The drug development process – Part 2 of 3
This is a continuation of the post “The drug development process – Part 1”
Clinical trial development must follow a strict and comprehensive process and there are different objectives and focuses for each phase. Generally, phase I trials assess the toxicity of a drug, while phase II focuses on in-depth study of the drugs activity with the chosen condition or indication. Phase III aims to prove the drugs efficacy (efficiency) as a treatment or cure for a condition. However, the safety of the drug is a common consideration throughout the entire process.
Apart from phase I, where the objective is to examine toxicity, the first requirement for a clinical trial is to develop a concept or question. This is where the ‘clinical endpoint’ is identified as a key element of the study. A clinical endpoint is a health problem, disease, disorder or condition that has the potential to be prevented, treated or cured by the drug being trialed.
Following this, the trial must detail how the study will progress in relation to the trial question or concept. The trial process must adhere to local and regional regulatory requirements, governed by the regulatory authorities. These regulatory authorities oversee pharmaceutical development and ensure that trials are thorough, relevant and above all, safe. They carry out a range of assessment and monitoring activities to ensure pharmaceutical goods are of a high standard. They aim to ensure that access to new and effective treatments is available within a reasonable amount of time.
The Australian regulatory agency, the TGA, sums it up well.
“Although the methods for implementing and enforcing these principles vary across regulatory agencies, the end result, it is hoped, are trials that collect high quality, credible data that contribute to the answering of specific scientific questions, while most importantly protecting the rights, safety and well-being of clinical trial participants.”
Separate from regulatory approval, a study must also gain ethical approval from the relevant ethics committee. These committees can be local to the study site, or governed by region, depending on where the study is taking place. An ethics committee will examine elements such as a trials risk to participants or the accuracy and clarity of information provided to patients in order to obtain their consent.
A trial can only commence once it has received the necessary regulatory and ethical approvals. Usually the next step would be to recruit trial participants. Alongside this, staff and physicians must be trained in the trial protocol, including drug education and how to administer, manage and monitor the trial. Having completed all these steps, the first patient can be dosed.
Traditionally, phase I trials can be completed within months, while phase II trials average two years. A phase III trial is usually longer and more intensive, and these have been known to last up to five years or more.
Interestingly, the approved trial length does not reflect how long the trial will take in real terms. Trial length actually indicates the amount of time a participant is involved in the trial for the study to be considered complete. Not all participants start at the same time, so a 12 month study could take more than two years depending on when the first and last patients begin their dosing.
Following the completion of the each trial there are detailed and rigorous data collection and analysis stages to confirm the trial has answered the research question. Then there is the collating, writing and publication of discoveries, research papers and trial results and conclusions.
Finally, the trial dossier is compiled and submitted to the regulatory body with the goal of receiving approval and proving the case that trials should progress to the next phase of the development process.
This is post 2 of 3 on the drug development process.