Assessment of Clinical Trials Supporting US Food and Drug Administration Approval of Novel Therapeutic Agents, 1995-2017

Characteristics of Clinical Studies Used for US Food and Drug Administration Supplemental Indication Approvals of Drugs and Biologics, 2017 to 2019

IMPORTANCE

After US Food and Drug Administration (FDA) approval of a new drug, sponsors can submit additional clinical data to obtain supplemental approval for use for new indications.

OBJECTIVE

To characterize pivotal trials supporting recent supplemental new indication approvals of drugs and biologics by the FDA and to compare them with pivotal trials that supported these therapeutics' original indication approvals.

DESIGN, SETTING, AND PARTICIPANTS

This is a cross-sectional study characterizing pivotal trials supporting supplemental indication approvals by the FDA between 2017 and 2019 and pivotal trials that supported these therapeutics' original indication approvals. Data analysis was performed from August to October 2020.

MAIN OUTCOMES AND MEASURES

Number and design of pivotal trials supporting both supplemental and original indication approvals.

RESULTS

From 2017 to 2019, the FDA approved 146 supplemental indications for 107 therapeutics on the basis of 181 pivotal efficacy trials. The median (interquartile range) number of trials per supplemental indication was 1 (1-1). Most trials used either placebo (77 trials [42.5%; 95% CI, 35.6%-49.8%]) or active comparators (65 trials [35.9%; 95% CI, 29.3%-43.1%]), and most of these multigroup trials were randomized (141 trials [99.3%; 95% CI, 96.0%-100.0%]) and double-blinded (106 trials [74.5%; 95% CI, 66.6%-81.0%]); 80 trials (44.2%; 95 CI, 37.2%-51.5%) used clinical outcomes as the primary efficacy end point. There was no difference between oncology therapies and those approved for other therapeutic areas to have supplemental indication approvals be based on at least 2 pivotal trials (11.5% vs 20.6%; difference, 9.1%; 95% CI, 2.9%-21.0%; P = .10). Similarly, there was no difference in use of randomization (98.3% vs 100.0%; difference, 1.7%; 95% CI, 1.6%-5.0%; P = .43) among multigroup trials, although these trials were less likely to be double-blinded (50.8% vs 92.3%; difference, 41.5%; 95% CI, 27.4%-55.5%; P < .001); overall, these trials were less likely to use either placebo or active comparators (64.9% vs 86.7%; difference, 21.8% 95% CI, 9.8%-33.9%; P < .001) or to use clinical outcomes as their primary efficacy end point (27.5% vs 61.1%; difference, 33.6%; 95% CI, 14.1%-40.9%; P < .001) and were longer (median [interquartile range], 17 [6-48] weeks vs 95 [39-146] weeks). Original approvals were more likely than supplemental indication approvals to be based on at least 2 pivotal trials (44.0% [95% CI, 33.7%-42.6%] vs 15.8% [95% CI, 10.7%-22.5%]; difference, 28.2%; 95% CI, 17.6%-39.6%; P < .001) and less likely to be supported by at least 1 trial of 12 months' duration (27.6% [95% CI, 17.9%-35.0%] vs 54.8% [95% CI, 46.7%-62.6%]; difference, 27.2%; 95% CI, 14.5%-37.8%; P < .001). Pivotal trial designs were otherwise not significantly different.

CONCLUSIONS AND RELEVANCE

These findings suggest that the number and design of the pivotal trials supporting supplemental indication approvals by the FDA varied across therapeutic areas, with the strength of evidence for cancer indications weaker than that for other indications. There was little difference in the design characteristics of the pivotal trials supporting supplemental indication and original approvals.

The Impact of Variability in Patient Exposure During Premarket Clinical Development on Postmarket Safety Outcomes

We characterized the size of the premarket safety population for 278 small-molecule new molecular entities (NMEs) and 61 new therapeutic biologics (NTBs) approved by the US Food and Drug Administration (FDA) between October 1, 2002, and December 31, 2014, evaluating the relationship of premarket safety population size to regulatory characteristics and postmarket safety outcomes. The median size of the safety population was 1,044, and was lower for NTBs than NMEs (median: 920 vs. 1,138, P = 0.04), orphan products than nonorphan products (393 vs. 1,606, P < 0.001), and for products with fast-track designation (617 vs. 1,455, P < 0.001), priority review (630 vs. 1,735, P < 0.001), and accelerated approval (475 vs. 1,164, P < 0.001), than products without that designation. The median number of postmarket safety label updates and issues added to the label were higher with larger premarket exposure among nonorphan products, but not among orphan products. Products with accelerated approval using a surrogate end point had a higher median number of safety issues added to the label than those with full approval, but this did not vary with the size of the safety population; fast-track and priority review were not associated with the number of safety issues added to the label. A smaller safety population size was associated with a longer time to first safety outcome for nonorphan products but not orphan products. For orphan and nonorphan products combined, smaller premarket safety population size is not associated with the number or timing of postmarket safety outcomes, regardless of expedited program participation.

Patient Participation in Clinical Trials of Oncology Drugs and Biologics Preceding Approval by the US Food and Drug Administration

IMPORTANCE

Several studies have estimated the financial inputs for successful drug development. Such analyses do not capture the large investment that patient study participants commit to drug development.

OBJECTIVE

To estimate the volume of patients required to achieve a first US Food and Drug Administration (FDA) approval for a new anticancer drug or biologic therapy.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included a random sample of prelicense oncology drugs and biologics with a trial site in the United States that were launched into clinical efficacy testing between January 1, 2006, and December 31, 2010. Drugs and biologics were identified using ClinicalTrials.gov registration records. Total patient enrollment was captured over an 8-year span, and each intervention was classified based on whether it received FDA approval and was deemed as having intermediate or substantial value according to the American Society of Clinical Oncology Value Framework (ASCO-VF) score. Secondarily, the association between patient numbers and intervention characteristics was tested. Data were analyzed in February 2020.

MAIN OUTCOMES AND MEASURE

The prespecified primary outcome was the number of patients enrolled in prelicense trials per FDA approval.

RESULTS

A total of 120 drugs and biologics were included in our study, with 84 (70.0%) targeted agents, 20 (16.7%) immunotherapies, and 71 (59.2%) novel agents. A total of 13 drugs and biologics (10.8%; 95% CI, 5.3%-16.8%) in our sample gained FDA approval within 8 years, of which 1 (7.7%) was deemed of intermediate value and 3 (23.1%) were deemed of substantial value using ASCO-VF scoring. Overall, 158 810 patients were enrolled in 1335 trials testing these drugs and biologics, 47 913 (30.2%) in trials that led to FDA approval and 110 897 (69.8%) in trials that did not. An estimated 12 217 (95% CI, 7970-22 215) patient study participants contributed to prelicense trials per FDA approval. The estimated number of patients needed to produce a single FDA-approved drug or biologic of intermediate or substantial ASCO-VF clinical value was 39 703 (95% CI, 19 391-177 991).

CONCLUSIONS AND RELEVANCE

The results of this cohort study make visible the substantial patient investment required for prelicense oncology drug development. Such analyses can be used to devise policies that maximize the clinical impact of research on a per-patient basis.

Exploring the Food and Drug Administration's review and approval of Entresto (sacubitril/valsartan)

Federal regulatory agencies such as the United States Food and Drug Administration review pharmacological evidence to ensure the safety and efficacy of new and repurposed pharmaceuticals prior to market approval. The discussions, disagreements and procedural decisions contained within such reviews offer unique insight into a pharmaceutical's strengths, weaknesses and opportunities, yet are often overlooked as a significant source of pharmacological information for research and development. To highlight the value of such resources, we present a case study on Entresto, a first-in-class angiotensin receptor-neprilysin inhibitor for the treatment of heart failure with reduced ejection fraction, and explore the regulatory rationale underlying its market approval. Using information extracted from Entresto's online approval package at Drugs@FDA, we explore some of the procedural complexities underlying market approval of new pharmaceuticals, discuss the broad pharmacological implications contained within regulatory agency grey literature, and highlight opportunities for future therapeutic development.

Organized structure of real-world evidence best practices: moving from fragmented recommendations to comprehensive guidance

Decision-makers have become increasingly interested in incorporating real-world evidence (RWE) into their decision-making process. Due to concerns regarding the reliability and quality of RWE, stakeholders have issued numerous recommendation documents to assist in setting RWE standards. The fragmented nature of these documents poses a challenge to researchers and decision-makers looking for guidance on what is 'high-quality' RWE and how it can be used in decision-making. We offer researchers and decision-makers a structure to organize the landscape of RWE recommendations and identify consensus and gaps in the current recommendations. To provide researchers with a much needed pathway for generating RWE, we discuss how decision-makers can move from fragmented recommendations to comprehensive guidance.

US Food and Drug Administration utilization of postmarketing requirements and postmarketing commitments, 2009-2018

BACKGROUND/AIMS

The US Food and Drug Administration outlines clinical studies as postmarketing requirements and commitments to be fulfilled following approval of new drugs and biologics ("therapeutics"). Regulators have increasingly emphasized lifecycle evaluation of approved therapeutics, and postmarketing studies are intended to advance our understanding of therapeutic safety and efficacy. However, little is known about the indications that clinical studies outlined in postmarketing requirements and commitments investigate, including whether they are intended to generate evidence for approved or other clinical indications. Therefore, we characterized US Food and Drug Administration postmarketing requirements and commitments for new therapeutics approved from 2009 to 2018.

METHODS

We conducted a cross-sectional study of all novel therapeutics, including small-molecule drugs and biologics, receiving original US Food and Drug Administration approval from 2009 to 2018, using approval letters accessed through the Drug@FDA database. Outcomes included the number and characteristics of US Food and Drug Administration postmarketing requirements and commitments for new therapeutics at original approval, including the types of studies outlined, the indications to be investigated, and the clinical evidence to be generated.

RESULTS

From 2009 to 2018, the US Food and Drug Administration approved 343 new therapeutics with 1978 postmarketing requirements and commitments. Overall, 750 (37.9%) postmarketing requirements and commitments outlined clinical studies. For 71 of 343 (20.7%) therapeutics, no postmarketing requirements or commitments for clinical studies were outlined, while at least 1 was outlined for 272 (79.3%; median 2 (interquartile range: 1-4)). Among these 272 therapeutics, the number of postmarketing requirements and commitments for clinical studies per therapeutic did not change from 2009 (median: 2 (interquartile range: 1-4)) to 2018 (median: 2 (interquartile range: 1-3)). Among the 750 postmarketing requirements and commitments for clinical studies, 448 (59.7%) outlined new prospective cohort studies, registries, or clinical trials, while the remainder outlined retrospective studies, secondary analyses, or completion of ongoing studies. Although 455 (60.7%) clinical studies investigated only original approved therapeutic indications, 123 (16.4%) enrolled from an expansion of the approved disease population and 61 (8.1%) investigated diseases unrelated to approved indications.

CONCLUSIONS

The US Food and Drug Administration approves most new therapeutics with at least 1 postmarketing requirement or commitment for a clinical study, and outlines investigations of safety or efficacy for both approved and unapproved indications. The median number of 2 clinical studies outlined has remained relatively constant over the last decade. Given increasing emphasis by the US Food and Drug Administration on faster approval and lifecycle evaluation of therapeutics, these findings suggest that more postmarketing requirements and commitments may be necessary to address gaps in the clinical evidence available for therapeutics at approval.

Regulatory reliance to approve new medicinal products in Latin American and Caribbean countries

Objective.

To describe the current status of regulatory reliance in Latin America and the Caribbean (LAC) by assessing the countries’ regulatory frameworks to approve new medicines, and to ascertain, for each country, which foreign regulators are considered as trusted regulatory authorities to rely on.

Methods.

Websites from LAC regulators were searched to identify the official regulations to approve new drugs. Data collection was carried out in December 2019 and completed in June 2020 for the Caribbean countries. Two independent teams collected information regarding direct recognition or abbreviated processes to approve new drugs and the reference (trusted) regulators defined as such by the corresponding national legislation.

Results.

Regulatory documents regarding marketing authorization were found in 20 LAC regulators’ websites, covering 34 countries. Seven countries do not accept reliance on foreign regulators. Thirteen regulatory authorities (Argentina, Colombia, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Mexico, Panama, Paraguay, Peru, Uruguay, and the unique Caribbean Regulatory System for 15 Caribbean States) explicitly accept relying on marketing authorizations issued by the European Medicines Agency, United States Food and Drug Administration, and Health Canada. Ten countries rely also on marketing authorizations from Australia, Japan, and Switzerland. Argentina, Brazil, Chile, and Mexico are reference authorities for eight LAC regulators.

Conclusions.

Regulatory reliance has become a common practice in the LAC region. Thirteen out of 20 regulators directly recognize or abbreviate the marketing authorization process in case of earlier approval by a regulator from another jurisdiction. The regulators most relied upon are the European Medicines Agency, United States Food and Drug Administration, and Health Canada.

Regulators, Pivotal Clinical Trials, and Drug Regulation in the Age of COVID-19

Medicine regulators rely on pivotal clinical trials to make decisions about approving a new drug, but little is known about how they judge whether pivotal trials justify the approval of new drugs. We explore this issue by looking at the positions of 3 major regulators: the European Medicines Agency, Food and Drug Administration, and Health Canada. Here we report their views and the implications of those views for the approval process. On various points, the 3 regulators are ambiguous, consistent, and demonstrate flexibility. The range of views may well reflect different regulatory cultures. Although clinical trial information from pivotal trials is becoming more available, regulators are still reluctant to provide detailed information about how that information is interpreted. As medicines and vaccines come up for approval for treatment of COVID-19, transparency in how pivotal trials are interpreted will be critical in determining how these treatments should be used.

Development and Use of Gene Therapy Orphan Drugs-Ethical Needs for a Broader Cooperation Between the Pharmaceutical Industry and Society

Gene therapy orphan medicinal products constitute a unique group of new drugs which in case of hereditary diseases are usually administered only once at an early age, in the hope to provide sufficient gene product to last for the entire life of the patients. The combination of an exceptionally large single payment and the life-long clinical follow-up needed for understanding the long-term benefits and safety of gene therapy, represent new types of scientific, financial, social and ethical challenges for the pharmaceutical industry, regulators and society. With special consideration of the uniqueness and importance of gene therapy, the authors propose a three points plan for a close cooperation between the pharmaceutical industry and society to develop orphan gene therapy. (1) In fully transparent health technology negotiations a close and long-lasting, contractually fixed cooperation should be established between the manufacturers and local health-care stakeholders for sharing the medical and scientific benefits, the financial risks as well as the burdens of the post-authorization clinical and regulatory development. (2) The parties should agree on a fair, locally affordable drug price without the usually very high premium price calculated to compensate for the low number of patients. In case of high manufacturing costs, the companies should offer prolonged, 15–20 years long payment by installment with risk-sharing, especially considering that the late outcome of the treatment is unknown. Society should assist scientifically and financially organizing a specific patient registry, treatment in specialized hospitals and adequate long-term follow-up of patients, the coordinated management of financial transactions related to the risk sharing program. (3) The post-authorization treatment and prolonged observation of additional new cases coordinated by society should provide real world data needed for the modern complex regulatory evaluation of gene therapy products by the competent authorities. We assume that fair sharing of the benefits and risks as well as a well-organized cooperation of society with the industry in collecting real world evidence might result in better drug evaluation and improved accessibility due to lower prices. The outlined concept might support gene therapy more efficiently than the presently requested outstandingly high prices.

Exact change point detection with improved power in small-sample binomial sequences

To detect a change in the probability of a sequence of independent binomial random variables, a variety of asymptotic and exact testing procedures have been proposed. Whenever the sample size or the event rate is small, asymptotic approximations of maximally selected test statistics have been shown to be inaccurate. Although exact methods control the type I error rate, they can be overly conservative due to the discreteness of the test statistics in these situations. We extend approaches by Worsley and Halpern to develop a test that is less discrete to increase the power. Building on ideas from binary segmentation, the proposed test utilizes unused information in the binomial sequences to add a new ordering to test statistics that are of equal value. The exact distributions are derived under side conditions that arise in hypothetical segmentation steps and do not depend on the type of test statistic used (e.g., log likelihood ratio, cumulative sum, or Fisher's exact test). Using the proposed exact segmentation procedure, we construct a change point test and prove that it controls the type-I-error rate at any given nominal level. Furthermore, we prove that the new test is uniformly at least as powerful as Worsley's exact test. In a Monte Carlo simulation study, the gain in power can be remarkable, especially in scenarios with small sample size. Giving a clinical database example about pin site infections and an example assessing publication bias in neuropsychiatric drug research, we demonstrate the wide-ranging applicability of the test.

Association between FDA and EMA expedited approval programs and therapeutic value of new medicines: retrospective cohort study

OBJECTIVE

To characterize the therapeutic value of new drugs approved by the US Food and Drug Administration (FDA) and European Medicines Agency (EMA) and the association between these ratings and regulatory approval through expedited programs.

DESIGN

Retrospective cohort study.

SETTING

New drugs approved by the FDA and EMA between 2007 and 2017, with follow-up through 1 April 2020.

DATA SOURCES

Therapeutic value was measured using ratings of new drugs by five independent organizations (Prescrire and health authorities of Canada, France, Germany, and Italy).

MAIN OUTCOME MEASURES

Proportion of new drugs rated as having high therapeutic value; association between high therapeutic value rating and expedited status.

RESULTS

From 2007 through 2017, the FDA and EMA approved 320 and 268 new drugs, respectively, of which 181 (57%) and 39 (15%) qualified for least one expedited program. Among 267 new drugs with a therapeutic value rating, 84 (31%) were rated as having high therapeutic value by at least one organization. Compared with non-expedited drugs, a greater proportion of expedited drugs were rated as having high therapeutic value among both FDA approvals (45% (69/153) v 13% (15/114); P<0.001) and EMA approvals (67% (18/27) v 27% (65/240); P<0.001). The sensitivity and specificity of expedited program for a drug being independently rated as having high therapeutic value were 82% (95% confidence interval 72% to 90%) and 54% (47% to 62%), respectively, for the FDA, compared with 25.3% (16.4% to 36.0%) and 90.2% (85.0% to 94.1%) for the EMA.

CONCLUSIONS

Less than a third of new drugs approved by the FDA and EMA over the past decade were rated as having high therapeutic value by at least one of five independent organizations. Although expedited drugs were more likely than non-expedited drugs to be highly rated, most expedited drugs approved by the FDA but not the EMA were rated as having low therapeutic value.

Surrogate Endpoints in Health Technology Assessment: An International Review of Methodological Guidelines

In the drive towards faster patient access to treatments, health technology assessment (HTA) agencies are increasingly faced with reliance on evidence from surrogate endpoints, leading to increased decision uncertainty. This study undertook an updated survey of methodological guidance for using surrogate endpoints across international HTA agencies. We reviewed HTA and economic evaluation methods guidance from European, Australian and Canadian HTA agencies. We considered how guidelines addressed the methods for handling surrogate endpoints, including (1) level of evidence, (2) methods of validation, and (3) thresholds of acceptability. Across the 73 HTA agencies surveyed, 29 (40%) had methodological guidelines that made specific reference to consideration of surrogate outcomes. Of the 45 methods documents analysed, the majority [27 (60%)] were non-technology specific, 15 (33%) focused on pharmaceuticals and three (7%) on medical devices. The principles of the European network for Health Technology Assessment (EUnetHTA) guidelines published in 2015 on the handling of surrogate endpoints appear to have been adopted by many European HTA agencies, i.e. preference for final patient-relevant outcomes and reliance on surrogate endpoints with biological plausibility and epidemiological evidence of the association between the surrogate and final endpoint. Only a small number of HTA agencies (UK National Institute for Care and Excellence; the German Institute for Medical Documentation and Information and Institute for Quality and Efficiency in Health Care; the Australian Pharmaceutical Benefits Advisory Committee; and the Canadian Agency for Drugs and Technologies in Health) have developed more detailed prescriptive criteria for the acceptance of surrogate endpoints, e.g. meta-analyses of randomised controlled trials showing strong association between the treatment effect on the surrogate and final outcomes. As the decision uncertainty associated with reliance on surrogate endpoints carries a risk to patients and society, there is a need for HTA agencies to develop more detailed methodological guidance for consistent selection and evaluation of health technologies that lack definitive final patient-relevant outcome evidence at the time of the assessment.

Pharmaceuticals as a market for "lemons": Theory and practice

Drawing on economic theory and institutional analysis, this paper reframes Akerlof's theory of how a market for lemons operates and argues that each of the many markets for lemons must be studied empirically to document how different stakeholders cope with the problems of information asymmetry, secrecy, and power. Such markets are a new field for sociological analysis. To illustrate, the paper characterizes pharmaceuticals as a multi-tier market of information asymmetry in which actors in each tier have substantial control over how much they disclose about hidden risks of harm. Such a market rewards the production and sale of "lemons." Current incentives and institutional practices reward developing a large number of barely therapeutically innovative drugs and ignoring their often hidden or understated harmful side effects. They reward designing and executing substandard, biased trials that mislead the FDA and regulators abroad to approve new drugs without clear evidence of their degree of harm. Approved drugs are likely to be "lemons" but promoted as "safe and effective." The result is substantial hospitalizations and deaths from adverse drug reactions. A "risk proliferation syndrome" of institutional practices maximizes sales, profits, and exposure to toxic side effects. An "inverse benefit law" of marketing operates as companies try to maximize sales. The probability of benefits decreases but the chances of lemons adverse events do not. The details presented here deepen understanding of how markets for lemons thrive on information asymmetry, secrecy, and power. Lessons can be applied to other markets.