RE:In today's world the paths to FDA Approval are many Clinical trials in oncology have terminology, including primary endpoints and surrogate endpoints, which are results that are measured at certain points during a study and/or at the completion of a study to see if a given medication has worked (e.g., did the drug demonstrate a significant improvement versus the comparative treatment?) and its safety (e.g., what are the possible side effects?). The U.S. Food and Drug Administration (FDA) uses study endpoints to inform drug approval decisions, while patients and physicians use endpoints to inform treatment decisions.
Overall Response Rate (ORR)
Overall response rate, or ORR, is the proportion of patients in a trial whose tumor is destroyed or significantly reduced by a drug. Improved ORR offers tangible proof that the drug is working. ORR anticipates PFS response.
Progression-Free Survival (PFS)
Another important endpoint for measuring the effectiveness of cancer drugs is progression-free survival, or PFS – how long a person lives without the disease worsening. PFS results are typically available earlier in a trial than OS data. PFS is considered an indication of disease control and stabilization. PFS anticipates OS.
Duration of Response (DoR)
Duration of response, or DoR, is the length of time that a tumor continues to respond to treatment without the cancer growing or spreading. Cancer drugs that demonstrate improved DoR can produce a durable, meaningful delay in disease progression, as opposed to a temporary response without any lasting benefit.
Overall Survival (OS)
Overall survival, or OS, measures how long patients, who undergo a certain treatment regimen, live compared to patients who are in a control group (i.e., taking either another drug or an inactive treatment, known as a placebo). If a clinical trial demonstrates improved OS, it provides evidence of the drug’s value in prolonging a cancer patient’s life. OS is a strong and precise endpoint, as it requires having more patients and longer follow-ups compared to other clinical trial endpoints. Given all this, OS is often considered the “gold standard” for measuring the clinical benefits of a cancer drug.