Randomized clinical trials (RCTs) are the gold standard in producing clinical evidence of efficacy and safety of medical interventions. More recently, a new paradigm is emerging—specifically within the context of preauthorization regulatory decision‐making—for some novel uses of real‐world evidence (RWE) from a variety of real‐world data (RWD) sources to answer certain clinical questions. Traditionally reserved for rare diseases and other special circumstances, external controls (eg, historical controls) are recognized as a possible type of control arm for single‐arm trials. However, creating and analyzing an external control arm using RWD can be challenging since design and analytics may not fully control for all systematic differences (biases). Nonetheless, certain biases can be attenuated using appropriate design and analytical approaches. The main objective of this paper is to improve the scientific rigor in the generation of external control arms using RWD. Here we (a) discuss the rationale and regulatory circumstances appropriate for external control arms, (b) define different types of external control arms, and (c) describe study design elements and approaches to mitigate certain biases in external control arms. This manuscript received endorsement from the International Society for Pharmacoepidemiology (ISPE).

Over the last decades, an increase in antipsychotic (AP) prescribing and a shift from first-generation antipsychotics (FGA) to second-generation antipsychotics (SGA) among youth have been reported. However, most AP prescriptions for youth are off-label, and there are worrying long-term safety data in youth. The objective of this study was to assess multinational trends in AP use among children and adolescents. A repeated cross-sectional design was applied to cohorts from varied sources from Denmark, Germany, the Netherlands, the United Kingdom (UK) and the United States (US) for calendar years 2005/2006–2012. The annual prevalence of AP use was assessed, stratified by age group, sex and subclass (FGA/SGA). The prevalence of AP use increased from 0.78 to 1.03% in the Netherlands’ data, from 0.26 to 0.48% in the Danish cohort, from 0.23 to 0.32% in the German cohort, and from 0.1 to 0.14% in the UK cohort. In the US cohort, AP use decreased from 0.94 to 0.79%. In the US cohort, nearly all ATP dispensings were for SGA, while among the European cohorts the proportion of SGA dispensings grew to nearly 75% of all AP dispensings. With the exception of the Netherlands, AP use prevalence was highest in 15–19 year-olds. So, from 2005/6 to 2012, AP use prevalence increased in all youth cohorts from European countries and decreased in the US cohort. SGA were favoured in all countries’ cohorts.

Antidepressants are one of the most commonly prescribed psychotropic medication classes among US youths.^1,2 In the past 2 decades, there has been a marked increase in the percentage of US children and adolescents who use antidepressants (from 1.5% in 1996-1998 to 2.6% in 2010-2012).¹ This expansion of antidepressant use among youths was driven largely by a significantly more rapid increase in antidepressants prescribed to youths by pediatricians and other primary care physicians than by psychiatrists.³ For youths, several antidepressants have evidence-based indications approved by the US Food and Drug Administration, such as major depressive disorder, obsessive-compulsive disorder, and childhood enuresis,⁴ but their off-label use among youths is also not uncommon, which is a subject of concern and debate.^5,6

Real‐world evidence (RWE) has an increasing role in preapproval settings to support the approval of new medicines and indications. The main objectives of this study were to identify and characterize regulatory use cases that utilized RWE and other related observational approaches through targeted review of publications and regulatory review documents. After screening and inclusion/exclusion, the review characterized 85 regulatory applications with RWE. A total of 31 were in oncology and 54 were in non‐oncology therapeutic areas. Most were for indications in adults only (N = 42, 49.4%), while 13 were in pediatrics only (15.3%), and 30 were in both (35.3%). In terms of regulatory context, 59 cases (69.4%) were for an original marketing application, 24 (28.2%) were for label expansion, and 2 (2.4%) were for label modification. Most also received special regulatory designations (e.g., orphan indication, breakthrough therapy, fast track, conditional, and accelerated approvals). There were 42 cases that utilized RWE to support single‐arm trials. External data to support single‐arm trials were utilized in various ways across use cases, including direct matching, benchmarking, natural history studies as well as literature or previous trials. A variety of data sources were utilized, including electronic health records, claims, registries, site‐based charts. Endpoints in oncology use cases commonly included overall survival, progression‐free survival. In 13 use cases, RWE was not considered supportive/definitive in regulatory decision‐making due to design issues (e.g., small sample size, selection bias, missing data). Overall, RWE is utilized in regulatory approval processes for new indications/label expansion across various therapeutic areas with wide range of approaches. Multifaceted cross‐sector efforts are needed to further improve the quality and utility of RWE in regulatory decision‐making.

Objective:Little is known about how nurse practitioner independent practice authority (NP-IPA) influences patient care. This study examined the effect of NP-IPA on patterns of mental health–related visits provided by NPs in U.S. community health centers (CHCs).Methods:State NP regulatory information was linked to National Ambulatory Medical Care Survey data on NP- and physician-provided visits (N=61,457) in CHCs from 2006 through 2011. The proportion of NP-provided versus physician-provided mental health–related visits in states with NP-IPA was compared with the proportion in states without NP-IPA. The adjusted odds of mental health–related visits in CHCs provided by NPs in states with and without NP-IPA were compared by using multiple logistic regression models while accounting for the complex survey design.Results:Between 2006 and 2011, the odds of NP- versus physician-provided mental health–related visits in CHCs were more than two times greater in states with NP-IPA than in states with no NP-IPA (adju...