Erlotinib has activity in androgen-independent prostate cancer (AIPC) patients who are chemotherapy-naive: A phase II trial

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Background: Mechanisms of hormone resistance for AIPC are variable. One proposed mechanism is the over expression of the epidermal growth factor receptor (EGFR) which in turn stimulates proliferation through its pathway. We aimed to determine the efficacy of an oral anti-EGFR inhibitor (erlotinib) in this patient population that was chemotherapy-naive. The primary end point was to evaluate the overall clinical benefit defined as the sum of complete response (CR), partial response (PR), and stable disease (SD). Methods: Between January and December 2006, sixteen patients were enrolled onto this phase II study. Median age was 78 years (66–85). Median PSA was 61.9 (9.2–800.2). Median time from initial diagnosis until starting Erlotinib was 7.8 years. Erlotinib was given daily at 150 mg until disease progression. Patients were evaluated every 2 weeks for toxicity. Response assessment took place every 2 cycles (each cycle was 4 weeks). Evaluations included computed tomography of measurable disease areas, bone scans, and serum PSAs. Patients who progressed radiographically but maintained a PSA response or those who progressed biochemically but maintained a radiographic response were considered stable and were allowed to continue on study. Results: Sixteen patients were enrolled with 14 being evaluable at this time (2 patients are early in their course). Median cycles received is 2 (range 1.5–12). One patient achieved a PR and continues on Erlotinib after one year of enrollment. Three patients demonstrated stable disease but two of them later progressed. One patient withdrew after 9 days of starting therapy due to fatigue and poor taste. All other patients developed disease progression after two cycles of therapy. The calculated overall clinical benefit was 28% (4 responses out of 14 patients). One patient died from pneumonia and seizures unrelated to Erlotinib as confirmed by an autopsy that showed progression in the central nervous system. Erlotinib was well-tolerated with skin rash and diarrhea being the most common toxicities. Conclusions: Erlotinib has clinical activity as a single agent in AIPC. Updated results of this ongoing study will be presented at the meeting. Further studies with this agent alone or in combination are warranted.

No significant financial relationships to disclose.

Combination of chemotherapy with interleukin-2 and interferon alfa for the treatment of metastatic melanoma

PURPOSE

The primary objective of this clinical study was to assess the feasibility of administering recombinant interleukin-2 and recombinant interferon alfa-2a before and after combination cytotoxic chemotherapy. After encouraging initial responses, the study was expanded to further evaluate the therapeutic potential, clarify the toxicities of this regimen, and explore any associated immunologic changes.

PATIENTS AND METHODS

Eighty-four patients with metastatic melanoma, including patients with brain metastases, were treated on this 6-week protocol. Patients received combination cisplatin (25 mg/m2/d) and dacarbazine (220 mg/m2/d) on days 1 through 3 and 22 through 24 plus carmustine (150 mg/m2) on day 1. Interleukin 2 (13.5 million IU/m2/d) and interferon alfa (6 MU/m2/d) were administered on days 4 through 8 and 17 through 21.

RESULTS

Among 83 patients assessable for response, 12 complete and 34 partial responses were documented (55% response rate). The median time to disease progression was 7 months, the median survival from study entry was 12.2 months, and the median survival from diagnosis of metastatic disease was 15.5 months. Although patients were hospitalized to receive treatment, intensive care unit support generally was not needed. Dose-limiting toxicities were related to elevations in serum bilirubin and serum creatinine levels. No patient developed a grade 4 clinical toxicity. Treatment produced a skin depigmentation, which was associated with prolonged survival.

CONCLUSION

A plateau in both the survival and time to progression curves beyond 2 years (15% of the patients) and a greater than 10% disease-free survival beyond 4 years indicate that there may be a long-term benefit for some patients. The limited toxicity of this regimen should permit its use in most oncology settings. A randomized trial of chemoimmunotherapy versus chemotherapy should be performed to establish the value of chemoimmunotherapy for melanoma.