Increasing placebo responses over time in U.S. clinical trials of neuropathic pain

  title={Increasing placebo responses over time in U.S. clinical trials of neuropathic pain},
  author={Alexander H. Tuttle and Sarasa Tohyama and Tim Ramsay and Jonathan Kimmelman and Petra Schweinhardt and Gary J. Bennett and Jeffrey S. Mogil},
Abstract Recent failures of clinical trials of novel analgesics designed to treat neuropathic pain have led to much speculation about the underlying reasons. One often discussed possibility is that the placebo response in these trials has increased in recent years, leading to lower separation between the drug and placebo arms. Whether this has indeed occurred has not yet been adequately addressed. Here, we extracted data from published randomized controlled trials (RCTs) of drugs for the… 
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