Everything you need to know about clinical trials

Arunima completed her MSc in Clinical Research from the School of Biosciences, (ASU), Gurgaon. As a Quality Assurance Associate, she audits and ensures the product integrity and that standards are being met. She is also pursuing Ph.D. in Bio and Medical Big data from Gyeongsang National University, South Korea. In an interview, Arunima explains how clinical trials are commonly classified into phases, with each phase having a different objective within the trial. 

What are clinical trials?

Clinical trials are a way to test new methods of diagnosing, treating, or preventing health conditions. The aim is to determine whether a medical strategy, treatment, or device is safe for use or consumption by humans. Clinical trials help improve and advance medical care. The studies provide factual evidence that can be used to improve patient care.

Non-clinical studies

Once a lead drug molecule has been discovered, non-clinical studies are conducted to ensure efficacy and safety. Non-clinical testing is conducted on animals and/or cells or tissues. The main goals of non-clinical studies are to determine a safe dose for first-in-human study and assess potential toxicity of the product. If the pre-clinical research is promising, investigators move forward with a clinical trial to see how well it works in humans.

Phase 1

Clinical trials happen in several phases and each phase must be successfully completed before the next can begin.  The Drugs Controller General of India (DCGI) is an official of the Central Drugs Standard Control Organisation (CDSCO) that is the final regulatory authority for the approval of clinical trials in the country. A Phase I trial tests an experimental treatment on a small group of often healthy people (10 to 20) to judge its safety and side-effects. Investigators conducting research involving human subjects must adhere to good clinical practices (GCPs), including adequate human subject protection (HSP). In India, guidelines related to GCP are issued by the Indian Council of Medical Research. If the results are positive the research data is shared with DCGI who analyse it, and if needed, provide inputs. Once it gives a go-ahead, investigators move to the next phase. For every phase we have to share the results with DCGI.  

Phase 2

A Phase II trial uses more people (50to 100). While the emphasis in Phase I is on safety, the emphasis in Phase II is on effectiveness. The objective is to see how effective the medication is and to gather more information about any side-effects it might cause. This phase can last several years.

Phase 3

A Phase II trial uses 1000 people or more to evaluate how the new medication works in comparison to existing medications for the same condition. The investigators need to prove that the medication is as at least as effective and safe as existing treatment options available in the market.

Phase 4

Phase IV trials are also known as post-marketing surveillance trials that take place after the DCGI has approved the drug use. The efficacy and safety of the drug is monitored in large populations because the side-effects of a drug may not become visible until and unless more people have consumed it over a period of time. The whole process from non-clinical studies to Phase 4 usually takes 7-10 years. For Covid vaccines, this process was expedited as it was an emergency situation.