Pfizer and Eli Lilly are getting ready to restart Phase III clinical trials for experimental chronic pain drug tanezumab, after US regulators lifted the partial clinical hold on the programme.

Trials involving tanezumab and all other anti-nerve growth factor antibodies were suspended in December 2012 because of adverse changes observed in the sympathetic nervous system of mature animals. 

But following a review of nonclinical data on the sympathetic nervous system response to the humanised monoclonal antibody, the US Food and Drug Administration has now issued a green light for studies to resume. 

“We are pleased with the FDA’s decision as chronic pain remains an area of significant unmet medical need and we believe tanezumab has potential to offer a new, non-narcotic option,” said Steve Romano, head of Global Medicines Development at Pfizer’s Global Innovative Pharmaceuticals Business.

As a result, Pfizer expects to receive a $200 million upfront payment from Lilly under their collaboration agreement.