Oxford Biomedica has been boosted by the news that US regulators have approved a series of amendments to a late-stage study for its renal cancer vaccine TroVax which originally failed to meet its primary targets.

The firm says it was granted a meeting with the US Food and Drug Administration last week to discuss the data collected to date from the 733-patient Phase III TRIST study. In July, the independent data safety monitoring board for the study recommended that it should carry on but that further vaccinations be discontinued. The DSMB advised that TroVax administered according to the original protocol will not meet the predefined primary efficacy endpoint.

Now the FDA has “supported all aspects of the revised analytical plan for the study”, Oxford BioMedica says, and the amendments are designed “to explore whether patient outcome is dependent on the number of doses, background standard of care and patients’ prognostic factors”. The revised protocol of the ongoing TRIST study includes additional interim analyses to be conducted at regular intervals.

Oxford BioMedica noted that pending further review of the TRIST interim data and the FDA agreement, partner Sanofi-Aventis says that it is committed to proceed with the planned TroVax Phase III programme in colorectal cancer. John Dawson, acting chief executive, said “we are encouraged by the FDA’s feedback and guidance” and the agreed amendments to TRIST “should enable us to identify the optimal setting and regimen for TroVax in renal cancer”.

He concluded that Oxford BioMedica and Sanofi will continue “to map the optimal development path for TroVax”.