Initial results from a Phase evaluation of a novel, orally-active cancer drug in development at AstraZeneca indicate that the compound can achieve long-lasting stabilisation of disease in patients with a range of solid tumours.

The compound, called AZD6244, inhibits MEK1/2, an enzyme that plays a role in cell pathways that regulate proliferation and survival in a number of cancers, including lung, pancreatic, colon, melanoma and thyroid cancer. It is currently in Phase II testing patients with melanoma, pancreatic, lung and colon cancers and was licensed by AstraZeneca from Array BioPharma.

The results of the trial were presented at the EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in Prague yesterday by Prof Alex Adjei of the Mayo Clinic in the USA.

Patients in the study were randomised to receive 100 or 200mg doses, twice a day for 28-day cycles. The larger dose proved to be too high for continuous dosing due to adverse side effects, but the smaller dose was well tolerated over a prolonged period.

Among those patients who completed two cycles of treatment, 49% had stable disease, with nine of them remaining stable for five months or more.

The result “demonstrate that a dose of 100mg of AZD6244 is well tolerated, produces a high incidence of long-lasting stable disease, and is associated with a profound inhibition of ... cell signalling and a reduction in cell proliferation – which indicates that the drug is working against the tumours,” said Prof Adjei.