Clinical Trials

Enrollment in one of our clinical trials is our primary method for providing patients with access to our investigational drugs prior to their potential approval by regulatory authorities, including the United States Food and Drug Administration, and subsequent commercial availability. Clinical trials are required to demonstrate that an investigational drug meets safety and efficacy standards necessary for approval by regulatory authorities.

To participate in one of our clinical trials, you and your disease must meet specific criteria. As participation in a clinical trial comes with risks, you must also provide your “informed consent” prior to enrolling in a clinical trial.

Our goal is to ensure that appropriate patients can access our investigational drugs at the appropriate time and in the correct manner. We encourage participation in clinical trials and believe that participating in a clinical trial is the best way for patients to access our investigational drugs prior to regulatory approval.

Learn more about clinical trials

Expanded Access

Expanded access refers to a situation where a patient with a serious condition who has exhausted all available treatment options, and an ongoing clinical trial is not an option, receives approval to use an investigational drug outside of a clinical trial.

We welcome requests for expanded access from physicians treating patients with the diseases that our investigational drugs are intended to treat, and we take great care to have each individual patient case assessed by a physician on our staff. However, it is important to remember that investigational drugs have not yet received regulatory approval and that their potential risks and benefits are therefore not yet established. Doctors and patients should consider all possible benefits and risks when seeking expanded access to an unapproved investigational drug.

We consider a number of factors consistent with the FDA and other regulatory agencies’ guidelines when considering whether to grant expanded access with respect to our investigational drugs. These factors include:

  • The illness must be serious or life-threatening with no other viable treatment options such as approved products or active clinical trials.
  • There must be sufficient evidence that the potential benefit to the patient would likely outweigh the potential risks, based on currently available safety and efficacy information for the investigational drug.
  • We must have the ability to provide the investigational drug in a fair and equitable manner so that there is adequate manufacturing capacity for our ongoing clinical trials and other existing patients.
  • Granting expanded access may not in any way compromise the scientific validity of Five Prime’s broader development programs or interfere with or delay current clinical trials or regulatory filings, which are designed to make the investigational drug available to many more patients.

Decisions about granting expanded access to our investigational products are made after considerable thought. Our first concern is the safety and well-being of patients. At this time, we believe that participation in one of our clinical trials is the most appropriate way to access our investigational drugs. If you have questions or would like more information about enrolling in one of our clinical trials, please contact us at We anticipate acknowledging receipt of requests sent to this email address within five business days.

In line with the 21st Century Cures Act, we may revise this policy at any time without notice. To the extent we allow expanded access to any of our investigational drugs, this website and policy will be updated with a hyperlink or other reference to the expanded access record on after such record becomes active.