Exelixis Announces First Patient Enrolled in Phase 1 Trial Cohort Evaluating XL092 in Combination with Atezolizumab in Patients with Advanced Solid Tumors

– Promising findings featuring XL092, Exelixis’ next-generation oral tyrosine kinase inhibitor, recently presented at the 32nd EORTC-NCI-AACR (ENA) Symposium –

ALAMEDA, Calif.--(BUSINESS WIRE)-- Exelixis, Inc. (NASDAQ: EXEL) today announced enrollment of the first patient into the dose-escalation cohort of the combination arm of the phase 1 trial (NCT03845166) evaluating the safety, tolerability, pharmacokinetics and preliminary anti-tumor activity of XL092 alone and in combination with atezolizumab (TECENTRIQ®) in patients with advanced solid tumors. XL092 is an investigational, next-generation oral tyrosine kinase inhibitor that targets VEGF receptors, MET, AXL, MER and other kinases implicated in the growth and spread of cancer.

“This exciting update follows promising preclinical findings presented at the ENA Symposium suggesting that XL092, like cabozantinib, promotes an immune-permissive environment that may result in synergies with immune checkpoint inhibitors; however, as seen in the ongoing phase 1 study, XL092 has a much shorter pharmacokinetic half-life that may help physicians in managing tolerability,” said Gisela Schwab, M.D., President, Product Development and Medical Affairs and Chief Medical Officer, Exelixis. “Enrolling the first patient into the combination therapy part of this trial is an important step forward in the development of XL092 as we explore how it may improve outcomes for patients with difficult-to-treat cancers and build on the success of our cabozantinib oncology franchise.”

Initiated in February 2019, the dose-escalation evaluation of the XL092 monotherapy arm of the phase 1 trial is ongoing. Once the recommended doses of both single-agent XL092 and XL092 in combination with atezolizumab are established, the trial will begin to enroll expansion cohorts for patients with clear cell and non-clear cell renal cell carcinoma, hormone-receptor positive breast cancer and metastatic castration-resistant prostate cancer.

More information about this trial is available at ClinicalTrials.gov.

About XL092

XL092 is a next-generation oral tyrosine kinase inhibitor that targets VEGF receptors, MET, AXL, MER and other kinases implicated in cancer’s growth and spread. In designing XL092, Exelixis sought to build upon the experience and target profile of cabozantinib, the company’s flagship medicine, while improving key characteristics, including clinical half-life. XL092 is the first internally discovered Exelixis compound to enter the clinic following the company’s reinitiation of drug discovery activities.

About CABOMETYX® (cabozantinib)

In the U.S., CABOMETYX tablets are approved for the treatment of patients with advanced RCC and for the treatment of patients with HCC who have been previously treated with sorafenib. CABOMETYX tablets have also received regulatory approvals in the European Union, Japan 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 United States and Japan. In 2017, Exelixis granted exclusive rights to Takeda Pharmaceutical Company Limited 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 United States.

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 and HCC studies. Discontinue CABOMETYX for Grade 3 or 4 hemorrhage. Do not administer CABOMETYX to patients who have a recent history of hemorrhage, including hemoptysis, hematemesis, or melena.

Perforations and Fistulas: Gastrointestinal (GI) perforations, including fatal cases, occurred in 1% of CABOMETYX patients. Fistulas, including fatal cases, occurred in 1% of CABOMETYX patients. Monitor patients for signs and symptoms of perforations and fistulas, 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 event requiring medical intervention.

Hypertension and Hypertensive Crisis: CABOMETYX can cause hypertension, including hypertensive crisis. Hypertension occurred in 36% (17% Grade 3 and