Low Dose Ara-C Versus Low Dose Ara-C and Tipifarnib: Result of the UK NCRI AML16 “Pick a Winner” Comparison

Abstract

Novel treatments are needed for older patients with AML who are not thought likely to benefit from standard chemotherapy. A recent randomised trial demonstrated that Low Dose Ara-C (LD Ara-C) was superior to best supportive care (BSC) (Burnett et al Cancer 2007: 109: 1114–1124). The Farnesyl Transferase inhibitor, Tipifarnib, has produced encouraging responses in this patient group (Lancet 109; 1387–1394) although in a subsequent randomised comparison vs BSC it was not superior (Haroussea et al Blood 1997: 110,135a)The UK NCRI AML16 trial aims to test novel agents or combinations in untreated older patients with AML or high risk MDS (marrow blasts >10%) following a “pick a winner” design. The intention is to randomise up to 50 patients per arm with the expectation that a “winner” will achieve a remission rate in excess of 30%, compared with 15–20% with LD Ara-C. If that is achieved randomisation will continue with OS and DFS as endpoints. We report our experience of LD Ara-C (20mg bd days 1–10 for 4 courses versus LD Ara-C combined with Tipifarnib (300mg bd days 1–21) for 4 courses at 6–8 week intervals.Patient Details: Sixty-five patients were randomised between December 2006 and October 2007. The median age was 74.4 years with 82% of patients over 70 years. There were no differences between the treatment arms with respect to age distribution, gender, performance status, de novo/secondary AML, high risk MDS presenting WBC or cytogenetic risk group.Because of concerns about excess deaths in the Tipifarnib arm and therefore the low probability that LD Ara-C + Tipifarnib would be superior to LD Ara-C alone, the DMEC recommended premature closure of the Tipifarnib arm.Conclusions: While other agents combined with Tipifarnib may continue to show promise, the combination with LD-Ara-C in this patient population was not beneficial.