Recent trends in brand-name and generic drug competition

Objective:

To provide evidence on recent trends in: (1) market exclusivity periods (MEPs, the time between launch of a brand-name drug and its first generic competitor) for new molecular entities (NMEs); (2) the likelihood and timing of patent challenges under Paragraph IV of the Hatch-Waxman Act; and (3) generic drug penetration.

Methods:

IMS Health National Sales Perspectives data were used to calculate MEPs for the 257 NMEs experiencing initial generic entry between January 1995 and September 2012 and the number of generic competitors for 12 months afterwards, by level of annual sales prior to generic entry and time period. The likelihood and timing of Paragraph IV challenge were calculated using data from Abbreviated New Drug Approval (ANDA) approval letters, the FDA website, and public information searches to identify drugs experiencing Paragraph IV filings, and the first filing date.

Results:

For drugs experiencing initial generic entry in 2011–2012, the MEP was 12.6 years for drugs with sales greater than $100 million (in 2008 dollars) in the year prior to generic entry, 12.9 years overall. After generic entry, the brand rapidly lost sales, with average brand unit share of 16% at 1 year; 11% for NMEs with pre-generic entry sales of at least $250 million (in 2008 dollars). Over 80% of NMEs experiencing 2011–2012 initial generic entry had faced at least one Paragraph IV challenge from a generic manufacturer. These challenges were filed relatively early in the brand-name drug life cycle: within 7 years after brand launch, on average.

Limitations:

Analyses, including Paragraph IV calculations, were restricted to NMEs where generic entry had occurred.

Conclusion:

Pharmaceutical competition continues to evolve; while the average MEP below 13 years for 2011–2012 remains consistent with prior research, Paragraph IV challenges are increasingly frequent and occur earlier, and generic share erosion has intensified.     

The Rise,Fall and Rebirth of Polish Political Geography

The article presents an outline of the history of Polish political geography. Its development as a science in fact began in the nineteenth century and its golden age lasted all the way through to the fall of the Polish state in 1939. The loss of independence in the period 1939/1945–1989 also brought with it the fall of political geography in Poland. After 1989, along with the restoration of freedom of research in Poland, a new period started in the history of Polish political geography.     

Economic development and the role of agricultural technology

In earlier debates on economic development, the agricultural sector's role was somewhat controversial. While dualistic models highlighted the importance of agriculture, the mainstream literature placed a greater emphasis on the creation of a modern industrial sector. Soon agriculture disappeared from the mainstream development literature to re‐emerge recently with a variety of multiple‐sector growth models emphasizing the key role of agriculture and specifically technology in agriculture. This article is an empirical cross‐country analysis of agricultural technology's role in economic development. Specifically, the hypothesis being tested is whether improvements in agricultural technology have a significant impact on long‐run economic growth. The results indicate that agricultural modernization has a positive effect on both measures of economic growth and human development.     

Political Development,Agriculture, and Ethnic Divisions: An African Perspective

Abstract: In this paper it is argued that political development is the key to long‐run growth in developing nations. Political development is seen to be dependent on the extent to which a state or ruling elite's income is earned or unearned. The availability of earned income is linked to the structure and productivity of the agricultural sector. Applying the analysis to the sub‐Saharan African experience involves taking into account three factors: the international environment, the ethnic division of societies as a result of colonization, and the urban bias which characterized the economic strategy of the newly independent African states. As a result, agriculture collapsed, the ruling elite became increasingly dependent on unearned income, political underdevelopment occurred. The collapse of state authority significantly impoverished the region and resulted in significant civil conflict. Any long‐run solution must incorporate a broad‐based expansion in agricultural productivity.     

Estimation of demand and supply functions from univariate sample with known separation

It is shown that the joint unconditional density function of demand and supply is a computable function of parameters of the conditional density function of the observed quantity. Propositions of formulating unconditional and conditional disequilibrium measures are suggested.     

The examination of pecan price differences using spatial correlation estimation

A spatial analysis is used to model factors that explain the price received by pecan growers. Besides the statistical aspect of the study focussing on spatial autoregressive residuals, the economic analysis of the paper identifies linkages between the price for in-shell pecans received by growers and the characteristics of the orchard, production costs and resources, and the orchard location.     

The impact of license regulation on the number of recreation trips: is it worth considering?

A two-stage nonlinear least-squares model (2NLS) with an endogenous treatment effect on recreation trips describes the behavior of recreationists with and without a fishing/hunting license. The proposed 2NLS is applied to the derivation of the policy-relevant average gains in the presence of an endogeneity bias to a license fee implementation program regulated by states. Recreationists who purchased a license are likely to recreate more than are the nonlicensed holders because the regulation may reduce congestions at sites where licensee visit often. The license regulation has a greater impact on the use of natural resources after controlling observed and unobserved confounders which might be correlated with the probability of being a license holder and with the final outcome, the number of recreation trips. We confirm that the individual without a permit regards the recreation trip as less valuable than does the individual having a license permit. We also found that the likelihood of purchasing a license among young adult recreationists is not at the level the states may desire. In addition, the number of trips demanded is more responsive to the nontransportation-related implicit travel cost than to the transportation-related implicit travel cost, although travel implicit costs are price inelastic.      

A small forward-looking inter-country model (Belarus, Russia and Ukraine)

The paper describes an inter-country model developed on the New Keynesian Phillips curve principle for the economies of Belarus, Russia and Ukraine. Technically the modelling idea has been grounded within the concept of the infinite dimensional vector autoregressive models by Chudik and Pesaran [Chudik A., Pesara M.H., 2007. Infinite-dimensional VAR's and factor models. IZA; DP No. 3206]. The main developments are such that the model is 1) interdependent rather than vector autoregressive, 2) estimated by the generalised method of moments and 3) forward-looking. The primary linkage of the country models is provided through the real effective exchange rates of particular countries, while the secondary linkages are through the Chudik and Pesaran cross-sectional augmentations. A series of Monte Carlo experiments confirms that the small cross-dimension of the model and a possible dominance of one country in the panel (Russia) should not distort the results in a significant way. A series of stochastic simulation experiments made with and without the assumption of observational equivalence principle shows a possible spread of the Dutch Disease from Russia to other countries in the model.     

TECHNOLOGICAL CHANGE AND SURPLUS LABOUR IN EGYPTIAN AGRICULTURE, 1952–1972

This paper has two main purposes. First to determine if technical innovation has occurred in Egyptian agriculture and whether or not it has been labour-using in nature. Secondly, to determine whether or not the marginal product of labour in Egyptian agriculture has been negative (surplus labour). The time period covered by the study is 1952 to 1972. The above objectives were met by estimating a weak disposability of inputs (WDI) production function. The characteristics of the weak disposability of inputs function were discussed in great detail, since much of the profession is unfamiliar with this functional form. The function was then estimated and the results seemed to indicate that this functional form was appropriate for Egyptian agriculture. The results of the estimation process indicated that labour-using technical innovation had indeed occurred, although at a very slow rate. In addition, for most of the time period covered the marginal product of labour was indeed negative.