A new Johnson & Johnson drug trial has put Amgen on the defensive. According to the 903-patient study, J&J's experimental drug ustekinumab (Stelara) proved more effective at treating psoriasis than Amgen's blockbuster Enbrel was. "We've never really seen clearance [of psoriasis] along the lines of what we've seen with ustekinumab," one of the trial's lead investigators told the Wall Street Journal.
Amgen fired back, saying that the J&J trial only lasted 12 weeks, and so it didn't address the new drug's long-term safety. Enbrel has a "consistent safety profile," an Amgen spokeswoman said, and 16 years of clinical experience. It's true that the FDA is digging into links between the fungal infection histoplasmosis and TNF-alfa meds, but only 17 of the 240 cases occurred among Enbrel patients. Stelara works via a different mode of action than Enbrel does: It's an interleukin inhibitor, rather than a TNF blocker.
Amgen's safety focus may be well targeted. The FDA recently delayed approving the J&J drug for three months, with a decision now expected in December; this after the FDA advisory panel unanimously recommended approval. The expert panel did discuss worries about possible cancer risks with Stelara, and according to the WSJ Health Blog, safety appears to be the FDA's overriding concern. “We have submitted a summary of safety data to the FDA but efficacy will probably not play a major role in the approval," a J&J biologics exec told the blog. We'll have to wait and see what the agency decides.