U.S. Food and Drug Administration Reasoning in Approval Decisions When Efficacy Evidence Is Borderline, 2013-2018

Putting meat on the bone: how to fast-track innovative medicines to those who need them and generate data to justify continued use

Regulatory agencies worldwide have taken significant steps to expedite approval and market authorization of medicines based on their potential to address areas of significant unmet medical need and severe disease burden. However, initial approval of such medicines is often accompanied by limited evidence of benefit, posing a conundrum for payers and health systems who may desire greater certainty of their value. This paper describes a system of "accelerated access" to manage these tensions and coordinate activities across stakeholders, based on discussions held at a multi-stakeholder convening in June 2023. We focus on 6 core, near-term actions that can be taken to improve the current system: clarifying criteria for expedited regulatory approval, enhancing stakeholder coordination, creating expedited pathways in payer and health technology assessment settings, developing joint regulatory/payer/health technology assessment guidance on study design and data needs, linking pricing policy to data uncertainty, and improving patient and public understanding of the processes involved as well as the risks and benefits of the relevant medicines. Many of these actions will require additional resources and personnel, and some will necessitate unprecedented levels of coordination. Nevertheless, each action is designed to work with minimal adjustments to the current system rather than demanding an entirely new approach.

Regulatory histories of recently withdrawn ovarian cancer treatment indications of 3 PARP inhibitors in the US and Europe: lessons for the accelerated approval pathway

Background

Withdrawals of drug indications may reveal potential inadequacies in the regulatory approval processes of new drugs. Understanding potential weaknesses of the regulatory approval process is paramount given the increasing use of expedited pathways. In this paper, we focus on three poly-ADP-ribose polymerase inhibitors (olaparib, rucaparib and niraparib) for the treatment of women with heavily pretreated, recurrent ovarian cancer, which were eventually withdrawn.

Methods

We use a comparative case study approach to evaluate the regulatory histories of these drug indications in the US and Europe.

Results

Two drug indications benefited from the FDA's accelerated approval pathway, which explicitly lowers the bar for evidence of efficacy at the time of approval. Following accelerated approval, manufacturers are mandated to conduct post-marketing studies to confirm clinical benefit. The FDA granted accelerated approval to olaparib and rucaparib based on data on surrogate endpoints and converted the approval to regular approval after the submission of additional data on surrogate endpoints from one of two required confirmatory trials, that is, without data on clinical benefit. Niraparib directly received regular approval based only on data on a surrogate endpoint. By contrast, the EMA granted conditional marketing authorisation to rucaparib and was quicker to restrict usage than the FDA.

Conclusion

The regulatory histories of these drug indications highlight the need to reform the accelerated approval pathway by ensuring that post-marketing requirements are followed, and that regular approval is only based on evidence of clinical benefit.

Strategies of immobilizing BMP-2 with 3D-printed scaffolds to improve osteogenesis

The management and definitive treatment of critical-size bone defects in severe trauma, tumor resection and congenital malformation are troublesome for orthopedic surgeons and patients worldwide without recognized good treatment strategies. Researchers and clinicians are working to develop new strategies to treat these problems. This review aims to summarize the techniques used by additive manufacturing scaffolds loaded with BMP-2 to promote osteogenesis and to analyze the current status and trends in relevant clinical translation. Optimize composite scaffold design to enhance bone regeneration through printing technology, material selection, structure design and loading methods of BMP-2 to advance the clinical therapeutic bone repair field.

US Food and Drug Administration Approval of Drugs Not Meeting Pivotal Trial Primary End Points, 2018-2021

This cross-sectional study determines the frequency of and rationale for US Food and Drug Administration (FDA) approval of drugs not meeting pivotal trial primary efficacy end points.

A Generalization of the Two Trials Paradigm

The two trials paradigm plays a prominent role in drug development and has been widely and controversially discussed. Its purpose is to ensure replicability or substantiation of study results. This note investigates a simple generalization of the paradigm to more than two trials that preserves the project wise type-I error rate and power.

Application of Bayesian approaches in drug development: starting a virtuous cycle

The pharmaceutical industry and its global regulators have routinely used frequentist statistical methods, such as null hypothesis significance testing and p values, for evaluation and approval of new treatments. The clinical drug development process, however, with its accumulation of data over time, can be well suited for the use of Bayesian statistical approaches that explicitly incorporate existing data into clinical trial design, analysis and decision-making. Such approaches, if used appropriately, have the potential to substantially reduce the time and cost of bringing innovative medicines to patients, as well as to reduce the exposure of patients in clinical trials to ineffective or unsafe treatment regimens. Nevertheless, despite advances in Bayesian methodology, the availability of the necessary computational power and growing amounts of relevant existing data that could be used, Bayesian methods remain underused in the clinical development and regulatory review of new therapies. Here, we highlight the value of Bayesian methods in drug development, discuss barriers to their application and recommend approaches to address them. Our aim is to engage stakeholders in the process of considering when the use of existing data is appropriate and how Bayesian methods can be implemented more routinely as an effective tool for doing so.

Aspiring to Reasonableness in Accelerated Approval: Anticipating and Avoiding the Next Aducanumab

The US Food and Drug Administration's decisions about drug approval-though guided by science, as well as relevant statutes, regulations, and guidance documents-reflect normative judgments about how the agency should exercise its discretion. This is particularly true in the context of the "accelerated approval" pathway, where the agency must balance speeding to market drugs for patients with unmet needs before they have been proven to work and ensuring confidence about the benefits and risks of those drugs. A key challenge in evaluating normative judgments such as these is that reasonable people can disagree, rendering it difficult to proclaim with certainty that a particular decision is right or wrong. Therefore, we propose that it is preferable to ask whether a decision is reasonable. A decision is reasonable when it transparently, comprehensively, and fairly balances the interests of affected parties, within the parameters of the decision maker's legal authority. If a decision achieves these three qualities, it can be viewed as legitimate and worthy of trust and confidence, regardless of whether one agrees with the particular outcome. We recommend that the Food and Drug Administration adopt procedural protections to promote reasonableness in four domains affecting accelerated approval decisions: pathway gatekeeping, endpoint selection, stakeholder engagement, and deliberation. This should aid the agency in minimizing controversies, such as that surrounding the 2021 approval of aducanumab (Aduhelm; Biogen).

Unwanted Advice? Frequency, Characteristics, And Outcomes Of Negative Advisory Committee Votes For FDA-Approved Drugs

Substantial controversy arose in 2021 when the Food and Drug Administration (FDA) approved the Alzheimer's disease drug aducanumab (Aduhelm) under its accelerated approval program despite a nearly unanimous negative advisory committee vote. Advisory committees are convened before some FDA decisions to provide insight for the agency's decision-making process. To understand the frequency, characteristics, and outcomes of cases in which the FDA authorizes a drug against the recommendations of an advisory committee, we reviewed all FDA advisory committee referrals for new drugs approved during the period 2010-21. The fraction of approved drugs that had been referred to an advisory committee decreased from 55 percent to 6 percent annually, with FDA approvals of negatively reviewed drugs occurring about once a year. Qualitative analysis of committee meetings revealed variability in the substance and wording of key voting questions. Reforms such as transparent criteria for when a drug should be subject to external scrutiny, consistent wording of voting questions, and clear regulatory responses to negative recommendations can better ensure public confidence in the FDA approval process.

Conditional Drug Approval as a Path to Market for Oncology Drugs in Canada: Challenges and Recommendations for Assessing Eligibility and Regulatory Responsiveness

International drug regulators use conditional drug approval mechanisms to facilitate faster patient access to drugs based on a lower evidentiary standard typically required of drug approvals. Faster and earlier access is justified by limiting eligibility to drugs intended for serious and life-threatening diseases and by requiring post-market evidence collection to confirm clinical benefit. One such mechanism in Canada, the Notice of Compliance with Conditions (NOC/c) policy, was introduced in 1998. Today, most of the drugs approved under the NOC/c policy are for oncology indications. We analyze oncology drugs approvals under the NOC/c policy to inform discussions of two tradeoffs applied to conditional drug approvals, eligibility criteria and post-market evidence. Our analysis informs recommendations for Canada's proposed regulatory reforms approach to conditional approvals pathways. Our analysis demonstrates that under the current policy, eligibility criteria are insufficiently defined, resulting in their inconsistent application by Health Canada. Regulatory responsiveness to post-market evidence from post-market clinical trial and foreign jurisdiction regulatory decisions is slow and insufficient. In the absence of sufficient regulatory responsiveness, physicians and patients must make clinical decisions without the benefit of the best available evidence. Together, our analysis of the two core tradeoffs in Canada's conditional drug approval provides insight to inform the further development of Canada's proposed agile regulatory approach to drugs and devices that will expand the use of terms and conditions.

Improving Translational Paradigms in Drug Discovery and Development

Despite improved knowledge regarding disease causality, new drug targets, and enabling technologies, the attrition rate for compounds entering clinical trials has remained consistently high for several decades, with an average 90% failure rate. These failures are manifested in an inability to reproduce efficacy findings from animal models in humans and/or the occurrence of unexpected safety issues, and reflect failures in T1 translation. Similarly, an inability to sequentially demonstrate compound efficacy and safety in Phase IIa, IIb, and III clinical trials represents failures in T2 translation. Accordingly, T1 and T2 translation are colloquially termed 'valleys of death'. Since T2 translation dealt almost exclusively with clinical trials, T3 and T4 translational steps were added, with the former focused on facilitating interactions between laboratory- and population-based research and the latter on 'real world' health outcomes. Factors that potentially lead to T1/T2 compound attrition include: the absence of biomarkers to allow compound effects to be consistently tracked through development; a lack of integration/'de-siloing' of the diverse discipline-based and technical skill sets involved in drug discovery; the industrialization of drug discovery, which via volume-based goals often results in quantity being prioritized over quality; inadequate project governance and strategic oversight; and flawed decision making based on unreliable/irreproducible or incomplete data. A variety of initiatives have addressed this problem, including the NIH National Center for Advancing Translational Sciences (NCATS), which has focused on bringing an unbiased academic perspective to translation, to potentially revitalize the process. This commentary provides an overview of the basic concepts involved in translation, along with suggested changes in the conduct of biomedical research to avoid valleys of death, including the use of Translational Scoring as a tool to avoid translational attrition and the impact of the FDA Accelerated Approval Pathway in lowering the hurdle for drug approval. © 2021 Wiley Periodicals LLC.