Pricing, Patent Loss and the Market For Pharmaceuticals

Empirical studies suggest that entry of generic competitors results in minimal decreases or even increases in brand-name drug prices as well as sharp declines in brand-name advertising. This paper examines circumstances under which this empirical pattern could be observed. The analysis focuses on models where the demand for brand-name pharmaceuticals is divided into two segments, only one of which is cross-price-sensitive. Brand-name firms are assumed to set price and advertising in a Stackelberg context; they allow for responses by generic producers but the latter take decisions by brand-name f inns as given. Brand-name price and advertising responses to entry are shown to depend upon the properties of the reduced-form brand-name demand function. Conditions for positive price responses and negative advertising responses are derived. We also examine the implications for brand-name price levels, and for the brand-name price response to entry, of health sector trends (such as increasing HMO enrollments) that may have the effect of expanding the size of the cross-price-sensitive segment of the market. The paper concludes with a review of recent empirical research and suggestions for future work on the effects of generic entry.

"Generic Entry and the Pricing of Pharmaceuticals"

During the 1980s the share of prescriptions sold by retail pharmacies that was accounted for by generic products roughly doubled. The price response to generic entry of brand-name products has been a source of controversy. In this paper we estimate models of price responses to generic entry in the market for brand-name and generic drugs. We study a sample of 32 drugs that lost patent protection during the early to mid-1980s. Our results provide strong evidence that brand-name prices increase after entry and are accompanied by large price decreases in the price of generic drugs.

Monoclinic and triclinic phases in higher-order Devonshire theory

Devonshire theory provides a successful phenomenological description of many cubic perovskite ferroelectrics such as BaTiO3 via a sixth-order expansion of the free energy in the polar order parameter. However, the recent discovery of a novel monoclinic ferroelectric phase in the PZT system by Noheda et al. (Appl. Phys. Lett. 74, 2059 (1999)) poses a challenge to this theory. Here, we confirm that the sixth-order Devonshire theory cannot support a monoclinic phase, and consider extensions of the theory to higher orders. We show that an eighth-order theory allows for three kinds of equilibrium phases in which the polarization is confined not to a symmetry axis but to a symmetry plane. One of these phases provides a natural description of the newly observed monoclinic phase. Moreover, the theory makes testable predictions about the nature of the phase boundaries between monoclinic, tetragonal, and rhombohedral phases. A ferroelectric phase of the lowest (triclinic) symmetry type, in which the polarization is not constrained by symmetry, does not emerge until the Devonshire theory is carried to twelfth order. A topological analysis of the critical points of the free-energy surface facilitates the discussion of the phase transition sequences.Comment: 10 pages, with 5 postscript figures embedded. Uses REVTEX and epsf macros. Also available at http://www.physics.rutgers.edu/~dhv/preprints/dv_pzt/index.htm

Control of Retinal Sensitivity : I. Light and Dark Adaptation of Vertebrate Rods and Cones

Rods and cones in Necturus respond with graded hyperpolarization to test flashes spanning about 3.5 log units of intensity. Steady background levels hyperpolarize the rods, and the rod responses become progressively smaller as background level is increased. In cones, higher background levels reduce the effectiveness of test flashes, so higher ranges of test intensities are required to elicit the full range of graded responses. When backgrounds are terminated, cones return rapidly, but rods return slowly to the dark potential level. The effects of backgrounds on both rods and cones can be observed at intensities that cause negligible bleaching as determined by retinal densitometry. During dark adaptation, changes are observed in the rods and cones that are similar to those produced by backgrounds. Receptor sensitivities, derived from these results, show that rods saturate, cones obey Weber's law, and sensitization during dark adaptation follows a two-phase time-course

Atomic diffusion and mixing in old stars IV: Weak abundance trends in the globular cluster NGC 6752

Atomic diffusion in stars can create systematic trends of surface abundances with evolutionary stage. Globular clusters offer useful laboratories to put observational constraints on this theory as one needs to compare abundances in unevolved and evolved stars, all drawn from the same stellar population. In this paper, we show the results of an abundance study of stars in the globular cluster NGC6752 which shows weak but systematic abundances trends with evolutionary phase for Fe, Sc, Ti and Ca. The trends are best explained by a stellar structure model including atomic diffusion with efficient additional mixing. The model allows to correct for sub-primordial stellar lithium abundances of the stars on the Spite plateau, and to match it to the WMAP-calibrated Big-Bang nucleosynthesis predictions to within the mutual 1-sigma errors.Comment: 15 pages, 4 figures and 8 table

Transient common peroneal nerve palsy following skeletal tibial traction in a morbidly obese patient - case report of a preventable complication

Today, skeletal tibial traction remains a mainstay of initial management following high-energy, major orthopaedic lower extremity trauma. Historically utilized as definitive fracture management, recent advances in surgical technology have moved skeletal tibial traction into the realm of temporary management, with benefits including fracture reduction, pain relief, and restoration of disturbed surrounding soft tissues, lowering wound complication and compartment syndrome rates. However, no procedure is without its risks. Here, we present a case of common peroneal palsy following skeletal tibial traction placement, which resolved with subsequent pin removal. Indications, proper placement, potential etiologies, and a review of the literature are also discussed