You are using an unsupported browser.
Some features of this site may not function properly. For optimal user experience, please view this site in Chrome, Firefox, Safari, or Edge.



We put science for patients first when developing transformative therapies, and Carestone, our family of clinical studies, is designed around populations with an unmet need in oncology. 

Carestone logo

Carestone Clinical Studies help ensure that patients receive viable options—even if the standard of care may evolve during the study, we have introduced design elements that will ensure study participants continue to receive standard of care while we maintain the integrity of the study. 

TESARO conducts bold and scientifically rigorous research in order to answer the difficult clinically relevant research questions that will improve treatment options for people impacted by cancer to work towards our goal of ensuring that no patient is left behind.

With this in mind, TESARO takes the time to learn from people in the cancer community, including treating physicians, medical associations, advocates, and patients themselves. This crucial input before, during, and after a study has led to practical improvements in how we design and carry out our Carestone Clinical Studies so that they are not overly burdensome to study volunteers.



Researchers are always looking for ways to improve upon and develop new treatments for people impacted by cancer. Clinical studies are conducted to evaluate how safe and effective potential treatments are and how well they work. Clinical studies often provide an opportunity to get early access to promising therapies and can be considered an integral part of your treatment plan, not just a "last resort.”

Phases of Clinical Studies


Identify and validate therapeutic targets, and perform characterization assays to assess the potential for treatment indications for clinical trial investigations.


In vitro and in vivo experiments are conducted to obtain preliminary efficacy, toxicity, and pharmacokinetic results. 

Phase 1

The new drug or treatment is tested in a small group of people for the first time to evaluate its safety, including determining the appropriate dose and identifying side effects.

Phase 2

The drug or treatment is further evaluated for its safety and the effect it has on the cancer that is being targeted in a larger group of people.

Phase 3

Researchers evaluate the drug or treatment to confirm its effectiveness in large groups of people, monitor side effects, and compare it with the standard treatment.

Phase 4

After a drug or treatment has been approved and available to patients, phase 4 studies are conducted to look at the long-term safety and effectiveness of a treatment.


Every clinical study starts with a protocol that is a detailed description for the study doctor of exactly how the study should be conducted. It includes defined criteria for eligibility (inclusion and exclusion criteria) and allows the healthcare team to know exactly what procedures must be done at specific time points throughout the study. Every doctor who conducts the clinical study, no matter where they are located globally, conducts it in exactly the same way. 

Participating in a clinical study has the potential to positively impact thousands of lives. All of us at TESARO are dedicated to improving the lives of people living with cancer by developing effective and safe medicines. The clinical studies described on this site will advance our understanding of how certain cancers respond to different treatments. We thank you for taking the time to get to know our unique approach to cancer care through the information presented here.