Branded vs Generic Psychotropic Medications
Branded vs Generic Psychotropic Medications
Economic considerations have led to the increasing availability and use of generic medications to replace more expensive, branded drugs wherever possible. This therapeutic exchange raises the question of whether these formulations are equivalent. As psychiatric conditions often involve long-term therapy, cost-effectiveness is particularly important in this field, but nonbranded products typically provoke mistrust. Is general caution justified? Should prescribers and patients be prepared for the possibility that exchanging a branded drug for a generic one will lead to loss of efficacy or increased adverse effects? And if there is a change in the patient’s clinical status, is it because of lack of efficacy or enhanced intolerability of the generic drug? Potential reasons for a maintained or changed clinical outcome after a branded medication has been replaced with a generic one include psychological, attitudinal, and most relevant from a regulatory perspective, pharmacokinetic factors.
The US Food and Drug Administration (FDA) states that "Any generic drug modeled after a single, brand name drug (the reference) must perform approximately the same in the body as the brand name drug. There will always be a slight, but not medically important, level of natural variability...".The level of variability accepted by the FDA is defined by pharmacokinetic measures derived from single-dose studies in healthy volunteers in a required minimum number of 24-36 participants. A generic formulation is considered bioequivalent with the innovator product if the ratios of the mean area under the curve of the serum concentration time and the ratio of the peak plasma concentration of innovator and generic drug fall within a range of 80%-125%. Because this frame allows for individual differences of -20% to +25% compared with the originator substance, considerable doubt has been cast on the concept of bioequivalence as a proxy for therapeutic equivalence.
Branded vs Generic Psychotropic Medications: Introduction
Economic considerations have led to the increasing availability and use of generic medications to replace more expensive, branded drugs wherever possible. This therapeutic exchange raises the question of whether these formulations are equivalent. As psychiatric conditions often involve long-term therapy, cost-effectiveness is particularly important in this field, but nonbranded products typically provoke mistrust. Is general caution justified? Should prescribers and patients be prepared for the possibility that exchanging a branded drug for a generic one will lead to loss of efficacy or increased adverse effects? And if there is a change in the patient’s clinical status, is it because of lack of efficacy or enhanced intolerability of the generic drug? Potential reasons for a maintained or changed clinical outcome after a branded medication has been replaced with a generic one include psychological, attitudinal, and most relevant from a regulatory perspective, pharmacokinetic factors.
The US Food and Drug Administration (FDA) states that "Any generic drug modeled after a single, brand name drug (the reference) must perform approximately the same in the body as the brand name drug. There will always be a slight, but not medically important, level of natural variability...".The level of variability accepted by the FDA is defined by pharmacokinetic measures derived from single-dose studies in healthy volunteers in a required minimum number of 24-36 participants. A generic formulation is considered bioequivalent with the innovator product if the ratios of the mean area under the curve of the serum concentration time and the ratio of the peak plasma concentration of innovator and generic drug fall within a range of 80%-125%. Because this frame allows for individual differences of -20% to +25% compared with the originator substance, considerable doubt has been cast on the concept of bioequivalence as a proxy for therapeutic equivalence.
