Analysis of Regulatory Botanical Submission Profile for Cancer Management from the U.S. FDA Perspectives

The United States Food and Drug Administration (FDA) has received over 700 botanical investigational new drug applications (INDs) in a broad spectrum of therapeutic areas since 1984. The greatest numbers were for cancer management. The aims of our study were to conduct a first-time, in-depth analysis of the regulatory submission profiles for botanical INDs with oncologic indications, in comparison with non-oncologic indications, and to share our regulatory review experience of oncologic botanical drug research and development.

The FDA Center for Drug Evaluation and Research (CDER) maintains an in-house database of botanical INDs that contains many data elements, including initial 30-day actions (safe-to-proceed, clinical hold, etc.), current regulatory status, primary purpose of the proposed clinical trials, and initially proposed clinical trial phase information by sponsor. The database provided internally validated regulatory submission information that FDA received between March 1984 and December 2020 for 254 botanical INDs with oncologic indications, as well as 485 non-oncologic botanical INDs.

A higher percentage of the oncologic botanical INDs (69% versus 58% for non-oncologic botanical INDs, p < 0.01) received an initial 30-day safe-to-proceed designation to initiate the clinical investigations. One hundred thirty-seven oncologic botanical INDs were submitted to conduct phase 1 trials to investigate the safety and tolerability of their products, and 46 of these INDs are currently active. An additional 117 INDs were proposed to conduct phase 2 or phase 3 trials to assess safety and efficacy of oncologic botanical products, and 36 of those INDs are currently active, including 3 INDs in phase 3 trials. Most of the oncologic botanical INDs were for the investigation of specific solid tumors (71%) with more than one third of these related to prostate and breast tumors.

Despite the scientific and regulatory challenges that FDA reviewers previously experienced, our analysis shows that there were over 80 currently active botanical oncologic INDs, including several in the late phase of drug development for cancer management. The implication of this finding is significant in that many clinical trials of botanical drug products intended to provide high-quality cancer patient care are in the regulatory pipeline.