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for people ages 30 years and up (full criteria)
at San Francisco, California and other locations
study started
estimated completion:



The purpose of this large comparative effectiveness study led by Richard J. Barohn, MD, of the University of Kansas Medical Center, is to learn about the safety and effectiveness of nortriptyline, duloxetine, pregabalin and mexiletine in treating cryptogenic sensory polyneuropathy (CSPN).

Official Title

Patient Assisted Intervention for Neuropathy: Comparison of Treatment in Real Life Situations (PAIN-CONTRoLS)


The goal of this research project is to find the best drug for the treatment of pain in patients with CSPN. While the pharmaceutical industry has focused attention on drugs for treating diabetic sensory neuropathy (DSPN), and two drugs are now FDA approved, there have not been any prospective trials in CSPN. And, because there are no studies with CSPN patients, insurance carriers often reject authorizing prescriptions for some drugs for patients with CSPN.

There are four drugs that will be tested in this study: nortriptyline, duloxetine, pregabalin and mexiletine. These drugs are not approved by the FDA for the treatment of CSPN and are considered "investigational" in this study.

There are two periods in this study: Screening/Baseline and Study Drug. During the Screening/Baseline period the researchers will determine eligibility for potential subjects. During the second period, eligible patients who consented to participate will take the study drug. Participants will be randomized to receive one of the four drugs in this study. Participants will know which drug they are taking. Participants will not be allowed to switch groups and receive a different drug during the study.

This study uses an adaptive study design. This means the study can enroll less participants and provide better conclusions. The study design allows the researchers the ability to make changes to the approach of the study or to stop the study early if there are strong results.


Cryptogenic Sensory Polyneuropathy CSPN neuropathy pain pain management Polyneuropathies Pregabalin Duloxetine Hydrochloride Nortriptyline Mexiletine


You can join if…

Open to people ages 30 years and up

  • Diagnosis of cryptogenic sensory polyneuropathy.
  • Likert Pain Score of greater than or equal to 4.
  • Must not currently be on nortriptyline, duloxetine, pregabalin or mexiletine or similar class of medication for at least 7 days from baseline study visit.

You CAN'T join if...

  • Any medical condition or current medication that would prevent them from taking either nortriptyline, duloxetine, pregabalin or mexiletine.
  • Unable to give consent.
  • Unable or not willing to comply with the study.
  • Other causes for polyneuropathy.


  • University of California San Francisco
    San Francisco, California, 94143, United States
  • California Pacific Medical Center
    San Francisco, California, 94107, United States
  • Cedars-Sinai Medical Center
    Los Angeles, California, 90048, United States


in progress, not accepting new patients
Start Date
Completion Date
University of Kansas Medical Center
Phase 4
Study Type
Last Updated
August 7, 2017