Shares in Threshold Pharmaceuticals jumped more than 10% on news that US regulators are fast-tracking its Merck KGaA-partnered anticancer drug TH-302 for soft tissue sarcomas, a group of aggressive cancers of the connective tissues.

The US Food and Drug Administration Fast Track status should in theory speed up the review of the drug - which is targeted at previously untreated patients with metastatic or locally advanced unresectable STS - and indicates that it has the potential to address unmet medical needs.

TH-302, for which the German drugmaker signed a co-development deal potentially worth more than $500 million to Threshold, is a hypoxia-activated prodrug currently in late-stage trials for both STS and pancreatic cancer, as well as in earlier studies for other solid tours and blood malignancies.

The US group said primary analysis of overall survival data from the trial should be carried out during the first quarter of 2016. 

TH-302 holds orphan designations in both the US and EU.