Retrospective, non-interventional, longitudinal, multi-cohort/parallel group study to assess the safety, tolerability, and efficacy of analgesic therapy with cannabinoids vs. non-cannabinoids in CKD patients with peripheral neuropathic pain/muscle pain depending on the degree of renal impairment (ICD10: N18.1-5) using depersonalized 6-month data from the German Pain e-Registry (CANRELIEF)

Study type

• Study topic:
  Human medicinal product
• Study type:
  Non-interventional study
• Scope of the study:
  Effectiveness study (incl. comparative)

  Safety study (incl. comparative)
• Data collection methods:
  Secondary use of data

Non-interventional study

• Non-interventional study design:
  Cohort

Study drug and medical condition

• Medicinal product name, other:
  cannabis-based medicine; standard analgesics and co-analgesics
• Medical condition to be studied:
  Chronic kidney disease
• Additional medical condition(s):
  nociceptive and neuropathic pain

Population studied

• Short description of the study population:
  Retrospective, non-interventional evaluation of depersonalized routine-data provided by the German Pain e-Registry on patients with chronic kidney disease who suffer from nociceptive or neuropathic pain and who received either an analgesic standard treatment with guideline recommended drugs or a cannabis-based alternative.
• Age groups:
  • Adult and elderly population (≥18 years)

    • Adults (18 to < 65 years)

      • Adults (18 to < 46 years)
      • Adults (46 to < 65 years)
    • Elderly (≥ 65 years)

      • Adults (65 to < 75 years)
      • Adults (75 to < 85 years)
      • Adults (85 years and over)
• Special population of interest:
  Renal impaired
• Estimated number of subjects:
  2054

Study design details

• Study design:
  Retrospective, non-interventional evaluation of depersonalized routine-data provided by the German Pain e-Registry on patients with chronic kidney disease who suffer from nociceptive or neuropathic pain and who received either an analgesic standard treatment with guideline recommended drugs or a can
• Main study objective:
  The primary objective of this non-interventional study is to comparatively evaluate the safety, tolerability, and efficacy of cannabis-based pain therapy (CAM) compared to conventional pain therapy with analgesics and co-analgesics recommended by guidelines (NCAM) in adult patients with varying degrees of chronic renal impairment (ICD-10: N18.1-5) under everyday conditions.
• Setting:
  For this purpose, routine data from the German Pain E-Register will be mirrored, anonymized, and stratified into two treatment cohorts according to defined inclusion and exclusion criteria. To ensure comparable baseline values, a so-called propensity score matching (PSM) is performed, in which each patient treated with CAM is matched with a patient treated with NCAM [in terms of age, gender, pain phenotype, duration of illness, degree of renal dysfunction, etc. (Note: Patients for whom no suitable “partner” from the other treatment group can be found in the PSM are excluded from the analysis without replacement; a PSM performed in mid-2025 based on the above-mentioned target criteria identified 1027 evaluable patients with at least 6 months of follow-up data for each of the two comparison groups). In addition to demographic data and baseline data, treatment-related changes in pain intensity (lowest, mean, and highest 24-hour pain intensity values, 24-hour pain index – PIX), pain-related impairments (modified Pain Disability Index, mPDI), pain-related impairments of mood and affect (DASS-21, areas of depression, anxiety, and stress), pain-related limitations of quality of life (Quality-of-Life Impairment by Pain Inventory, QLIP), as well as daily cannabis dose and the need for or use of other analgesics and co-analgesics were recorded at three assessment points: baseline (i.e., immediately before the start of cannabis therapy) and at the end of months 3 and 6 of treatment.
• Comparators:
  Cannabis-based analgesics (CAM: either pure THC, THC-dominant, CBD-dominant, or pure CBD) will be compared to conventional Non-Cannabis pain medications.
• Outcomes:
  Primary endpoint of CANRELIEF is the percentage of patients who did not discontinue pain medication due to adverse drugs reactions (ADR) and who reported a clinically relevant improvement vs. baseline (i.e. a symptom relief equal to or even greater than the minimal clinical important difference for the resepctive parameter and/or at least 30%) for a) average 24-hr. pain intensity index (PIX), b) modified pain disability index (mPDI), c) pain-related sleep disturbances (mPDI subscale #6), d) quality-of-life impairment by pain (QLIP), e) overall wellbeing, f) number of days impaired by pain in the last 3 months, and g) overall impact of pain in the last 3 months.
• Data analysis plan:
  The primary endpoint, like all other efficacy and tolerability analyses conducted as part of this study, will be evaluated for the “as observed” (AOD) data set and as part of a sequential non-inferiority/superiority analysis. All analyses are based on a comparison of the data at the end of the third/sixth month with the corresponding baseline data.