N0377: Results of NCCTG phase II trial of the mTOR inhibitor RAD-001 in metastatic melanoma

8530

Background: RAD-001 (Everolimus) is an oral inhibitor of mammalian target of rapamycin (mTOR). Interim analysis results from a phase II study of RAD-001 in patients with metastatic melanoma (MM) were presented at ASCO 2005. This study was re-opened using a higher dose based on an improvement in the 16 week progression free survival (PFS) rate and good tolerability. Methods: A two- stage, phase II multi-institutional trial was conducted in patients with MM to assess that 16 weeks PFS rate was at least 50%. Inclusion criteria: measurable disease, ECOG performance score of 0–2. Exclusion criteria: presence of intracranial metastases, concurrent use of inducers of cytochrome 3A4 and abnormal organ function. The dose of RAD-001 in the second cohort was increased to 10 mg daily (increased from 30 mg weekly) based on evidence of safety of the higher dose. Results: Twenty-nine patients were enrolled; baseline information is available on 27. Median age was 63 yrs; 15 (56%) had >2 sites of metastatic disease. Most (48%) had stage M1c disease. PS was 0, 1 and 2 in 58%, 38% and 4%. All but 4 (15%) had received prior therapy. Grade 3 adverse events included stomatitis and fatigue (2 each), leukopenia, neutropenia, diarrhea, anorexia, dehydration, dyspnea, hyperglycemia, and hypersensitivity (1 each). Planned interim analysis was done after 20 patients were enrolled. 14 (70%) had progressed 16 weeks, failing to meet the decision rule needed (PFS >30%) to restart accrual. The median PFS for all 29 patients was 56 days. The median overall survival (OS) has not been reached. For the entire cohort of 53 pts treated on this study (at both dose levels), the median PFS, median OS were 59 and 286 days respectively. Conclusion: Interim analysis after enrollment of 20 patients at a higher dose of RAD-001 demonstrated significantly more toxicity and no added clinical efficacy. The 16 week PFS rate target was not reached, and accrual was suspended.

No significant financial relationships to disclose.

Phase II trial of the mTOR inhibitor everolimus (RAD-001) in metastatic melanoma

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Background: Mammalian target of rapamycin (mTOR) is a serine-threonine kinase that regulates the production vascular endothelial growth factor (VEGF) and cell growth and proliferation. Inhibitors of mTOR have anti-mitotic and anti-angiogenic effects in various cancers (including melanoma). Everolimus (RAD-001), an orally administered inhibitor of mTOR, is well tolerated at a dose of 30 mg/week. We conducted a phase II study to evaluate the role of RAD-001 in treating patients with metastatic melanoma (MM). Methods: A 2 stage, phase II multi-institutional trial was conducted in patients with MM to assess progression free survival (PFS) rate at 16 weeks was at least 50% against the alternative it was at most 30%. Data about expected baseline PFS were derived from historical controls. Each cycle was 8 weeks in duration. Inclusion criteria: measurable disease, ECOG performance score (PS) of 0–2. Exclusion criteria: presence of intracranial metastases, concurrent use of inducers of cytochrome 3A4 and abnormal hepatic, renal or bone marrow function. Correlative studies included changes pharmacodynamic endpoints to evaluate effect of therapy on signaling pathways. Results: 24 patients with MM were enrolled. Median age was 56 years (33–79), 21 (88%) had at 2 or more sites of metastatic disease. Most (75%) had stage M1c, with 13% each having 1a and 1b disease. PS was 0, 1 and 2 in 58, 38% and 4%, resp. All but 9 had received previous therapy for MM. Planned interim analysis was done after 20 patients were enrolled. Of these, 7 (i.e., 35%) were PF at 16 weeks, which exceeded the decision rule for restarting accrual. No patient had an objective response; all 7 had stable disease. There were no grade 3 toxicities. Grade 2 toxic events (at least possibly related to therapy) were: fatigue (17%), diarrhea (8%) and anemia (8%). Patients had a clinically relevant benefit, with the median PFS for all 24 patients of 3 months. Median overall survival was not reached. Three patients continue on therapy. RAD-001 treatment resulted in changes in serum VEGF levels. Conclusion: Interim analysis after enrollment of 20 patients suggests that RAD-001 is well tolerated and has sufficient anti-tumor activity in MM to warrant the opening of enrollment to the second stage of this trial. Further accrual is planned.

No significant financial relationships to disclose.

Chemotherapy for advanced CNS ependymoma

BACKGROUND

The role of chemotherapy in recurrent ependymoma is poorly defined. This study was performed to help clarify the benefits of chemotherapy in this setting.

PATIENTS AND METHODS

We retrospectively reviewed the charts of patients with advanced ependymoma of the CNS who received chemotherapy in our institution between 1974 and 1993, inclusive. Sixteen consecutive patients were treated with regimens containing either nitrosourea, platinum, or other combinations exclusive of nitrosourea or platinum. No patient received nitrosourea and platinum concurrently. Two methods were used to define response. The first was a direct comparison of radiographic images before and after chemotherapy more than one month apart. A second broader definition of response that employed four other criteria in addition to imaging studies (symptoms, signs, performance status, and neurologic functional status) was also used.

RESULTS

Results were as follows (response rate by imaging studies followed by response rate by scoring in parenthesis): Platinum-based chemotherapy resulted in a 67% (83%) response rate with 33% (0%) remaining stable. Nitrosourea-based regimens resulted in a 25% (60%) response rate with 50% (10%) remaining stable. When combinations other than platinum or nitrosourea were used, 11% (22%) responded and 56% (44%) remained stable. Relative differences in response rates between chemotherapy regimens persisted when the data were analyzed by grade. Median time to progression was 6, 10, and 3 months, respectively.

CONCLUSION

Platinum-based chemotherapy regimens appear to result in higher response rates with lower rates of progression than nitrosourea-based regimens. Other regimens that do not include cisplatinum or nitrosourea appear to be even less effective.