Adults 18 to 59, any sex, with Safety or Pharmacokinetics. Patients with the condition only — healthy volunteers not accepted.
Results — posted to ClinicalTrials.gov
Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.
Number of Participants With Treatment-Emergent Adverse Events (TEAEs)Primary· Day 1 through Day 7
For purposes of monitoring safety, treatment-emergent adverse events (AEs) will be graded using the National Cancer Institute's Common Terminology Criteria for Adverse Events (version 5.0).
Cmax (ng/mL) will be evaluated for: mitragynine, 7 hydroxy-mitragynine, paynantheine, speciogynine, and speciociliatine
Mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
41.664
± 14.766
Cohort 2, 3 g of Kratom
118.002
± 46.816
Cohort 3, 8 g of Kratom
197.496
± 88.333
Cohort 4, 10 g of Kratom
318.112
± 163.400
Cohort 5, 12 g of Kratom
378.507
± 184.981
7 hydroxy-mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
6.728
± 2.182
Cohort 2, 3 g of Kratom
17.751
± 8.687
Cohort 3, 8 g of Kratom
33.985
± 11.184
Cohort 4, 10 g of Kratom
48.388
± 19.989
Cohort 5, 12 g of Kratom
58.400
± 22.717
Paynantheine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
7.7
± 2.6
Cohort 2, 3 g of Kratom
19.0
± 5.0
Cohort 3, 8 g of Kratom
29.7
± 14.6
Cohort 4, 10 g of Kratom
66.7
± 36.6
Cohort 5, 12 g of Kratom
65.8
± 34.2
Speciogynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
6.3
± 1.9
Cohort 2, 3 g of Kratom
15.8
± 4.3
Cohort 3, 8 g of Kratom
23.2
± 10.1
Cohort 4, 10 g of Kratom
58.9
± 35.5
Cohort 5, 12 g of Kratom
55.5
± 31.0
Speciociliatine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
39.1
± 11.7
Cohort 2, 3 g of Kratom
106.6
± 23.9
Cohort 3, 8 g of Kratom
168.9
± 68.1
Cohort 4, 10 g of Kratom
388.1
± 217.2
Cohort 5, 12 g of Kratom
409.7
± 193.8
Time of Maximum Observed ConcentrationSecondary· 0, 0.25, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00, 4.00, 6.00, 8.00, 10.00, 12.00, 24.00 and 48.00 hours post-dose
Tmax (hours) will be evaluated for: mitragynine, 7 hydroxy-mitragynine, paynantheine, speciogynine, and speciociliatine
mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
4.02
2.50 – 6.18
Cohort 2, 3 g of Kratom
2.99
2.50 – 4.00
Cohort 3, 8 g of Kratom
5.04
2.50 – 6.14
Cohort 4, 10 g of Kratom
3.50
2.50 – 4.00
Cohort 5, 12 g of Kratom
2.00
1.00 – 6.01
7 hydroxy-mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
4.02
2.50 – 6.18
Cohort 2, 3 g of Kratom
3.50
2.99 – 4.00
Cohort 3, 8 g of Kratom
6.01
3.00 – 10.02
Cohort 4, 10 g of Kratom
4.00
3.00 – 4.00
Cohort 5, 12 g of Kratom
2.75
1.50 – 6.01
paynantheine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
4.02
2.50 – 6.18
Cohort 2, 3 g of Kratom
2.99
2.50 – 4.00
Cohort 3, 8 g of Kratom
5.04
3.00 – 6.14
Cohort 4, 10 g of Kratom
3.00
2.50 – 4.00
Cohort 5, 12 g of Kratom
3.29
1.50 – 6.01
speciogynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
4.02
2.50 – 6.18
Cohort 2, 3 g of Kratom
3.00
2.99 – 4.00
Cohort 3, 8 g of Kratom
5.04
3.00 – 10.02
Cohort 4, 10 g of Kratom
4.00
3.00 – 6.00
Cohort 5, 12 g of Kratom
2.54
1.50 – 6.01
speciociliatine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
4.02
3.00 – 8.04
Cohort 2, 3 g of Kratom
5.00
3.00 – 9.99
Cohort 3, 8 g of Kratom
8.07
3.00 – 12.00
Cohort 4, 10 g of Kratom
5.00
4.00 – 8.00
Cohort 5, 12 g of Kratom
5.06
2.00 – 10.01
Area Under the Concentration Time Curve From Time Zero to the Time of Last Quantifiable Concentration (AUC0-T)Secondary· 0, 0.25, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00, 4.00, 6.00, 8.00, 10.00, 12.00, 24.00 and 48.00 hours post-dose
AUC0-T (ng\*h/mL) will be evaluated for: mitragynine, 7 hydroxy-mitragynine, paynantheine, speciogynine, and speciociliatine
mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
305.383
± 115.616
Cohort 2, 3 g of Kratom
784.794
± 380.290
Cohort 3, 8 g of Kratom
1942.205
± 737.483
Cohort 4, 10 g of Kratom
3254.385
± 2213.450
Cohort 5, 12 g of Kratom
3271.209
± 1577.443
7 hydroxy-mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
53.518
± 21.615
Cohort 2, 3 g of Kratom
132.994
± 85.838
Cohort 3, 8 g of Kratom
412.602
± 153.549
Cohort 4, 10 g of Kratom
459.109
± 226.314
Cohort 5, 12 g of Kratom
574.260
± 194.789
paynantheine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
47.0
± 19.0
Cohort 2, 3 g of Kratom
132.9
± 44.0
Cohort 3, 8 g of Kratom
320.2
± 134.0
Cohort 4, 10 g of Kratom
725.2
± 452.4
Cohort 5, 12 g of Kratom
727.6
± 397.9
speciogynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
53.4
± 19.2
Cohort 2, 3 g of Kratom
154.0
± 44.1
Cohort 3, 8 g of Kratom
341.0
± 147.5
Cohort 4, 10 g of Kratom
819.2
± 521.6
Cohort 5, 12 g of Kratom
790.0
± 453.2
speciociliatine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
573.9
± 285.4
Cohort 2, 3 g of Kratom
1910.9
± 475.4
Cohort 3, 8 g of Kratom
3359.2
± 1257.7
Cohort 4, 10 g of Kratom
7904.8
± 4790.9
Cohort 5, 12 g of Kratom
7449.8
± 3695.4
Area Under the Concentration Time Curve Extrapolated to InfinitySecondary· 0, 0.25, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00, 4.00, 6.00, 8.00, 10.00, 12.00, 24.00 and 48.00 hours post-dose
AUC0-inf (ng\*h/mL) will be evaluated for: mitragynine, 7 hydroxy-mitragynine, paynantheine, speciogynine, and speciociliatine
AUC0-inf/D (ng\*h/mL/g) will be evaluated for: mitragynine, 7 hydroxy-mitragynine, paynantheine, speciogynine, and speciociliatine
mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
341.941
± 131.703
Cohort 2, 3 g of Kratom
299.134
± 145.479
Cohort 3, 8 g of Kratom
288.131
± 133.599
Cohort 4, 10 g of Kratom
395.044
± 283.954
Cohort 5, 12 g of Kratom
306.217
± 149.248
7 hydroxy-mitragynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
57.023
± 21.974
Cohort 2, 3 g of Kratom
46.441
± 29.497
Cohort 3, 8 g of Kratom
54.821
± 21.166
Cohort 4, 10 g of Kratom
51.516
± 28.427
Cohort 5, 12 g of Kratom
49.707
± 17.178
paynantheine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
58.3
± 22.6
Cohort 2, 3 g of Kratom
53.4
± 17.5
Cohort 3, 8 g of Kratom
47.5
± 20.2
Cohort 4, 10 g of Kratom
81.9
± 47.8
Cohort 5, 12 g of Kratom
67.9
± 38.6
speciogynine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
76.1
± 27.5
Cohort 2, 3 g of Kratom
63.4
± 17.0
Cohort 3, 8 g of Kratom
51.6
± 23.7
Cohort 4, 10 g of Kratom
95.9
± 57.1
Cohort 5, 12 g of Kratom
75.5
± 45.4
speciociliatine
Group
Value
95% CI
Cohort 1, 1 g of Kratom
654.9
± 377.1
Cohort 2, 3 g of Kratom
699.9
± 192.9
Cohort 3, 8 g of Kratom
523.4
± 195.9
Cohort 4, 10 g of Kratom
890.8
± 513.0
Cohort 5, 12 g of Kratom
667.7
± 339.6
Maximum Effect for Drug LikingSecondary· 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, and 24 hours postdose
Maximum (peak) effect (Emax) for Drug Liking assessed on a bipolar (0 to 100 points) visual analog scale (VAS). Anchors will be presented using text such as "strong disliking" (score = 0), "neither like nor dislike" (score = 50) to "strong liking" (score = 100).
Group
Value
95% CI
Cohort 1, 1 g of Kratom
50.7
± 0.67
Cohort 2, 3 g of Kratom
51.7
± 1.67
Cohort 3, 8 g of Kratom
60.2
± 8.17
Cohort 4, 10 g of Kratom
52.2
± 0.98
Cohort 5, 12 g of Kratom
68.7
± 9.22
Placebo
50.2
± 0.13
Maximum Effect for Overall Drug LikingSecondary· 12 and 24 hours postdose
Maximum (peak) effect (Emax) for Overall Drug Liking assessed on a bipolar (0 to 100 points) visual analog scale (VAS). Anchors will be presented using text such as "strong disliking" (score = 0), "neither like nor dislike" (score = 50) to "strong liking" (score = 100).
Group
Value
95% CI
Cohort 1, 1 g of Kratom
50.2
± 0.17
Cohort 2, 3 g of Kratom
50
± 0
Cohort 3, 8 g of Kratom
61.8
± 8.37
Cohort 4, 10 g of Kratom
55.7
± 13.22
Cohort 5, 12 g of Kratom
67
± 7.96
Placebo
45.1
± 4.9
Maximum Effect for Take Drug AgainSecondary· 12 and 24 hours postdose
Maximum (peak) effect (Emax) for Take Drug Again assessed on a bipolar (0 to 100 points) visual analog scale (VAS). Anchors will be presented using text such as "definitely would not" (score = 0), "neither would nor would not" (score = 50) to "definitely would" (score = 100).
Group
Value
95% CI
Cohort 1, 1 g of Kratom
53.3
± 3.14
Cohort 2, 3 g of Kratom
50.0
± 0
Cohort 3, 8 g of Kratom
65.2
± 8.04
Cohort 4, 10 g of Kratom
49.8
± 17.17
Cohort 5, 12 g of Kratom
61
± 8.57
Placebo
45.9
± 5.2
Maximum Effect for HighSecondary· Predose and 0.25, 0.5, 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, 12, and 24 hours postdose
Maximum (peak) effect (Emax) for High assessed on an unipolar (0 to 100 points) visual analog scale (VAS). Anchors will be presented using text such as "not at all" (score = 0) to "extremely" (score = 100).
Group
Value
95% CI
Cohort 1, 1 g of Kratom
0.5
± 0.5
Cohort 2, 3 g of Kratom
1.2
± 1.17
Cohort 3, 8 g of Kratom
10.8
± 4.94
Cohort 4, 10 g of Kratom
8.5
± 5.33
Cohort 5, 12 g of Kratom
46.3
± 14.14
Placebo
0.4
± 0.31
Adverse events — posted to ClinicalTrials.gov
Time frame: 37 days..
Reporting threshold: 0%.
Adverse-event reports describe events observed during the trial — not all are caused by the drug.
Kratom (Mitragyna speciosa) is a plant often used to self-treat conditions such as pain, coughing, diarrhea, anxiety and depression, opioid use disorder, and opioid withdrawal. Due to limited data availability, the goal of this clinical trial is to learn about safety, pharmacokinetics (what the body does to the drug) and pharmacodynamics (what the drug does to the body) of Kratom in adult recreational polydrug users with opioid experience.
Publications & conference data
No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.
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Sponsor: as reported to ClinicalTrials.gov by Altasciences Company Inc.
Last refreshed: 29 September 2025
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT06072170.