COMET-1 is one of two ongoing company-sponsored pivotal trials of cabozantinib in mCRPC. The second trial, COMET-2, is a randomized, double-blind, placebo-controlled phase 3 trial evaluating cabozantinib’s ability to reduce pain associated with bone metastases. COMET-2 continues to enroll patients, and more information on the trial can be found at www.cometclinicaltrials.com or www.clinicaltrials.gov/ct2/show/NCT01522443. Recently initiated phase 3 pivotal trials of cabozantinib in metastatic renal cell carcinoma and advanced hepatocellular carcinoma are also actively recruiting patients.
Cabozantinib inhibits the activity of tyrosine kinases including RET, MET and VEGFR2. These receptor tyrosine kinases are involved in both normal cellular function and in pathologic processes such as oncogenesis, metastasis, tumor angiogenesis, and maintenance of the tumor microenvironment. COMETRIQ® (cabozantinib) is currently approved by the U.S. Food and Drug Administration for the treatment of progressive, metastatic medullary thyroid cancer.
Cobimetinib (GDC-0973/XL518) is a potent, highly selective inhibitor of MEK, a serine/threonine kinase that is a component of the RAS/RAF/MEK/ERK pathway. This pathway mediates signaling downstream of growth factor receptors, and is prominently activated in a wide variety of human tumors. In preclinical studies, oral dosing of cobimetinib results in potent and sustained inhibition of MEK in RAS or B-RAF mutant tumor models, and results in significant tumor regression at well-tolerated doses. Cobimetinib was designed to have low penetration into the brain with the aim of minimizing the potential for the CNS side effects reported with previous MEK inhibitors.
Cobimetinib is being developed by Genentech/Roche under a collaboration agreement with Exelixis. As part of the agreement, Exelixis has the option to co-promote in the United States and will be entitled to receive a share in the profits in the United States. Exelixis will receive royalties on any sales of the product that may be commercialized outside the United States.
COMETRIQ® Important Safety Information, including Boxed Warning
WARNING: PERFORATIONS AND FISTULAS, and HEMORRHAGE
- Serious and sometimes fatal gastrointestinal perforations and fistulas occur in COMETRIQ-treated patients.
- Severe and sometimes fatal hemorrhage occurs in COMETRIQ-treated patients.
- COMETRIQ treatment results in an increase in thrombotic events, such as heart attacks.
- Wound complications have been reported with COMETRIQ.
- COMETRIQ treatment results in an increase in hypertension.
- Osteonecrosis of the jaw has been observed in COMETRIQ-treated patients.
- Palmar-Plantar Erythrodysesthesia (PPE) Syndrome occurs in patients treated with COMETRIQ.
- The kidneys can be adversely affected by COMETRIQ. Proteinuria and nephrotic syndrome have been reported in patients receiving COMETRIQ.
- Reversible Posterior Leukoencephalopathy Syndrome has been observed with COMETRIQ.
- COMETRIQ is not recommended for use in patients with moderate or severe hepatic impairment.
- COMETRIQ can cause fetal harm when administered to a pregnant woman.
Adverse Reactions – The most commonly reported adverse drug reactions (≥25%) are diarrhea, stomatitis, palmar-plantar erythrodysesthesia syndrome (PPES), decreased weight, decreased appetite, nausea, fatigue, oral pain, hair color changes, dysgeusia, hypertension, abdominal pain, and constipation. The most common laboratory abnormalities (≥25%) are increased AST, increased ALT, lymphopenia, increased alkaline phosphatase, hypocalcemia, neutropenia, thrombocytopenia, hypophosphatemia, and hyperbilirubinemia.