– STELLAR-303 is the first phase 3 pivotal trial evaluating XL092, a next-generation oral tyrosine kinase inhibitor –
ALAMEDA, Calif.--(BUSINESS WIRE)-- Exelixis, Inc. (Nasdaq: EXEL) today announced the initiation of STELLAR-303, a phase 3 pivotal trial evaluating XL092 in combination with atezolizumab versus regorafenib in patients with metastatic colorectal cancer (CRC) that is not microsatellite instability-high or mismatch repair-deficient, who have progressed after or are intolerant to the standard of care therapy. XL092 is a next-generation tyrosine kinase inhibitor (TKI) in development for multiple advanced tumor types.
“There is a significant need for new treatment options for the majority of metastatic CRC patients, who do not have microsatellite instability-high or mismatch-repair deficient disease and whose tumors do not respond to immunotherapy alone,” said Vicki L. Goodman, M.D., Executive Vice President, Product Development & Medical Affairs, and Chief Medical Officer, Exelixis. “Following recent promising data evaluating cabozantinib in combination with immunotherapies in colorectal cancer, we are thrilled to initiate our first phase 3 pivotal trial for XL092, our next-generation tyrosine kinase inhibitor. We look forward to learning more about how XL092 in combination with atezolizumab may benefit patients with metastatic colorectal cancer.”
STELLAR-303 is a global, multicenter, randomized phase 3 open-label study that will enroll approximately 600 patients with documented RAS status. Patients will be randomized 1:1 to receive either XL092 in combination with atezolizumab or regorafenib. The primary objective of the study is to evaluate the efficacy of the combination in patients with RAS wild-type disease; exploratory endpoints include examining efficacy in those with RAS-mutated disease. The primary endpoint is overall survival. Secondary endpoints include progression-free survival, objective response rate and duration of response per Response Evaluation Criteria in Solid Tumors version 1.1 as assessed by the investigator.
Previously announced results from two studies of cabozantinib in combination with immunotherapies for the treatment of advanced CRC supported Exelixis’ decision to pursue clinical development of XL092 in this setting. The trial is sponsored by Exelixis, and Roche is supplying atezolizumab.
About XL092
XL092 is a next-generation oral TKI that inhibits the activity of receptor tyrosine kinases implicated in cancer growth and spread, including VEGF receptors, MET, AXL and MER. These receptor tyrosine kinases are involved in both normal cellular function and in pathologic processes such as oncogenesis, metastasis, tumor angiogenesis and resistance to multiple therapies, including immune checkpoint inhibitors. In designing XL092, Exelixis sought to build upon its extensive experience with and the target profile of cabozantinib, the company’s flagship medicine, while improving key characteristics, including pharmacokinetic half-life. XL092 is currently being developed for the treatment of advanced solid tumors, including genitourinary cancers, as a monotherapy and in combination with immune checkpoint inhibitors. XL092 is the first internally discovered Exelixis compound to enter the clinic following the company’s reinitiation of drug-discovery activities.
About Colorectal Cancer
Colorectal cancer is the third most common cancer and the third-leading cause of cancer-related deaths in the U.S. According to the American Cancer Society, about 150,000 new cases will be diagnosed and 53,000 people will die from the disease in 2022.1 Colorectal cancer is most frequently diagnosed among people aged 65-74 and is more common in men and those of African American descent. Nearly a quarter of colorectal cancer cases are diagnosed at the metastatic stage, at which point the five-year survival rate is just 15%.2 It has been estimated that approximately 40% of metastatic colorectal cancer cases exhibit a RAS mutation.3
About CABOMETYX® (cabozantinib)
In the U.S., CABOMETYX tablets are approved for the treatment of patients with advanced renal cell carcinoma (RCC); for the treatment of patients with hepatocellular carcinoma (HCC) who have been previously treated with sorafenib; for patients with advanced RCC as a first-line treatment in combination with nivolumab; and for adult and pediatric patients 12 years of age and older with locally advanced or metastatic differentiated thyroid cancer (DTC) that has progressed following prior VEGFR-targeted therapy and who are radioactive iodine-refractory or ineligible. CABOMETYX tablets have also received regulatory approvals in the European Union and additional countries and regions worldwide. In 2016, Exelixis granted Ipsen exclusive rights for the commercialization and further clinical development of cabozantinib outside of the U.S. and Japan. In 2017, Exelixis granted exclusive rights to Takeda for the commercialization and further clinical development of cabozantinib for all future indications in Japan. Exelixis holds the exclusive rights to develop and commercialize cabozantinib in the U.S.
CABOMETYX is not indicated as a treatment for metastatic colorectal cancer CRC that is not microsatellite instability-high or mismatch repair-deficient.
IMPORTANT SAFETY INFORMATION
WARNINGS AND PRECAUTIONS
Hemorrhage: Severe and fatal hemorrhages occurred with CABOMETYX. The incidence of Grade 3 to 5 hemorrhagic events was 5% in CABOMETYX patients in RCC, HCC, and DTC studies. Discontinue CABOMETYX for Grade 3 or 4 hemorrhage and prior to surgery as recommended. Do not administer CABOMETYX to patients who have a recent history of hemorrhage, including hemoptysis, hematemesis, or melena.
Perforations and Fistulas: Fistulas, including fatal cases, occurred in 1% of CABOMETYX patients. Gastrointestinal (GI) perforations, including fatal cases, occurred in 1% of CABOMETYX patients. Monitor patients for signs and symptoms of fistulas and perforations, including abscess and sepsis. Discontinue CABOMETYX in patients who experience a Grade 4 fistula or a GI perforation.
Thrombotic Events: CABOMETYX increased the risk of thrombotic events. Venous thromboembolism occurred in 7% (including 4% pulmonary embolism) and arterial thromboembolism in 2% of CABOMETYX patients. Fatal thrombotic events occurred in CABOMETYX patients. Discontinue CABOMETYX in patients who develop an acute myocardial infarction or serious arterial or venous thromboembolic events that require medical intervention.
Hypertension and Hypertensive Crisis: CABOMETYX can cause hypertension, including hypertensive crisis. Hypertension was reported in 37% (16% Grade 3 and 3 times ULN (Grade ≥2) was reported in 83 patients, of whom 23 (28%) received systemic corticosteroids; ALT or AST resolved to Grades 0-1 in 74 (89%). Among the 44 patients with Grade ≥2 increased ALT or AST who were rechallenged with either CABOMETYX (n=9) or nivolumab (n=11) as a single agent or with both (n=24), recurrence of Grade ≥2 increased ALT or AST was observed in 2 patients receiving CABOMETYX, 2 patients receiving nivolumab, and 7 patients receiving both CABOMETYX and nivolumab. Withhold and resume at a reduced dose based on severity.
Adrenal Insufficiency: CABOMETYX in combination with nivolumab can cause primary or secondary adrenal insufficiency. For Grade 2 or higher adrenal insufficiency, initiate symptomatic treatment, including hormone replacement as clinically indicated. Withhold CABOMETYX and/or nivolumab and resume CABOMETYX at a reduced dose depending on severity.
Adrenal insufficiency occurred in 4.7% (15/320) of patients with RCC who received CABOMETYX with nivolumab, including Grade 3 (2.2%), and Grade 2 (1.9%) adverse reactions. Adrenal insufficiency led to permanent discontinuation of CABOMETYX and nivolumab in 0.9% and withholding of CABOMETYX and nivolumab in 2.8% of patients with RCC.
Approximately 80% (12/15) of patients with adrenal insufficiency received hormone replacement therapy, including systemic corticosteroids. Adrenal insufficiency resolved in 27% (n=4) of the 15 patients. Of the 9 patients in whom CABOMETYX with nivolumab was withheld for adrenal insufficiency, 6 reinstated treatment after symptom improvement; of these, all (n=6) received hormone replacement therapy and 2 had recurrence of adrenal insufficiency.
Proteinuria: Proteinuria was observed in 8% of CABOMETYX patients. Monitor urine protein regularly during CABOMETYX treatment. For Grade 2 or 3 proteinuria, withhold CABOMETYX until improvement to ≤ Grade 1 proteinuria, resume CABOMETYX at a reduced dose. Discontinue CABOMETYX in patients who develop nephrotic syndrome.
Osteonecrosis of the Jaw (ONJ): ONJ occurred in

