Drug treatment effects on disease progression

Degenerative diseases are characterized by a worsening of disease status ov er time. The rate of deterioration is determined by the natural rate of pro gression of the disease and by the effect of drug treatments. A goal of dru g treatment is to slow disease progression. Drug treatments can be categori zed as symptomatic or protective. Symptomatic treatments do not affect the rate of disease progression whereas protective treatments have the ability to slow disease progression down. Many current methods for describing disea se progression have two common drawbacks: a linear relationship between tim e and disease status is assumed, and within- and between-subject variabilit y is ignored. Disease progress models combined with pharmacokinetic-pharmac odynamic models and hierarchical random effects statistical models provide insights into understanding the time course and management of degenerative disease.