A Pilot Study of the Safety, Efficacy, and Effects on Functional Imaging of the Combination of cG250 and Sunitinib in Patients With Advanced Renal Cell Carcinoma
This study explores the safety, efficacy and effects on functional imaging of the
combination of cG250 and sunitinib in patients with advanced renal cell carcinoma (kidney
When kidney cancer has spread beyond the kidney it is usually not possible to cure it with
surgery. Other treatments such as radiotherapy or chemotherapy are also of limited value.
Kidney cancers often rely on certain proteins for their growth, particularly proteins that
affect the ways that blood vessels grow into the cancer. Ingrowth of blood vessels supplies
cancer cells with oxygen and nutrition; without the blood vessels, cancer deposits can not
grow in size. When growth of the blood vessels is blocked, established cancers may stop
growing or may shrink. This has been shown to work for some drugs that target this process
in kidney cancers. One of these drugs is called sunitinib.
A protein, called G250, is also thought to be important in helping kidney cancers to grow.
G250 is found on the cell surface of many kidney cancers. One possible method of interfering
with the function of G250 is to target G250 with an antibody known as cG250. Clinical trials
with cG250 and have shown it to be safe, to home in on kidney cancer cells, and to persist
in the blood and the cancer tissue for a long period of time.
The main purpose of this study is to explore whether the combination of sunitinib and cG250
is safe in patients with advanced kidney cancer. The study will also assess whether this
combination is able to cause kidney cancer to shrink; will determine where cG250 travels
within the body, whether the immune system reacts to the cG250 and whether sunitinib affects
that; and whether the combination affects how kidney cancers grow or how blood flows within
Patients with advanced kidney cancer who have never previously received cG250, sunitinib (or
similar drugs) may be eligible to participate in the study. A total of 14 patients are
expected to be recruited.
Eligible patients will receive cG250 10 mg/m² by weekly intravenous infusion for five weeks,
followed by a two-week break (one cycle). The first and fifth dose will be trace-labeled
with a radioactive substance (¹²⁴I-cG250) detectable by a special scan called a Positron
Emission Tomography (PET scan) to allow studies of the distribution of cG250. Sunitinib 50
mg by daily oral dose will also be given for 4 weeks (commencing on day 8 of the first
treatment cycle), followed by a two-week break. Up to two cycles of treatment will be
given. If a second cycle is given, cG250 will be given as four weekly doses and daily
sunitinib will start on the same day. No ¹²⁴I-cG250 will be administered after the first
The extent of the kidney cancer will be assessed by CT scan at baseline and at the end of
each treatment cycle. Safety assessments (physical examination, blood tests, gated cardiac
blood pool scan, ECG-heart trace) will be performed at the beginning of each treatment
cycle, repeated throughout the cycle and end of study. A number of blood tests and PET
scans will be done in the first cycle to show how and in what amounts the ¹²⁴I-cG250
distributes in the body. Other PET scans (F-FDG and O-H₂O) will be performed to
allow assessment of tumour growth and blood flow. Blood tests will also show whether the
immune system recognises the infused cG250 by making an antibody against it.
Endpoint Classification: Safety/Efficacy Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
Safety and Tolerability of cG250 and sunitinib in patients with advanced RCC: Adverse events of cG250 administered concurrently with sunitinib
7 -13 weeks
A/Prof Ian D Davis, FRACP, FAChPM, MBBS, PhD
Ludwig Institute for Cancer Research
Australia: Department of Health and Ageing Therapeutic Goods Administration