysis indicated that only two parameters, seasonal variation in influenza B matching and influenza A circulation, had a substantial effect on the ICER. QIV would be likely to be cost-effective compared with TIV in 68% of simulations with a willingness-to-pay threshold of <£20,000/QALY and 87% with a willingness-to-pay threshold of <£30,000/QALY.

CONCLUSIONS

In this updated analysis, QIV was estimated to be cost-effective compared with TIV in the U.K.

Estimating the comparative clinical and economic consequences of tulathromycin for treatment of present or anticipated outbreaks of bovine respiratory disease in feedlot cattle in the United States

The goal of this study was to determine the clinical and economic impact of using tulathromycin as first line treatment for bovine respiratory disease (BRD) compared with other commonly used antimicrobials. Two decision trees were developed simulating the consequences of treating cattle at high risk of developing BRD [control model (CM)] or cattle with first clinical BRD episode [treatment model (TM)]. As comparators florfenicol and tilmicosin were considered in both models whereas enrofloxacin was included in the TM because it was only labeled for treatment of BRD at the time of development of the calculators. A total of 5 (CM) and 10 (TM) comparative clinical studies that reported efficacy data for the selected drugs and indications were identified as suitable for model population. The following outcomes were considered: first treatment success, number of subsequent BRD treatments, chronics, and mortalities. Cost parameters were considered from the perspective of the producer and included treatment costs (first treatment and retreatments) and costs of chronics and deaths derived from published sources for 2010 (default). The models allowed the estimation of clinical and economic consequences according to each individual trial outcomes. Treatment with tulathromycin resulted in more first treatment successes and fewer removals (chronics and deaths) in all comparisons. The average total number of antimicrobial treatments required for the management of BRD was also least with tulathromycin as first treatment option. Because of better efficacy, total costs over the entire study periods were always lowest with tulathromycin. Depending on the study selected as the basis for the efficacy evaluation, cost savings with tulathromycin were calculated in the CM between US$21.00 and $47.86 (vs. florfenicol) and $11.37 and $72.64 (vs. tilmicosin); cost savings in the TM ranged between $28.47 and $143.87 (vs. florfenicol) and $7.75 and $84.91 (vs. tilmicosin) as well as between $23.22 and $47.82 (vs. enrofloxacin), with the ranges reflecting a variety of settings in different trials. Thus, the higher drug costs of tulathromycin were more than offset by reduced BRD treatments, chronics, and mortalities in the herd. Fewer BRD episodes in cattle treated with tulathromycin not only contributes to overall savings in BRD management but also reduces the necessity of repeated antibiotic treatment, supporting prudent use of antimicrobials in livestock.

[Pharmacoeconomics in uro-oncology: the concept of QALYs]

The QALY (quality-adjusted life year) is often used in pharmacoeconomic evaluations. It combines the two dimensions 'quality of life' and 'life expectancy' into one index. Quality of life is expressed as a utility, corresponding to a value between 0 (death) and 1 (perfect health). Life expectancy is then multiplied by the utility corresponding to the quality of life of the respective life time. Accordingly, 1 QALY corresponds to 1 year in perfect health (1 year multiplied by utility 1) or 2 years with a quality of life reduced by 50% (2 years multiplied by utility 0.5). Results of pharmacoeconomic evaluations are often reported as additional costs in relation to the added value of a new treatment, expressed as cost per additional QALY gained for the patient with the new therapeutic intervention. The main advantage of the QALY concept is its validity for all patients and indications. And the use of benefit measures which are not restricted to a specific indication is most important for resource allocation, i.e. to avoid that varying amounts of money are paid for the same health benefit in different disease areas.

[Pharmacodynamic and pharmacokinetic aspects of the non-inflammatory non-steroidal agent meloxicam in dogs]

The pharmacodynamics of non-steroidal anti-inflammatory drugs (NSAIDs) are for the most part well-understood. All NSAIDs inhibit the enzyme cyclooxygenase (COX), and for this reason prostaglandin synthesis. Two isoforms of COX could be isolated. COX-1 is detectable in most tissues on a constant level and is responsible for the synthesis of prostaglandins with cytoprotective effects. COX-2 is induced through inflammation and supports the inflammatory process by producing pro-inflammatory prostaglandins. The desired effects of NSAIDs are related to inhibition of COX-2, whereas inhibition of COX-1 has been linked to the typical side-effects of NSAIDs, especially in the stomach and kidney. The great differences between effects and side-effects in the numerous substances can be explained because of different interactions of the NSAIDs on COX-1 and COX-2. In various test systems meloxicam has been shown to be a preferential inhibitor of COX-2. There are also large differences between the individual NSAIDs with regard to pharmacokinetics. Meloxicam is completely absorbed from the gastrointestinal tract and has an elimination half-life of 24 hours in the dog. It is excreted in faeces and urine. The metabolites, detectable in urine are biologically inactive and do not influence the prostaglandin synthesis in the kidney. In the underlying study, plasma concentration of meloxicam was determined after a subcutaneous injection of 0.2 mg/kg b. w. (day 1) followed by oral treatment of 0.1 mg/kg b. w. (days 2-14). The results confirm the recommended dosage regime of meloxicam with its initial loading dose and the subsequent maintenance dose. This dosing regime results in a very favourable curve of concentrations with a very rapidly attained steady state after roughly two days, without accumulation even in long-term treatment.