A review of therapeutic failures in late-stage clinical trials

INTRODUCTION

The process of drug approval involves extensive and expensive preclinical and clinical examination. Most drugs entering late-stage clinical trials get terminated for a variety of reasons including inability to achieve the primary endpoints or intolerable adverse effects. Only one-tenth of the drugs that enter clinical trials progress to Food and Drug Administration (FDA) regulatory submission.

AREAS COVERED

This review offers insight into some of the attributes that may be responsible for a drug's failure in late-stage trials. Information from multiple open sources including PubMed articles published between 1989 and 2019, recent articles from authentic websites like www.ClinicalTrials.gov, www.fda.gov, and pharmaceutical news articles for the years between 2017 and 2021 were accumulated and summarized. Further, a few drug candidates that reached the phase III clinical trials but were discontinued at later stages have been presented as case studies.

EXPERT OPINION

Ineluctable failures were observed due to insufficient knowledge about the mechanism of action where the disease progression stages are unclear. Other reasons were choice of patient population, late-stage treatment, and dosage. Adhering to the guidelines and recommendations provided by the regulatory authorities and learning from past failures, considerably reduce failure rates.

Assessment of the breakthrough-therapy-designated drugs granted in China: A pooled analysis 2020-2022

The implementation of China's breakthrough therapy designation (BTD) program in 2020 to accelerate drug development for serious or life-threatening diseases has attracted widespread attention. Here, we review the characteristics of BTD and its implementation in China. Overall, 78 drugs with 82 BTDs were collected from the program's inception to April 2022. The time to obtain BTD for imported new drugs was significantly faster than for domestic ones. The BTDs granted for domestic new drugs were highly concentrated in oncology. The BTD drugs can reduce clinical trial and review times compared with non-BTD drugs. The implementation of BTD is expected to expedite the development of new drugs to address unmet clinical needs in China.

The drug lag and associated factors for orphan anticancer drugs in Japan compared to the United States

The approval of orphan anticancer drugs in Japan has increased to meet high social demand. Drug lag, namely the approval lag of new drugs, is recognized as a social issue in Japan. We investigated the approval lag and its components, submission lag and review-time lag, between Japan and the United States (US) to reveal whether an approval lag still exists, and to identify potential factors that may contribute to reducing the approval lag. Anticancer drugs approved in Japan between April 2004 and November 2017 were investigated using publicly available information. Results showed that the median approval lag of orphan anticancer drugs in 2016-2017 was 727.0 days (interquartile range, IQR, 310.0-1054.3). The approval lag was significantly correlated with the submission lag (correlation coefficient = 1.00, P < 0.001) but not with the review-time lag (correlation coefficient = -0.16, P = 0.22). The submission lag was significantly longer for orphan anticancer drugs than non-orphan drugs (median, 712.5 days [IQR, 186.0-1448.3] vs. 387.0 days [92.8-1096.0], P = 0.023). External collaboration in drug development was associated with a longer submission lag (coefficient = 762.1, P = 0.017), while breakthrough therapy designation in the US was associated with a shorter submission lag (coefficient = -832.8, P = 0.035). In conclusion, we revealed that an approval lag for orphan anticancer drugs still existed in 2016-2017. A submission lag for orphan anticancer drugs was the main component affecting the approval lag, and was longer than that for non-orphan drugs. External collaboration in drug development may be a potential factor in reducing the submission lag for orphan anticancer drugs.