FDA removes the brakes on Pfizer and Lilly's pain drug

A once-halted pain candidate from partners Pfizer ($PFE) and Eli Lilly ($LLY) now has the green light to resume late-stage testing, as the FDA has lifted a clinical hold tied to some serious safety concerns for the whole class of drugs.

The treatment, tanezumab, works by targeting nerve growth factor, a protein that regulates how the body processes pain. Back in 2010, NGF inhibitors seemed poised to become blockbusters and upend the market for chronic pain treatments, with analysts forecasting group sales north of $11 billion a year. But emerging ties between NGF blockade and dangerous changes to the nervous system and joint destruction spurred widespread concerns and eventually led the FDA to clamp down, putting a hold on tanezumab in 2012.

Despite the then-indefinite delay on Pfizer's antibody, Lilly stepped in in 2013 with a $1.8 billion deal to partner up on the drug, believing the regulatory climate would soon change and NGF inhibitors would fall back into vogue.

Now, after presenting the agency with some preclinical data demonstrating tanezumab's safety, the pair is back in business, Pfizer said, resuming Phase III development where it left off in 2012. Tanezumab is in development as a treatment for chronic pain tied to osteoarthritis, lower back issues and cancer.

Under Lilly's license deal, Pfizer gets $200 million based on the FDA's action, and Lilly has promised $350 million in regulatory milestones and about $1.2 billion more tied to sales.

"We're pleased to work with Pfizer to resume the Phase III program, and we're confident that tanezumab, if approved, can be an innovative treatment with the potential to help millions suffering from painful conditions," Lilly Bio-Medicines President David Ricks said in a statement.

The FDA's change of heart could have a read-through for some other paused NGF programs, including efforts from Johnson & Johnson ($JNJ), AstraZeneca ($AZN) and Regeneron ($REGN).

- read the statement