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Background To the extent that outcomes are mediated through negative perceptions of generics (the nocebo effect), observational studies comparing brand-name and generic drugs are susceptible to bias favoring the brand-name drugs. We used authorized generic (AG) products, which are identical in composition and appearance to brand-name products but are marketed as generics, as a control group to address this bias in an evaluation aiming to compare the effectiveness of generic versus brand medications. Methods and findings For commercial health insurance enrollees from the US, administrative claims data were derived from 2 databases: (1) Optum Clinformatics Data Mart (years: 2004–2013) and (2) Truven MarketScan (years: 2003–2015). For a total of 8 drug products, the following groups were compared using a cohort study design: (1) patients switching from brand-name products to AGs versus generics, and patients initiating treatment with AGs versus generics, where AG use proxied brand-name use, addressing negative perception bias, and (2) patients initiating generic versus brand-name products (bias-prone direct comparison) and patients initiating AG versus brand-name products (negative control). Using Cox proportional hazards regression after 1:1 propensity-score matching, we compared a composite cardiovascular endpoint (for amlodipine, amlodipine-benazepril, and quinapril), non-vertebral fracture (for alendronate and calcitonin), psychiatric hospitalization rate (for sertraline and escitalopram), and insulin initiation (for glipizide) between the groups. Inverse variance meta-analytic methods were used to pool adjusted hazard ratios (HRs) for each comparison between the 2 databases. Across 8 products, 2,264,774 matched pairs of patients were included in the comparisons of AGs versus generics. A majority (12 out of 16) of the clinical endpoint estimates showed similar outcomes between AGs and generics. Among the other 4 estimates that did have significantly different outcomes, 3 suggested improved outcomes with generics and 1 favored AGs (patients switching from amlodipine brand-name: HR [95% CI] 0.92 [0.88–0.97]). The comparison between generic and brand-name initiators involved 1,313,161 matched pairs, and no differences in outcomes were noted for alendronate, calcitonin, glipizide, or quinapril. We observed a lower risk of the composite cardiovascular endpoint with generics versus brand-name products for amlodipine and amlodipine-benazepril (HR [95% CI]: 0.91 [0.84–0.99] and 0.84 [0.76–0.94], respectively). For escitalopram and sertraline, we observed higher rates of psychiatric hospitalizations with generics (HR [95% CI]: 1.05 [1.01–1.10] and 1.07 [1.01–1.14], respectively). The negative control comparisons also indicated potentially higher rates of similar magnitude with AG compared to brand-name initiation for escitalopram and sertraline (HR [95% CI]: 1.06 [0.98–1.13] and 1.11 [1.05–1.18], respectively), suggesting that the differences observed between brand and generic users in these outcomes are likely explained by either residual confounding or generic perception bias. Limitations of this study include potential residual confounding due to the unavailability of certain clinical parameters in administrative claims data and the inability to evaluate surrogate outcomes, such as immediate changes in blood pressure, upon switching from brand products to generics. Conclusions In this study, we observed that use of generics was associated with comparable clinical outcomes to use of brand-name products. These results could help in promoting educational interventions aimed at increasing patient and provider confidence in the ability of generic medicines to manage chronic diseases., Rishi Desai & colleagues use data from two large US commercial insurance databases to compare brand-name versus authorised generic drugs and negative perception bias., Author summary Why was this study done? Empirical research investigating comparative outcomes of generic versus brand-name drug use in routine-care patient populations is limited. Many patients and providers perceive generics to be less effective and less safe than their brand-name counterparts. To the extent that outcomes are mediated through negative perceptions (the nocebo effect), observational studies comparing brand-name and generic drugs are susceptible to bias favoring the brand-name drugs. This study was done to assess the comparative effectiveness of generic versus brand-name drugs, while addressing the potential for perception bias. What did the researchers do and find? The authors used data from 2 large US commercial insurance databases to assess authorized generics, which are chemically identical to and share the same appearance as brand-name products, as proxies for brand-name drug use to account for potential bias due to negative perceptions towards generics in comparing the effectiveness of 8 brand-name versus generic products. After analyzing data from more than 3.5 million patients, the authors observed that use of generics provided comparable clinical outcomes to those of the brand-name products for chronic conditions including diabetes (glipizide), hypertension (amlodipine, amlodipine-benazepril, and quinapril), osteoporosis (alendronate and calcitonin salmon), and depression and anxiety (escitalopram and sertraline). What do these findings mean? These results may guide the development of educational interventions to address physicians’ and patients’ negative perceptions of generics and to increase awareness regarding the equivalence of generic and brand-name drugs.

Background Some experts have proposed combating rising drug prices by promoting brand–brand competition, a situation that is supposed to arise when multiple US Food and Drug Administration (FDA)-approved brand-name products in the same class are indicated for the same condition. However, numerous reports exist of price increases following the introduction of brand-name competition, suggesting that it may not be effective. We performed a systematic literature review of the peer-reviewed health policy and economics literature to better understand the interplay between new drug entry and intraclass drug prices. Methods and findings We searched PubMed and EconLit for original studies on brand–brand competition in the US market published in English between January 1990 and April 2019. We performed a qualitative synthesis of each study’s data, recording its primary objective, methodology, and results. We found 10 empirical investigations, with 1 study each on antihypertensives, anti-infectives, central nervous system stimulants for attention deficit/hyperactivity disorder, disease-modifying therapies for multiple sclerosis, histamine-2 (H2) blockers, and tumor necrosis factor (TNF) inhibitors; 2 studies on cancer medications; and 2 studies on all marketed or new drugs. None of the studies reported that brand–brand competition lowers list prices of existing drugs within a class. The findings of 2 studies suggest that such competition may help restrain how new drug prices are set. Other studies found evidence that brand–brand competition was mediated by the relative quality of competing drugs and the extent to which they are marketed, with safer or more effective new drugs and greater marketing associated with higher intraclass list prices. Our investigation was limited by the studies’ use of list rather than net prices and the age of some of the data. Conclusions Our findings suggest that policies to promote brand–brand competition in the US pharmaceutical market, such as accelerating approval of non-first-in-class drugs, will likely not result in lower drug list prices absent additional structural reforms., Ameet Sarpatwari and colleagues assess market competition among brand-name drugs with similar therapeutic effects., Author summary Why was this study done? US prescription drug spending has increased sharply over the last decade, with higher launch prices of new brand-name drugs and routine price increases on older brand-name drugs. Promoting greater “brand–brand” competition, which occurs between brand-name drugs indicated for the same condition, has been proposed to address high drug prices. Many examples exist of price increases following the introduction of brand-name competition, casting doubt on the effectiveness of brand–brand competition in the pharmaceutical market. What did the researchers do and find? We systematically reviewed published research on brand–brand competition and found 10 studies evaluating a wide range of drug classes. None of the 10 studies found that brand–brand competition lowers the published (“list”) price of existing brand-name drugs within a class. We found that brand–brand competition may help restrain launch list prices and that the effect of brand–brand competition may be mediated by the relative drug quality and marketing, with safer or more effective new drugs and greater marketing associated with higher intraclass list prices. What do these findings mean? Barriers to brand–brand competition having a greater impact on list prices include the following: physicians not prescribing the most cost-effective treatments due to lack of knowledge, constraints on payers’ abilities to set one manufacturer against another in drug price negotiations, and the misdirected incentive for pharmacy benefits managers (PBMs) to accept high list prices of brand-name drugs. Greater brand–brand competition alone will likely not lower list prices of brand-name drugs.

Ameet Sarpatwari and Aaron Kesselheim explore whether stripping branded drugs of trademark protection would improve the efficiency and fairness of health care.

Aaron Kesselheim and colleagues examine potential strategies to promote greater prescribing of generic drugs and follow-on biologics.