Aeterna Zentaris announces perifosine Phase 1 trial on neuroblastoma

Aeterna Zentaris Inc. (NASDAQ: AEZS) (TSX: AEZ) (the "Company") today announced that Phase 1 trial results for its oral PI3K/Akt inhibitor, perifosine, showed the drug's activity against chemo-resistant and radio-resistant neuroblastoma, while allowing good quality of life and sparing vital organs. Neuroblastoma is a type of childhood cancer which usually begins in nerve tissues. Data were presented yesterday by Brian H. Kushner, MD, of the Memorial Sloan-Kettering Cancer Center in New York, during a poster session at the Advances in Neuroblastoma Research Conference which is being held in Toronto, Canada.

The Study

This was an open-label dose-escalating Phase 1 trial to assess toxicity and efficacy of perifosine, given in monotherapy to patients with neuroblastoma (clinicaltrials.gov NCT00776867). Patients were dosed using 50mg tablets and received a loading dose (100-200mg/m²) of perifosine on day 1, followed by daily maintenance doses (50-75mg/m²) until progressive disease or dose-limiting toxicity. Disease evaluation was every 8 weeks.

The poster reported on the outcome of 24 patients treated to date; patients had a median age of 8.7 years (range 4.7 to 33.5) and a median disease duration of 4.6 years (range 2.5 to 8.0). Three patients were treated for neuroblastoma refractory to primary therapy, and 21 for neuroblastoma resistant to salvage therapy after 1 to 5 (median 2) prior relapses. Prior therapy included high-dose conventional induction and 2^nd line chemotherapy (all patients); myeloablative chemotherapy and stem cell transplantation (10 patients) and/or targeted radiotherapy with I-131-MIBG (9 patients).

Results

Anti-neuroblastoma activity was evident by a 50% progression-free survival rate at 12 months (Standard Error ±11%) and included 1 complete remission (CR) based on a normalized MIBG scan and 3 patients with improved MIBG scan and normalized bone marrow histology over prolonged follow-up (up to 37+months). No significant toxicity was seen, in particular no grade 3 problems, and no safety issues were encountered in 6 patients who started treatment with pre-existing thrombocytopenia and/or grade 3 elevations in liver enzymes.

Conclusions

• Perifosine was well tolerated, without major toxicity - hence, compatible with good quality of life;
• Perifosine monotherapy may help in progression-free survival of patients with persistent/stable MIBG-positivity in skeletal sites;
• Perifosine may have a possible role with chemotherapy, radiation therapy, and/or other agents active in PI3K/Akt pathway.

Juergen Engel, PhD, President and CEO at Aeterna Zentaris stated, "These data again emphasize perifosine's anticancer activity, as was the case earlier this week with the article published in Cancer, outlining perifosine's anticancer activity in renal cell carcinoma. On both occasions, the authors alluded to perifosine's potential as a combination therapy which further supports our current Phase 3 trial in multiple myeloma in which perifosine is used in combination with bortezomib and dexamethasone."