Inclusion Criteria:

- Patient has given signed informed consent.

- Patient has documented histologically confirmed malignant melanoma or renal cell
carcinoma which is metastatic.

- Patient is eligible for high dose IV IL-2 therapy.

- Tumor dimension of at least one lesion is measurable in two dimensions.

- Patient is at least 18 years of age.

- Patient is ambulatory with good performance status (ECOG PS 0,1; Karnofsky 100-70%).

- If the patient is a woman of child bearing potential, patient is not lactating and
ahs a negative pregnancy test (beta-HCG test obtained within 72 hours of enrollment)
and agrees to use an adequate method of contraception for the duration of the study.

- Patient has adequate organ function as defined by:

- WBC count >3,500 per cubic millimeter; platelet count> 100,000 per cubic
millimeter;

- Bilirubin within institutional normal range; creatinine less than or equal to
2.0 mg/dl or creatinine clearance > 50 ml/min;

- No evidence of congestive heart failure, symptoms of coronary artery disease,
serious cardiac arrhythmias or evidence of prior myocardial infarction. A
pretreatment cardiac stress test must be performed within 42 days of IL-2
treatment. Patients with documented ischemia on the pretreatment cardiac stress
test will be excluded from the study;

- Adequate pulmonary reserve. Pulmonary function tests (PFTs) must be performed
within 42 days of IL-2 treatment and an FEV1 > 2.0 liters or 75% of predicted
for height and age is the minimum acceptable criteria for patient entry.
PAtients unable to perform PFTs will be excluded from the study.

- Patient has recovered from all toxic effects of prior therapy.

- Patient has a life expectancy, in the opinion of the investigator, of at least 4
months.

Exclusion Criteria:

- Patient has an organ allograft.

- Patient has brain metastases. A Brain CT or MRI scan should be performed within 42
days of IL-2 treatment.

- Patient is know to be HIV antibody positive. HIV testing is not required for
enrollment into this study.

- Patient has evidence of active infection which requires antibiotic therapy.

- Patient has received systemic corticosteroids in the four weeks prior to the first
dose of study drug, or requires or is anticipated to require corticosteroids for
intercurrent disease.

- Patient has received radiotherapy, chemotherapy, or immunotherapy in the four weeks
prior to the first dose of study drug, or is scheduled to receive concurrent
radiotherapy, chemotherapy, or immunotherapy.

- Patient has contraindication to treatment with pressor agents.

- Patient currently receives chronic medication for asthma.

- Patient has a history of another malignancy other than basal cell skin cancer within
5 years prior to the first dose of study drug.

- Patient has any significant medical disease other than the malignancy which, in the
opinion of the investigator, may interfere with completion of the study.

- Patient has previously received any IL-2 therapy.

- Patient has received another investigational medication within 4 weeks prior to
M40403 administration or is scheduled to receive an investigational drug other than
M40403 during the course of the study.