Does Ziconotide work?
Yes, in large controlled trials. The key trial had 111 people.
Approval rested on randomized placebo-controlled trials of intrathecal ziconotide, including a 111-patient trial in cancer and AIDS pain published in JAMA in 2004 that showed a 53 percent improvement in pain scores versus 18 percent on placebo. The approved use matches the trial populations, so A, with the note that the early trials used faster titration than is now recommended and had high adverse-event rates. 12
In the JAMA trial by Staats and colleagues, 111 patients had cancer or AIDS. Their pain was uncontrolled by whole-body or intrathecal opioids. Researchers randomized them to intrathecal ziconotide or placebo. The dose was raised over 5 to 6 days. Mean pain scores on a visual analog scale improved 53 percent with ziconotide and 18 percent with placebo. Half the ziconotide patients had at least moderate relief. On placebo it was 18 percent. Five ziconotide patients became pain-free. 1
The label summarizes three placebo-controlled trials in 457 patients. It describes one in detail. That trial used a slower three-week titration in severe chronic pain. It found a 12 percent mean improvement in pain scores versus 5 percent on placebo. This was a smaller but significant effect. The faster titration of the earlier trials caused substantially more adverse events. 2
Evidence checklist
- Randomised controlled trial Randomised placebo-controlled trials
- Human study over 100 people Cited trial 111 patients
- More than one research group Article does not say who ran the trials
- Clinical outcomes, not surrogate markers Pain score improvement 53% vs 18%
- Human safety data beyond case reports Boxed warning; frequent psychiatric events
More on Ziconotide
Citations
Reference information only, not medical advice. Drawn from the Ziconotide article, fact-checked against the cited sources. No dosing anywhere on this site.