- Pfizer and Eli Lilly on Wednesday announced positive topline results for their osteoarthritis pain drug tanezumab in a Phase 3 trial of 698 patients.
- The study showed a statistically significant improvement in pain, physical function and patient overall assessment of osteoarthritis. No further details of the data were disclosed at this time.
- Safety data showed that 1% of patients discontinued due to adverse events, the companies said. Rapidly progressing osteoarthritis occurred in less than 1.5% of tanezumab-treated patients — but not at all in the placebo patients — while no events of osteonecrosis were seen.
While the efficacy of tanezumab appears positive, it's the safety profile that analysts and investors are closely watching. Tanezumab is from a class of drugs called nerve growth factor (NGF) inhibitors. The class as a whole has shown strong signs of effectiveness, but has been plagued by clinical holds due to safety problems. Tanezumab has not gone unscathed.
Pfizer announced the clinical hold and suspension of the program in June 2010 due to increased risk of rapidly progressing osteoarthritis in patients taking the drug. The program resumed in March 2015, and Lilly paid $200 million upfront at the time to sign on.
But other companies have seen problems too; a study of an NGF inhibitor being developed by Regeneron Pharmaceuticals and Teva Pharmaceuticals was put on hold in October 2016 for the same reason — the companies later discontinued the highest dose of the drug, called fasinumab.
For Lilly, tanezumab is part of its push into neuroscience and chronic pain. The Indianapolis pharma has been making a strategic shift into the space as its key diabetes franchise struggles. Pfizer, on the other hand, announced earlier this year that it is pulling out of neuroscience, with tanezumab being one of the few drugs in the space it is retaining.
Tanzemuab is also being studied in chronic low back pain and cancer pain caused by bone metastases. A large safety study of the drug is expected to report out in the first half of next year and will be an important gauge of its profile.
The osteoarthritis market is expected to grow at a compound annual growth rate of 6.8% through 2023, according to a report by Market Research Future, due to an aging population and rising rates of obesity, both of which put pressure on joints.
Late last year, the Food and Drug Administration approved Flexion Therapeutics' Zilretta (triamcinolone acetonide) for osteoarthritis knee pain. The drug is not an NGF inhibitor, but is being billed as a non-surgical, non-opioid option for pain.