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What is a Clinical Research Organization?

Clinical Research Organization (CRO) is a company contracted by a pharmaceutical, biological or medical device manufacturer to manage clinical research studies and other services to support product development. There are four phases of clinical trials:

The four phases of clinical trials

Phase I

  • Establishes the effect of a new drug in humans
  • Usually conducted on small (12-50) populations of healthy volunteers and/or patients
  • Determines a drug's toxicity, absorption, distribution, metabolism and excretion

Phase II

  • Tests a drug for safety and efficacy in a relatively small (200-500) population of patients
  • Patients are afflicted with the disease or condition for which the drug is being developed

Phase III

  • Tests the drug in relatively large populations of patients (500-5,000 or more)
  • Usually compares the new drug to placebo or to the standard therapy currently being used for the disease of interest
  • Results usually provide package insert info (Prescribing Information for doctors, and Patient Information materials)

Phase IV

  • Conducted after a drug has been approved by a Regulatory Authority
  • Compares the drug to competitor drugs, to explore additional patient populations or disease indications, or to further assess the safety of the drug

Key Functions of CROs

CROs serve as an important component of the drug development ecosystem, offering a wide range of services that encompass every phase of the clinical trial process. Some of the key functions of CROs include:

    1. Protocol design and development: CROs assist sponsors in creating robust and scientifically sound study protocols that define the scope, objectives, and methodologies of the clinical trial.

    2. Patient recruitment and retention: CROs employ various strategies to identify and enroll eligible patients for clinical trials, ensuring that participant targets are met. They also focus on patient retention through engagement and support.

    3. Regulatory and ethics compliance: CROs navigate complex regulatory requirements and ensure adherence to ethical considerations, protecting the rights and well-being of study participants.

    4. Clinical trial operation: CROs manage the day-to-day operations of clinical trials, including site selection, monitoring, data collection, and adverse event reporting, among other activities.

    5. Data management and biostatistics: CROs employ advanced technologies and robust data management systems to collect, scrutinize, and analyze trial data, generating high-quality evidence to support regulatory submissions.

    6. Quality assurance and control: CROs implement comprehensive quality assurance measures to ensure that clinical trials are conducted in accordance with Good Clinical Practice (GCP) guidelines, industry standards, and regulatory requirements.

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