Viventia’s Proxinium gets EU orphan drug status

The EMEA orphan drug designation for Proxinium, Viventia’s lead product candidate, follows the FDA’s decision to confer orphan status upon the drug for this indication in January.

Proxinium combines a powerful cytotoxic protein payload with the highly precise tumor-targeting characteristics of a monoclonal antibody. The antibody fragment of Proxinium targets EpCAM – an antigen that is highly expressed on many epithelial cancers including head and neck cancer, ensuring that the payload is delivered directly to the tumor.

Proxinium has completed two phase I exploratory human clinical trials. In one of these trials, final efficacy analysis showed that 25% of patients who expressed the therapeutic target for Proxinium had a complete response to therapy, 63% had an objective response and 88% had tumor growth control.

In the other trial, Proxinium injected intratumorally on a monthly schedule yielded an objective response rate of 43% and a tumor growth control rate of 71% from those patients that expressed the EpCAM antigen. The median survival rate for EpCAM positive patients who showed a response to Proxinium reported from this study was 301 days, compared to a median survival of 125 days for those patients that were EpCAM negative.

“Proxinium has produced positive efficacy results in patients with refractory head and neck cancer and is on track to commence late-stage clinical trials this year,” said Dr Nick Glover, president and CEO of Viventia. “Orphan drug status provides Proxinium with up to ten years of market exclusivity in Europe and will ensure that our regulatory strategy for the EU is supported.”