Phases of Clinical Research : An Overview


Before delving into clinical trials, it’s crucial to understand that while preclinical research lays the foundation by answering basic questions about a drug’s safety, clinical research takes the investigation further by examining how the drug interacts with the human body. The development of new drugs and therapies involves a meticulous process called clinical trials. These trials are conducted in stages, with each phase serving a specific purpose. There are four main phases: Phase I, Phase II, Phase III, and Phase IV. This phased approach ensures the safety and efficacy of new treatments before they become widely available.

Designing Clinical Trials:
Clinical trials are meticulously designed to address specific research questions pertaining to a medical product. These trials adhere to a predefined study plan, known as a protocol, developed by researchers or manufacturers. Before commencement, researchers meticulously review prior information about the drug, outline research questions and objectives, determine participant eligibility criteria, specify the study duration, address research bias, establish dosage regimens, delineate assessment protocols, and outline data analysis methodologies.

Phases of Clinical Trials:

Source: National Cancer Institute (NIH)

Phase 1:

  • Objective: Safety and Dosage 
  • Participants: 20 to 100 healthy volunteers or individuals with the targeted disease/condition 
  • Duration: Several months

Phase I trials, aimed at assessing safety, side effects, and dosage, are typically conducted on a small cohort of participants. These trials initiate with low-dose administration of the investigational treatment, with dosage adjustments made based on observed side effects and pharmacological responses. The primary goals include determining treatment safety, identifying potential side effects, and evaluating drug metabolism within the body. Approximately 70% of drugs progress to the subsequent phase following Phase I trials.

Phase 2:

  • Objective: Efficacy and Side Effects 
  • Participants: Up to several hundred individuals with the targeted disease/condition 
  • Duration: Several months to 2 years

Phase II trials delve deeper into assessing treatment efficacy, safety, and dosage in a larger participant pool. These trials aim to ascertain treatment safety, efficacy, optimal dosage regimens, and comparative effectiveness against existing therapies. Approximately 33% of drugs advance to Phase III trials following Phase II assessments.

Phase 3:

  • Objective: Efficacy and Adverse Reaction Monitoring 
  • Participants: 300 to 3,000 volunteers with the targeted disease or condition 
  • Duration: 1 to 4 years

Phase III trials, conducted on a larger participant sample, meticulously evaluate treatment effectiveness, safety, and adverse reactions. By comparing treatment outcomes against standard therapies and assessing dosing variations, researchers gather robust evidence to support treatment efficacy and safety. Approximately 25-30% of drugs progress to Phase IV trials following Phase III assessments.

Phase 4: Post-market Surveillance Objective: Safety and Efficacy

Phase IV trials, also known as post-marketing or therapeutic use studies, are conducted on approved drugs to monitor safety and efficacy in real-world settings. These trials investigate rare but serious side effects that may emerge once the treatment is widely used. Researchers observe treatment outcomes across diverse patient populations, dosage regimens, and treatment combinations to ensure ongoing risk assessment and management.

Clinical research, spanning different phases from safety evaluations to post-market surveillance, incorporates a meticulous and systematic approach to drug development. By adhering to rigorous protocols and prioritizing participant safety, clinical trials serve as the cornerstone of medical innovation, paving the way for safer and more effective treatments that enhance global healthcare outcomes.

Lambda Therapeutic Research

Lambda Therapeutic Research stands at the forefront of the global Clinical Research Organization (CRO) landscape, headquartered in Ahmedabad, India, and extending its impact across Mehsana (India), Warsaw (Poland), London (UK), Toronto (Canada), Pittsburgh (USA), and Las Vegas (USA).

Our unwavering mission revolves around providing comprehensive end-to-end clinical research services to the global innovator, biotech, and generic pharmaceutical industries. Lambda has consistently raised the bar in the Clinical Research sector, achieving milestones through both organic growth and strategic acquisitions. In 2019, we strategically bolstered our North American presence by acquiring Novum Pharmaceutical Research Services, a distinguished 50-year-old CRO. Operating under the unified brand of Novum Pharmaceutical Research Services in North America, Lambda reinforces its position as a key player in the global CRO market.

Prioritizing secure IT infrastructure and automation, Lambda ensures timely project delivery, adhering to global regulatory standards. Our outstanding regulatory track record is underscored by over 60 successful international inspections and audits conducted by esteemed authorities, including the USFDA, EMEA, MHRA, EU member states, and other global bodies over the past five years.

Lambda’s dedication to excellence has garnered widespread recognition, with accolades such as the distinction of ‘Best Indian CRO’ by Frost & Sullivan (USA) and the prestigious title of ‘Great Indian Workplace’ by UBS Transformance. In the latest achievements, Lambda Therapeutic Research proudly received the ‘Regulatory Excellence’ Award at the CPhI Awards 2023 and the ‘Industry Partner of the Year’ Award at the Global Generics & Biosimilar Awards 2023. These honors reflect our ongoing commitment to regulatory compliance, industry leadership, and impactful collaborations within the pharmaceutical and clinical research sectors.

Learn more about why Lambda is trusted partner by biotech pharma.

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