Lilly, Pfizer stop development of osteoarthritis drug after FDA rejection, extending bleak run for NGF inhibitors 

The NGF inhibitor class has claimed yet another victim. After seeing regulators on both sides of the Atlantic knock back filings for approval, Eli Lilly and Pfizer have stopped global clinical development of tanezumab.

In 2011, the FDA put the NGF inhibitor class on clinical hold over evidence linking the drugs to joint damage and other adverse events. Companies including AbbVie, AstraZeneca and Johnson & Johnson stopped work on NGF inhibitors in the years after the FDA action but a small band of drug developers forged ahead, culminating in Lilly and Pfizer seeking approval for tanezumab in osteoarthritis.

The continued development of NGF inhibitors was always seen as a high risk, high reward effort. For Lilly and Pfizer, evidence that the gamble would fail to pay off arrived earlier this year, when first the FDA and then, just last month, the European Medicines Agency rejected requests for approval.

Lilly has now confirmed tanezumab has reached the end of the line, using its third quarter results to reveal it and Pfizer have discontinued the global clinical development program for the NGF inhibitor.

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The action ends a mammoth effort to get tanezumab over the line. At an investor event, Angela Hwang, group president of the Pfizer biopharmaceuticals group, said the tanezumab filing to the FDA probably contained “the most amount of data that we've ever submitted for any submission to date here at Pfizer.” The size of the filing reflected a long development process and a complex risk-benefit picture.

Lilly and Pfizer’s decision to call time on tanezumab further thins a once-vibrant class of candidates. Regeneron still lists fasinumab, a Teva-partnered NGF inhibitor, in its pipeline but the comprehensive rejection of tanezumab has further diminished expectations for the drug. In April, Teva CEO Kåre Schultz told investors the FDA advisory committee vote against tanezumab was “definitely a negative for the product class,” adding that nonessential fasinumab costs are on hold pending a decision on whether to file for approval.