Radiation Therapy and Ixabepilone in Treating Patients With High-Risk Stage III Prostate Cancer After Surgery

OBJECTIVES:

Primary

- To determine the maximum-tolerated dose and dose-limiting toxicity of ixabepilone in
combination with concurrent intensity-modulated radiation therapy in patients with
high-risk prostate cancer after prostatectomy. (Phase I)

- To determine the toxicity profile of this regimen in these patients. (Phase I)

Secondary

- To assess freedom from progression in patients treated with this regimen. (Phase II)

- To assess biochemical failure, local failure, and distant failure in patients treated
with this regimen. (Phase II)

- To assess disease-specific survival and overall survival of patients treated with this
regimen. (Phase II)

- To evaluate acute and late toxicity of this regimen in these patients.

OUTLINE: This is a phase I, dose-escalation study of ixabepilone followed by a phase II
study.

Patients undergo adjuvant intensity-modulated radiation therapy once daily, 5 days a week,
for 7-9 weeks. Patients also receive concurrent ixabepilone IV over 1 hour on days 1 and 8.
Treatment with ixabepilone repeats every 21 days for 3 courses in the absence of disease
progression or unacceptable toxicity.

After completion of study therapy, patients are followed up every 3 months for 1 year, every
6 months for 3 years, and then annually for 6 years.

DISEASE CHARACTERISTICS:

- Diagnosis of adenocarcinoma of the prostate

- Must have undergone any common form of prostatectomy (e.g., open, perineal,
laparoscopic, or robotic) within the past 2 years

- T3 disease or positive surgical margins

- Node negative (N0) and free of distant metastasis (M0) by a bone scan and CT scan
or MRI of the pelvis within the past 90 days

- Considered high-risk disease

- Gleason score = 7 and post-operative PSA > 0 and ≤ 2 ng/mL OR Gleason score ≥ 8 and
post-operative PSA ≥ 0 and ≤ 2 ng/mL

- Pre-prostatectomy PSA available

- Range of pre-prostatectomy PSA values not required

PATIENT CHARACTERISTICS:

- Zubrod (ECOG) performance status 0-1

- ANC ≥ 2,000/mm^3

- Platelet count ≥ 100,000/mm^3

- Hemoglobin ≥ 8 g/dL

- Total bilirubin < 1.5 times upper limit of normal (ULN)

- AST and ALT < 2.5 times ULN

- Alkaline phosphatase < 2.5 times ULN

- Fertile patients must use effective contraception during and for 4 weeks after
completion of study therapy

- Patients with urinary incontinence waiting for stabilization of urinary function after
prostatectomy allowed for up to 6 months

- No CTCv4 peripheral neuropathy (motor or sensory) ≥ grade 1

- No history of inflammatory colitis including Crohn disease or ulcerative colitis

- No significant history of psychiatric illness

- No other invasive malignancy within the past 3 years except adequately treated
nonmelanoma skin cancer or carcinoma in situ of the oral cavity

- No severe, active co-morbidity with any of the following:

- Unstable angina and/or congestive heart failure requiring hospitalization within
the past 6 months

- Transmural myocardial infarction within the past 6 months

- Acute bacterial or fungal infection requiring IV antibiotics

- Chronic obstructive pulmonary disease exacerbation or other respiratory illness
requiring hospitalization or precluding study therapy within 30 days

- Immunocompromised patients or AIDS based upon current CDC definition

- HIV testing not required

- No history of hypersensitivity reactions to agents containing Cremophor® EL or its
derivatives (e.g., polyoxyethylated castor oil)

PRIOR CONCURRENT THERAPY:

- See Disease Characteristics

- No prior pelvic radiotherapy or radiotherapy for another malignancy that encompasses ≥
30% of major bone marrow-containing areas (e.g., pelvis or lumbar spine)

- No prior hormonal therapy for prostate cancer

- Prior hormonal agents, e.g., finasteride or dutasteride, for benign prostatic
hypertrophy allowed

- No other concurrent adjuvant antineoplastic therapy planned while on this protocol,
including the following:

- Cryotherapy

- Hormonal therapy

- Other chemotherapy for prostate cancer

- Prior chemotherapy for a different type of cancer allowed provided it was
administered > 3 years ago