|Exelixis Announces Updated Phase 1 Trial Results for Cabozantinib in Combination with Nivolumab with or without Ipilimumab in Refractory Genitourinary (GU) Tumors|
– Results among 19 previously treated metastatic urothelial carcinoma (mUC) patients demonstrated a 42% objective response rate (ORR), 12.8 month median progression-free survival (mPFS), and 77% overall survival (OS) at 12 months, with 7/8 responders progression free with 15.7 months median follow-up –
– In the cohort of 13 previously treated metastatic renal cell carcinoma (mRCC) patients, a 54% ORR and 100% disease control rate (DCR) was observed –
– These initial results suggest that further evaluation of cabozantinib in combination with nivolumab with or without ipilimumab is warranted for mUC –
The updated data reported results from 78 patients treated with cabozantinib and nivolumab with or without ipilimumab. The initial part of the study determined the recommended dose for each treatment at four dose levels. In all, 49 patients were treated with the doublet combination of cabozantinib and nivolumab and 29 patients were treated with the triplet combination of cabozantinib, nivolumab and ipilimumab. Nineteen patients with mUC were evaluable for response with a median follow up of 15.7 months. Thirteen patients with previously treated mRCC were evaluable for response.
For the mUC cohort, the ORR across all treatment groups was 42 percent (2 CRs and 6 PRs of 19 patients) and the DCR (DCR = CR, PR and SD) was 84 percent. Seven of eight (88 percent) mUC patients with an objective response had not progressed at the time of the data cut-off. Median PFS in this patient population was 12.8 months and the overall survival rate at 12 months was 77 percent. Among the 13 patients with mRCC who were evaluable for response, ORR was 54 percent (7 PRs of 13 patients) and the DCR was 100 percent.
In the overall study, the ORR in 64 evaluable patients was 36 percent (3 CRs and 20 PRs) with a median duration of response (DOR) of 24 months. 78 patients were included in the safety analysis. Expected immune-related events including colitis, meningitis, hepatitis, pneumonitis and endocrine disorders occurred at a low frequency.
“The updated analysis of this trial shows that cabozantinib, in
combination with nivolumab or in combination with nivolumab plus
ipilimumab, demonstrates an acceptable tolerability profile and
encouraging rates of durable responses in the previously treated
metastatic urothelial carcinoma and metastatic renal cell carcinoma
No dose-limiting toxicity was observed in the study. Based on general tolerability, the recommended cabozantinib dose for the expanded dose cohorts and for future late stage evaluation has been determined as cabozantinib at 40 mg daily oral dose combined with nivolumab at 3 mg/kg every 2 weeks and ipilimumab at 1 mg/kg every 3 weeks for 4 doses.
Treatment-related grade 3 or 4 adverse events (>5 percent of patients) observed in the doublet combination included lipase increased (16 percent), hypophosphatemia (14 percent), neutrophil count decreased (12 percent), hypertension (8 percent), fatigue (6 percent) and infection (6 percent). Grade 3 or 4 adverse events (>5 percent of patients) observed in the triplet combination included hypophosphatemia (21 percent), lymphocyte count decreased (14 percent), lipase increased (14 percent), ALT increased (10 percent), AST increased (10 percent), hypertension (10 percent), diarrhea (10 percent), hypokalemia (10 percent), fatigue (7 percent), hyponatremia (7 percent) and amylase increased (7 percent). Grade 3 or 4 immune-related adverse events for the doublet combination included colitis, aseptic meningitis and hepatitis (one patient each) and for the triplet combination were colitis (one patient) and hepatitis (two patients). There were no treatment-related deaths.
“We greatly value our collaboration with NCI-CTEP on this study, which
suggests that the combination of cabozantinib with immune checkpoint
inhibitors may have the potential to improve outcomes for patients with
genitourinary malignancies, including urothelial and renal cell
About the Trial
The trial is sponsored by the
The updated data report on findings from 78 patients with previously treated genitourinary malignancies. Forty-nine patients were treated with the doublet combination of cabozantinib and nivolumab at four dose levels and 29 patients were treated with the triplet combination of cabozantinib, nivolumab and ipilimumab at four dose levels.
The primary endpoint of the phase 1 trial is to determine the dose-limiting toxicity and recommended doses of the doublet and triplet combinations for later stage clinical studies. The secondary endpoint is clinical response rate as assessed by RECIST 1.1. The initial part of the study included four dosing levels: cabozantinib 40 mg daily plus nivolumab 1 mg/kg once every 2 weeks; cabozantinib 40 mg daily plus nivolumab 3 mg/kg once every 2 weeks; cabozantinib 60 mg daily plus nivolumab 1 mg/kg once every 2 weeks; and cabozantinib 60 mg daily plus nivolumab 3 mg/kg once every 2 weeks.
The study also included an additional four dosing levels: cabozantinib 40 mg daily, nivolumab 1 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for 4 doses, then nivolumab 1 mg/kg every 2 weeks; cabozantinib 40 mg daily, nivolumab 3 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for 4 doses, then nivolumab 3 mg/kg every 2 weeks; cabozantinib 60 mg daily, nivolumab 3 mg/kg plus ipilimumab 1 mg/kg every 3 weeks for 4 doses, then nivolumab 3 mg/kg every 2 weeks; and cabozantinib 40 mg daily, nivolumab 1 mg/kg plus ipilimumab 3 mg/kg every 3 weeks for 4 doses, then nivolumab 1 mg/kg every 2 weeks.
Data from the study evaluating the combination of cabozantinib with
nivolumab with or without ipilimumab in patients with previously treated
genitourinary tumors were previously presented by Dr. Apolo at the
About Genitourinary Cancers
Genitourinary cancers are those that affect the urinary tract, bladder, kidneys, ureter, prostate, testicles, penis or adrenal glands — parts of the body involved in reproduction and excretion — and include renal cell carcinoma (RCC) and urothelial carcinoma.1
The American Cancer Society’s 2018 statistics cite kidney cancer as among the top ten most commonly diagnosed forms of cancer among both men and women in the U.S.2 Clear cell RCC is the most common type of kidney cancer in adults.3 If detected in its early stages, the five-year survival rate for RCC is high; for patients with advanced or late-stage metastatic RCC, however, the five-year survival rate is only 12 percent, with no identified cure for the disease.4 Approximately 30,000 patients in the U.S. and 70,000 globally require treatment.5
Urothelial cancers encompass carcinomas of the bladder, ureter and renal pelvis at a ratio of 50:3:1, respectively.6 Urothelial carcinoma occurs mainly in older people; 90 percent of patients with bladder cancer are 55 years or older.7 Bladder cancer is the fourth most common cancer in men and accounts for about five percent of all new cases of cancer in the U.S. each year.7,8 In 2014, an estimated 696,440 people were living with bladder cancer in the U.S.8
About CABOMETYX® (cabozantinib)
CABOMETYX tablets are approved in
CABOMETYX is not indicated for the treatment of refractory mUC and other genitourinary tumors.
U.S. Important Safety Information
Founded in 1994,
Exelixis Forward-Looking Statement Disclaimer
This press release contains forward-looking statements, including,
without limitation, statements related to: the clinical and therapeutic
potential of the combination of cabozantinib with immune checkpoint
inhibitors for patients with genitourinary malignancies, including
urothelial and renal cell carcinoma; potential future studies exploring
the combination of cabozantinib with immune checkpoint inhibitors across
a range of advanced genitourinary cancers, including urothelial cancer;
and Exelixis’ commitment to reinvesting in its business to maximize the
potential of its pipeline, including supplementing its existing
therapeutic assets through targeted business development activities and
internal drug discovery. Words such as “potential,” “future,”
“commitment,” “intend,” or other similar expressions identify
forward-looking statements, but the absence of these words does not
necessarily mean that a statement is not forward-looking. In addition,
any statements that refer to expectations, projections or other
characterizations of future events or circumstances are forward-looking
statements. These forward-looking statements are based upon Exelixis’
current plans, assumptions, beliefs, expectations, estimates and
projections. Forward-looking statements involve risks and uncertainties.
Actual results and the timing of events could differ materially from
those anticipated in the forward-looking statements as a result of these
risks and uncertainties, which include, without limitation: Exelixis’
ability and the ability of its collaborators to conduct clinical trials
of cabozantinib in combination with immune checkpoint inhibitors
sufficient to achieve a positive completion; the potential failure of
cabozantinib in combination with immune checkpoint inhibitors to
demonstrate safety and efficacy in clinical testing; the complexities
and challenges associated with regulatory review and approval processes;
the level of costs associated with Exelixis’ commercialization, research
and development and other activities; competition in the area of
business development activities and the inherent uncertainty of the drug
discovery process; Exelixis’ dependence on its relationships with its
cabozantinib collaboration partners, including, the level of their
investment in the resources necessary to successfully commercialize
cabozantinib in the territories where it is approved; Exelixis’
dependence on its relationship with Genentech/Roche with respect to
cobimetinib and Exelixis’ ability to maintain its rights under the
collaboration; market acceptance of CABOMETYX, COMETRIQ, and COTELLIC
and the availability of coverage and reimbursement for these products;
Exelixis’ dependence on third-party vendors for the development,
manufacture and supply of its products; Exelixis’ ability to protect the
company’s intellectual property rights; market competition; changes in
economic and business conditions, and other factors discussed under the
caption “Risk Factors” in Exelixis’ quarterly report on Form 10-Q filed
with the Securities and Exchange Commission (