New Clinical Research Program Initiated for the Prevention and Treatment of Life-Threatening Blood Clots in Patients with Cancer

In In The News by Barbara Jacoby

Janssen Pharmaceuticals, Inc. (Janssen) and its development partner, Bayer HealthCare, today announced the initiation of CALLISTO, a new comprehensive clinical research program for their novel oral anticoagulant, rivaroxaban, in patients with active cancer. The studies are evaluating the medicine for the prevention and treatment of life-threatening blood clots in patients with a wide range of cancer types.

In patients with cancer, the risk of venous thromboembolism (VTE), which is a blood clot in the deep veins or the lungs, is up to five times higher compared to people the same age without cancer, and the risk magnifies in those receiving chemotherapy. The occurrence of VTE may also cause delays in patients receiving critical treatment for their cancer, including surgery or chemotherapy. Blood clots are the second leading cause of death in patients with cancer and preventing their occurrence represents a significant unmet need for patients and their providers.

“Not only are blood clots more severe and widespread in the body of patients with cancer, but their development is also linked to the management of cancer,” said Gerald A. Soff, MD, Chief, Hematology Service, Memorial Sloan Kettering Cancer Center, New York, NY, and a principal investigator in CALLISTO. “Though blood clots are largely preventable, current therapy is only approved for the treatment of these clots after they’ve formed, or to prevent clots in patients who are hospitalized. This means a large number of the one million patients who are treating their cancer outside the hospital each year are at risk of developing blood clots, and reducing their incidence is a high priority in cancer care.” Dr. Soff is compensated by Janssen Pharmaceuticals, Inc., for his role as a principal investigator in the clinical research program.

Known as CALLISTO, the new oncology research program is part of Janssen and Bayer HealthCare’s broader EXPLORER clinical development program, evaluating patient populations being treated for blood clots or at high risk for developing them. The CALLISTO program will encompass the field of cancer-associated thrombosis (blood clots) through nine studies, including seven clinical trials and two registries across various cancer types, in more than 4,000 patients globally.

The advisory council for the program will be chaired by Alok A. Khorana, MD, FACP, Sondra and Stephen Hardis Chair in Oncology, Vice Chair for Clinical Services, Director of the GI Malignancies Program, Taussig Cancer Institute Cleveland Clinic, Cleveland, OH.

“Cancer-associated thrombosis is a highly prevalent complication of cancer treatments, including chemotherapy, targeted therapy and small molecules. Occurrence of clots can disrupt patient quality of life, affect delivery of cancer treatments and increase the number of hospitalizations and use of healthcare resources,” said Dr. Khorana. “Although it may be largely preventable, focused studies in the cancer population using newer, more patient-friendly agents have not yet been conducted. This planned program that will engage cancer researchers nationwide seeks to address this unmet need of cancer patients, and the prevention and treatment of cancer-associated thrombosis.” Dr. Khorana is compensated by Janssen Pharmaceuticals, Inc., for his role as chair of the CALLISTO advisory council and co-chair of the VTE prevention study steering committee.

The research will evaluate rivaroxaban in the following studies:

  • Prevention of VTE. A prospective, randomized, double-blind, placebo-controlled trial for the primary prevention of blood clots in adult patients with active cancer who are scheduled to receive therapy to control, slow or eradicate the cancer, such as chemotherapy, in the outpatient setting. Endpoints include incidence of VTE and major bleeding events. The trial will enroll patients at high risk of developing blood clots based on their modified Khorana risk score (a recognized scoring system for predicting blood clots in patients with cancer), and will study patients with solid cancers, including but not limited to the pancreas, lung, stomach, colon, rectum, bladder, breast, kidney and ovary, and those with lymphoma. As one-third of all VTE events are “silent,” or asymptomatic, the study will follow patients over a six-month period and use periodic medical imaging to evaluate the occurrence of “silent” clot formation, which will help identify when these events are happening.
  • Treatment of VTE.
    • Three studies comparing rivaroxaban to the low-molecular-weight heparin (LMWH) dalteparin, the current standard of care, for the treatment of blood clots in patients with active cancer. Endpoints include incidence of recurrent events and major bleeding. The studies will enroll patients with various cancer types, and will include two randomized studies and one quality of care improvement analysis.
    • Two observational registries, one in the U.S. and one outside the U.S., will follow various outcomes of cancer patients with blood clots who are treated with an anticoagulant to better understand the treatment of VTE and the prevention of recurrent events in this patient population. A sub-study will assess the treatment of blood clots specifically in patients with cancer who must undergo surgical procedures.
  • Relevant Clinical Aspects. Three additional studies will focus on important clinical aspects, such as concomitant use of rivaroxaban with standard cancer therapies, like chemotherapy, and assessment of a bridging strategy for patients taking rivaroxaban or LMWH in instances where chemotherapy-induced vomiting makes oral therapies challenging.

“CALLISTO is unlike any other initiative for cancer-associated blood clots in its scope, size and ambition,” said Paul Burton, MD, PhD, Vice President, Medical Affairs, Janssen. “The program will harness our deep experience in oncology and thrombosis so that we can better assess how to reduce the burden of blood clots in patients with cancer, while also improving our understanding of how rivaroxaban may be used in the context of complex cancer treatment strategies.

“Through CALLISTO, part of our broader EXPLORER program which includes six additional indication-seeking studies underway in collaboration with Bayer HealthCare, we are striving to uncover the full potential of our medicine in making a difference for patients with critical medical needs,” he continued.

The EXPLORER program is evaluating patients with chronic heart failure, coronary artery disease, peripheral artery disease, acute coronary syndrome, embolic stroke of undetermined source and now, active cancer. By the time of its completion, more than 275,000 patients will have participated in the clinical development program, other completed and ongoing clinical trials, investigative registries, and non-interventional studies.

Janssen in Oncology

In oncology, our goal is to fundamentally alter the way cancer is understood, diagnosed and managed, reinforcing our commitment to the patients who inspire us. In looking to find innovative ways to address the cancer challenge, our primary efforts focus on several treatment and prevention solutions. These include a focus on hematologic malignancies, prostate cancer and lung cancer; cancer interception with the goal of developing products that interrupt the carcinogenic process; biomarkers that may help guide targeted, individualized use of our therapies; as well as safe and eff