Amid repeated stumbles, Pfizer and Eli Lilly tout their anti-NGF pain drug tanezumab — but questions linger
Pfizer and Eli Lilly have started to make their late-stage case for tanezumab, outlining some positive results on pain but raising some serious issues about just how effective this low-dose pain drug could be.
According to their researchers, the drug, angling for the non-opioid market the feds want to promote, hit statistical significance against a placebo — scoring on 3 out of 3 primary endpoints.
But at least one prominent analyst, Evercore ISI’s Umer Raffat, took a look at the responses for the low doses that made it into late-stage testing and started to raise some serious questions about the commercial value of an anti-NGF.
According to Raffat:
70% responders are 10-12% higher than (placebo) today (vs ~17% in prior trials). Similarly, 90% responders are only ~5% higher than pbo (vs 10-11% in prior trials).
This moderate efficacy is a bigger issue: in the past, a naproxen active comparator was tried … and results today on pbo-adj basis sort of mirror those naproxen results on several metrics.
A decade ago, analysts were competing in projecting multibillion-dollar markets for the NGF crowd. But expectations have dropped after the development world was forced to cut back on doses — 20 mg to 10 mg for Pfizer — in order to overcome the severe safety challenges that had temporarily frozen the entire field.
Lilly nevertheless agreed to put up as much as $1.8 billion to buy into the Pfizer drug.
Regulators halted testing after patients in the studies began to blow their joints out. Concerns about rapidly progressive osteoarthritis recently forced Teva and Regeneron to back off their two high doses for fasinumab.
“(T)his is a high-risk, high-reward program as we’ve described in the past,” Regeneron R&D chief George Yancopoulos told analysts in May. “It’s pretty well-demonstrated that the molecule has activity, but it also has certain side effects. It’s not osteonecrosis, it’s more defined as rapid progression of the osteoarthritis in some patients. And this is something that obviously has been seen with this class and with our molecule before. And so what the independent data monitoring committee did was they obviously took an analysis to look at the benefit and the risk that is the therapeutic benefit compared to their analysis of the risk coming from these rapidly progressive osteoarthritis events and they decided that we should terminate the upper two doses and continue with the two lower doses.”
Raffat appears more satisfied with the safety of tanezumab, but researchers did track a 1.3% rate of aggressive osteoarthritis in the drug arm, with none in the placebo group.
J&J, meanwhile, dropped fulranumab 2 years ago. AstraZeneca abandoned its Medi-578 candidate in 2010 and AbbVie has also dropped another NGF blocker called ABT-110.