GW572016 (Lapatinib) in Treating Patients With Recurrent Prostate Cancer

• The Change in PSA Slope With GW572016 (Lapatinib) [ Time Frame: Assessed every cycle while on treatment; after being off-treatment, assessed every 3 months for 2 years, then every 6 months for 3 years, then annually, for 5 years ] [ Designated as safety issue: No ]
  PSA was evaluated every cycle while on treatment. PSA test results show the level of PSA detected in the blood. These results were reported as nanograms of PSA per milliliter (ng/mL) of blood. PSA slope is the change in PSA level over time. A sharp rise in the PSA level raises the suspicion of cancer and may indicate a fast-growing cancer.
• Progression-free Survival Rate at 2 Years [ Time Frame: Assessed every cycle while on treatment; after being off-treatment, assessed every 3 months for 2 years, then every 6 months for 3 years, then annually for 5 years ] [ Designated as safety issue: No ]
  Proportion of patients who are living with a disease that does not get worse at 2 years from registration based on Kaplan-Meier method.
• Relationship Between Progression-free Survival and EGFR Expression Levels [ Time Frame: Assessed every cycle while on treatment; after being off-treatment, assessed every 3 months for 2 years, then every 6 months for 3 years, then annually for 5 years ] [ Designated as safety issue: No ]
  The association between EGFR (epidermal growth factor receptor) expression levels and the length of time during and after treatment in which a patient is living with a disease that does not get worse.

RATIONALE: GW572016 (lapatinib) may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

PURPOSE: This phase II trial is studying how well GW572016 (lapatinib) works in treating patients with recurrent prostate cancer.

OBJECTIVES:

Primary

• Determine the percentage of patients with hormone-sensitive recurrent prostate cancer treated with GW572016 (lapatinib) who experience > 50% decline in serum prostate-specific antigen (PSA).

Secondary

• Determine the duration of PSA decline in patients treated with this drug.
• Determine the change in slope of a linear graph depicting PSA values in these patients before, during, and after treatment with this drug.
• Determine the safety and tolerability of this drug in these patients.
• Determine the time to progression and 2-year progression-free survival of patients treated with this drug.
• Correlate epidermal growth factor receptor expression/signaling with change in PSA in patients treated with this drug.

OUTLINE: This is a multicenter study.

Patients receive oral GW572016 (lapatinib) once daily on days 1-28. Courses repeat every 28 days in the absence of disease progression or unacceptable toxicity.

After completion of study treatment, patients are followed every 3 months for 2 years, every 6 months for 3 years, and then annually for 5 years.

PROJECTED ACCRUAL: A total of 50 patients will be accrued for this study within 12 months.

• Liu G, Chen Y, Pins M, et al.: E5803: A phase II trial of lapatinib (GW572016) in patients with recurrent prostate cancer as evident by a rising PSA. [Abstract] American Society of Clinical Oncology 2008 Genitourinary Cancers Symposium, Feb 14-16, 2008, San Francisco, CA. A-169, 2008.
• Liu G, Chen YH, Kolesar J, Huang W, Dipaola R, Pins M, Carducci M, Stein M, Bubley GJ, Wilding G. Eastern Cooperative Oncology Group Phase II Trial of lapatinib in men with biochemically relapsed, androgen dependent prostate cancer(,). Urol Oncol. 2011 Jul 22. [Epub ahead of print]

Inclusion Criteria:

• Histologically confirmed prostate cancer

• Biochemical disease progression after prior definitive surgery or radiotherapy, as evidenced by all of the following:

  • Three consecutive rising prostate-specific antigen (PSA) levels obtained ≥ 6 weeks apart within the past 6 months
  • Most recent PSA > 0.4 ng/mL after prostatectomy (1.5 ng/mL after radiotherapy)
  • PSA doubling time < 1 year
• Hormone-sensitive disease, as evidenced by total testosterone > 150 ng/dL within the past 4 weeks
• WBC ≥ 3,000/mm^3
• Granulocyte count ≥ 1,500/mm^3
• Platelet count ≥ 100,000/mm^3
• Bilirubin normal
• Alkaline phosphatase normal
• AST and ALT ≤ 2.5 times upper limit of normal
• PT/INR normal
• Creatinine normal or Creatinine clearance ≥ 60 mL/min
• Cardiac ejection fraction normal by echocardiogram or MUGA within the past 4 weeks
• Prior radiotherapy, surgery or local ablative procedures as curative salvage therapy allowed
• At least 1 year since prior neoadjuvant or adjuvant chemotherapy or hormonal therapy
• At least 1 year since prior therapy that modulates testosterone levels (e.g., luteinizing hormone-releasing hormone agonists/antagonists or antiandrogens)
• At least 1 year since prior investigational agents
• More than 6 months since prior 5α-reductase inhibitors, megestrol, systemic steroids, ketoconazole or herbal supplements
• At least 7 days to 6 months since prior CYP3A4 inducers or inhibitors as determined by the treating physician
• Age 18 and over
• ECOG Performance status 0-1
• Able to swallow and retain oral medication
• Fertile patients must use effective contraception

Exclusion Criteria:

• Metastatic disease
• Other malignancy within the past 5 years except curatively treated nonmelanoma skin cancer

• Unstable arrhythmias on ECG

  • Rate-controlled asymptomatic atrial fibrillation allowed
• Symptomatic congestive heart failure
• Unstable angina pectoris

• GI tract disease resulting in either of the following:

  • Malabsorption syndrome
  • Requirement for IV alimentation
• Uncontrolled inflammatory GI disease (e.g., Crohn's disease or ulcerative colitis)
• Ongoing or active infection
• Psychiatric illness or social situation that would preclude study compliance
• History of allergic reaction attributed to compounds of similar chemical or biologic composition to lapatinib
• Other uncontrolled illness
• Prior vaccine therapy or immunotherapy for prostate cancer
• Prior surgery affecting gastrointestinal (GI) tract absorption
• Concurrent ketoconazole
• Concurrent CYP3A4 inducers or inhibitors
• Concurrent antacids within 1 hour before or after study drug administration
• Other concurrent investigational agents or anticancer therapy
• Concurrent antiretroviral therapy for HIV-positive patients