Influencers of generic drug utilization: A systematic review

Howard, Jennifer; Harris, Ilene; Frank, Gavriella; Kiptanui, Zippora; Qian, Jingjing; Hansen, Richard A

doi:10.1016/j.sapharm.2017.08.001

Cited by 57 publications

(72 citation statements)

References 77 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This phenomenon is expected considering the identical active pharmaceutical ingredients and indications, as these brand–generic alternatives are near perfect active comparators. Additional confounders that may lead to selection of trade over generic, such as socioeconomic status, insurance coverage/formularies, physician or patient preferences, and so on are not measured and could not be controlled given the data sources . However, this analysis allows for simulation of using pharmacy‐only utilization data (eg, IQVIA retail pharmacy data), which would lack additional demographic or clinical data.…”

Section: Discussionmentioning

confidence: 99%

“…The US Food and Drug Administration (FDA) requires pharmacokinetic (PK) bioequivalence of generic drugs to brand name drugs to ensure therapeutic equivalence of generic products when substituting for brand drug products . However, evidence suggests that there are sometimes concerns from health practitioners and patients suggesting potential “bio in equivalence” of generic drug products and suggests the need for postmarketing surveillance of both brand and generic versions of medications …”

mentioning

confidence: 99%

See 1 more Smart Citation

Real‐World Data Approaches for Early Detection of Potential Safety and Effectiveness Signals for Generic Substitution: A Metoprolol Extended‐Release Case Study

Brown

Henriksen

Vozmediano

et al. 2019

The Journal of Clinical Pharma

View full text Add to dashboard Cite

Real‐world spontaneous adverse event reports and administrative health care data were utilized as one part of a multipronged approach to verify surveillance signals related to generic drug formulations. This study used metoprolol succinate extended release as a historic case example from which to develop an analytic framework. The US Food and Drug Administration Adverse Event Reporting System was utilized for disproportionality analyses and to identify outcomes of interest. Claims data were analyzed for generic uptake, proportion of prescriptions with “dispense as written” orders, time to discontinuation or switching, and relative rates of clinical events. Adverse Event Reporting System data showed that the Medical Dictionary for Regulatory Activities terms for product quality were higher for generic metoprolol cases and that a number of clinical events were increased that could be side effects of high or low variability in drug levels. Compared to amlodipine‐benazepril, which also had a first‐approved generic at the same time, market share data showed that metoprolol succinate had lower utilization and more prescriptions written as dispense as written. Switching and discontinuation were generally higher for metoprolol users compared to amlodipine‐benazepril users. Finally, clinical event rates were generally higher for generic versus brand metoprolol but lower for the same comparison for amlodipine‐benazepril users. In the claims‐based analyses, the 90‐day period immediately after generic entry provided stronger signal capture than using the entire study period. This analytic framework can be implemented to actively monitor new generic formulations for potential bioequivalence failures. Signals from these analyses require confirmation (eg, via pharmacometric analyses) to be informative for regulatory action.

show abstract

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

Real‐World Data Approaches for Early Detection of Potential Safety and Effectiveness Signals for Generic Substitution: A Metoprolol Extended‐Release Case Study

Brown

Henriksen

Vozmediano

et al. 2019

The Journal of Clinical Pharma

View full text Add to dashboard Cite

show abstract

“…Research by Coscelli () indicated that in markets with little price variation among branded drugs, physician prescribing habits lead to persistence in the market shares of competing drugs over time. Finally, Howard et al () found that generic drugs were prescribed more often by general physicians (as opposed to specialists), residents (as opposed to attending physicians), and younger physicians. E‐prescribing has also been associated with higher generic prescription‐fill rates (Howard et al ).…”

Section: Background and Literature Reviewmentioning

confidence: 99%

“…Finally, Howard et al () found that generic drugs were prescribed more often by general physicians (as opposed to specialists), residents (as opposed to attending physicians), and younger physicians. E‐prescribing has also been associated with higher generic prescription‐fill rates (Howard et al ). In fact, Malhotra et al () found generic prescriptions more than doubled when clinical decision support systems defaulted to the generic drug.…”

Section: Background and Literature Reviewmentioning

confidence: 99%

See 1 more Smart Citation

Estimates of the Price Elasticity of Switching Between Branded and Generic Drugs

Terrizzi

Meyerhoefer

2019

Contemporary Economic Policy

View full text Add to dashboard Cite

We estimate price elasticities of switching from branded to generic drugs for two widely used drugs: Prozac and Zocor. We find the price elasticity of switching varies by drug and is between 0.01 and 0.10. While elasticity estimates for Zocor are robust to the inclusion of controls for supply‐side factors, those for Prozac are not. Our results indicate consumers in managed care plans are most responsive to differences in out‐of‐pocket (OOP) cost, and we estimate that a 10% increase in the OOP cost difference between Zocor and generic Simvastatin increases an individual's probability of switching to the generic by approximately 0.3%. This would result in a modest total savings of $36,700 among our sample of 114,218 privately insured Zocor users. Our finding that individuals are relatively unresponsive to the lower prices caused by generic introduction implies that policies targeting supply‐side behavior are likely to have a larger effect on generic uptake than price‐based inducements. If generic‐uptake did occur immediately within the first 18 months after generic introduction, the total savings among individuals and insurance companies within our sample would be approximately $7 million for Zocor and $255,000 for Prozac. (JEL I11, I18)

show abstract

Factors Associated With Prescriptions for Branded Medications in the Medicare Part D Program

2021

View full text Add to dashboard Cite

Key Points Question What factors are associated with the dispensing of branded medications in the Medicare Part D program? Findings This cross-sectional study of 169 million Medicare part D multisource prescription drug claims in 2017 revealed that branded drugs were dispensed because of prescriber request 16.9% of the time and because of patient request 13.5% of the time. The projected savings for switching the branded drugs requested by prescribers to generics were $997 million for Medicare and $161 million for patients; projected savings for switching patient-requested drugs were $673 million for Medicare and $109 million for patients. Meaning Branded dispensing of multisource drugs requested by prescribers or patients was associated with increased spending for the Medicare program and patients.

show abstract

Influencers of generic drug utilization: A systematic review

Abstract: Patients, physicians, pharmacists, formulary managers, and policymakers play an important role in generic drug use. Understanding the factors influencing generic drug use can help guide future policy, education, and practice interventions to increase generic drug use.

Cited by 57 publications

References 77 publications

Real‐World Data Approaches for Early Detection of Potential Safety and Effectiveness Signals for Generic Substitution: A Metoprolol Extended‐Release Case Study

Real‐World Data Approaches for Early Detection of Potential Safety and Effectiveness Signals for Generic Substitution: A Metoprolol Extended‐Release Case Study

Estimates of the Price Elasticity of Switching Between Branded and Generic Drugs

Factors Associated With Prescriptions for Branded Medications in the Medicare Part D Program

Contact Info

Product

Resources

About