A Phase 2 interventional study of KDT-3594 and Placebo in Parkinson Disease, sponsored by Kissei Pharmaceutical Co., Ltd.. Completed at 1 site in Japan. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-10.
Sponsored by Kissei Pharmaceutical Co., Ltd. · Phase 2, Interventional, and Treatment
This trial is a late phase II, multicenter, randomized, double-blind, placebo-controlled, parallel group trial to evaluate the efficacy, safety, and pharmacokinetics of KDT-3594 administered at escalating doses ranging from 0.25 to 2 mg per day for 17 weeks in patients with advanced PD with levodopa.
This trial is a late phase II, multicenter, randomized, double-blind, placebo-controlled, parallel group trial to evaluate the efficacy, safety, and pharmacokinetics of KDT-3594 administered once daily in patients with advanced PD with levodopa.
4,573 studies on the registry are indexed under Parkinson Disease; 1,086 are open to participants now.
This study's enrollment of 178 is above the median of 40 across 3,353 interventional studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →Kissei Pharmaceutical Co., Ltd. is the lead sponsor of 63 studies on the registry; 3 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
MMSE and MoCA
Short tests of memory and thinking, each scored out of 30. Lower scores suggest more difficulty; criteria give a range, either to include people with memory problems or to leave them out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
KDT-3594 capsules will be orally administered at escalating doses ranging from 0.25 to 2 mg per day for 17 weeks.
Drug: KDT-3594
Placebo capsules will be orally administered at escalating doses ranging from 0.25 to 2 mg per day for 17 weeks.
Drug: Placebo
Oral administration
Oral administration
Change from baseline in the MDS-UPDRS Part II+III (ON-time) total score at Week 17 of the treatment period
MDS-UPDRS is a multimodal scale assessing impairment and disability consisting of 4 parts. (Part I; 13 items) non-motor experiences of daily living, (Part II; 13 items) motor experiences of daily living completed by the participants, (Part III; 33 items) motor examination of PD and was administered by the rater, and (Part IV; 6 items) motor complication integrates participant-derived information with the rater's clinical observations and judgements and is completed by the rater. For each question, a numeric score was assigned between 0-4, where 0 = Normal, 1 = Slight, 2 = Mild, 3 = Moderate, 4 = Severe. In all parts, a higher score indicated more severe symptoms of PD, and the score range of each part are as follows. * Part I: 0-52 * Part II: 0-52 * Part III: 0-132 * Part IV: 0-24 * Total Score: 0-260 * Part II+III: 0-184 (MDS-UPDRS Part II and III combined score equals the sum of Parts II and III (range 0-184)).
Time frame: Up to 17 weeks
Change from baseline in the MDS-UPDRS Part II+III (ON-time) total score
MDS-UPDRS is a multimodal scale assessing impairment and disability consisting of 4 parts. (Part I; 13 items) non-motor experiences of daily living, (Part II; 13 items) motor experiences of daily living completed by the participants, (Part III; 33 items) motor examination of PD and was administered by the rater, and (Part IV; 6 items) motor complication integrates participant-derived information with the rater's clinical observations and judgements and is completed by the rater. For each question, a numeric score was assigned between 0-4, where 0 = Normal, 1 = Slight, 2 = Mild, 3 = Moderate, 4 = Severe. In all parts, a higher score indicated more severe symptoms of PD, and the score range of each part are as follows. * Part I: 0-52 * Part II: 0-52 * Part III: 0-132 * Part IV: 0-24 * Total Score: 0-260 * Part II+III: 0-184 (MDS-UPDRS Part II and III combined score equals the sum of Parts II and III (range 0-184)).
Time frame: Up to 17 weeks
Change from baseline in the MDS-UPDRS Part I, II, III, and IV (ON-time) total score
MDS-UPDRS is a multimodal scale assessing impairment and disability consisting of 4 parts. (Part I; 13 items) non-motor experiences of daily living, (Part II; 13 items) motor experiences of daily living completed by the participants, (Part III; 33 items) motor examination of PD and was administered by the rater, and (Part IV; 6 items) motor complication integrates participant-derived information with the rater's clinical observations and judgements and is completed by the rater. For each question, a numeric score was assigned between 0-4, where 0 = Normal, 1 = Slight, 2 = Mild, 3 = Moderate, 4 = Severe. In all parts, a higher score indicated more severe symptoms of PD, and the score range of each part are as follows. * Part I: 0-52 * Part II: 0-52 * Part III: 0-132 * Part IV: 0-24 * Total Score: 0-260 * Part II+III: 0-184 (MDS-UPDRS Part II and III combined score equals the sum of Parts II and III (range 0-184)).
Time frame: Up to 17 weeks
Response rate in the MDS-UPDRS Part III (ON-time) total score
MDS-UPDRS is a multimodal scale assessing impairment and disability consisting of 4 parts. (Part I; 13 items) non-motor experiences of daily living, (Part II; 13 items) motor experiences of daily living completed by the participants, (Part III; 33 items) motor examination of PD and was administered by the rater, and (Part IV; 6 items) motor complication integrates participant-derived information with the rater's clinical observations and judgements and is completed by the rater. For each question, a numeric score was assigned between 0-4, where 0 = Normal, 1 = Slight, 2 = Mild, 3 = Moderate, 4 = Severe. In all parts, a higher score indicated more severe symptoms of PD, and the score range of each part are as follows. * Part I: 0-52 * Part II: 0-52 * Part III: 0-132 * Part IV: 0-24 * Total Score: 0-260 * Part II+III: 0-184 (MDS-UPDRS Part II and III combined score equals the sum of Parts II and III (range 0-184)).
Time frame: Up to 17 weeks
Change from baseline in the proportion of OFF-time in awake time
Time frame: Up to 17 weeks
Change from baseline in OFF-time
Time frame: Up to 17 weeks
Incidence of adverse events and treatment-related adverse events
Time frame: Up to 17 weeks
Plan to share: No
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Studies of the drug tested here: KDT-3594
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