AstraZeneca has been dealt a blow on the failure of its MEK inhibitor selumetinib to show a significant progression-free survival benefit in patients with a rare eye cancer.

Specific data were not revealed at this time, but AZ said the Phase III SUMIT study assessing selumetinib in combination with dacarbazine for metastatic uveal melanoma did not meet its primary endpoint.

While disappointing, selumetinib’s primary development programme and potential lies in KRAS-mutant advanced non-small cell lung cancer (in combination with docetaxel), and the drug is also being investigated in a Phase III study in differentiated thyroid cancer and a Phase II registration study in neurofibromatosis Type 1.

“The findings from SUMIT have no impact on the other studies and we look forward to presenting the data in due course,” noted Antoine Yver, head of Oncology, Global Medicines Development, at AZ.

The disappointing results for uveal melanoma were somewhat of a surprise given the strength of mid-stage data, but as Berenberg analyst Alistair Campbell also pointed out in client note (according to Reuters), the drug “is not one of the big three oncology drugs (AZD9291, Lynparza and MEDI4736) that will lead the turnaround of Astra's fortunes in oncology”.