A Phase 1 interventional study of Istradefylline and Phentermine 45 mg in Drug Abuse, sponsored by Kyowa Kirin Co., Ltd.. Completed at 1 site in United States. Open to participants aged 18 Years to 55 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2024-04-25.
Sponsored by Kyowa Kirin Co., Ltd. · Phase 1, Interventional, and Other
This study is to evaluate the abuse potential of single-doses of istradefylline compared to placebo and phentermine in recreational stimulant users. Subjects will participate in an outpatient medical Screening visit, a 5-day Qualification (Drug Discrimination) Phase, a 6-period Treatment Phase, and an outpatient safety Follow-Up visit. Study will be approximately 25 weeks total.
Within 28 days of the Screening visit, eligible subjects will be admitted to the CRU (Day -1) for the Qualification Phase. During the Qualification Phase, subjects will receive single oral doses of phentermine 60 mg and matching placebo in a randomized, double blind, crossover manner, with each drug administration separated by approximately 48 hours (Day 1 and Day 3), to ensure that they can discriminate and show positive subjective effects of the active controls. Following evaluation of eligibility, subjects may be discharged (those who fail Qualification criteria) or remain in the CRU (those who pass criteria and are eligible) and then proceed directly to the Treatment Phase. The washout interval between last drug administration in the Qualification Phase and first drug administration in the Treatment Phase will be at least 96 hours (4 days).
Following confirmation of eligibility from the Qualification Phase, subjects will be randomized to one of 6 treatment sequences according to a 6x6 Williams square. Subjects will receive single oral doses of each of the 6 treatments in a randomized, double-blind, crossover manner, Istradefylline 40 mg, Istradefylline 80 mg, Istradefylline 160 mg, Phentermine 45 mg, Phentermine 90 mg, Placebo.
Each drug administration will be separated by at least 21 days. Serial pharmacodynamic evaluations will be conducted up to 24 hours after each study drug administration to confirm exposure to istradefylline.
2,181 studies on the registry are indexed under Substance-Related Disorders; 399 are open to participants now.
This study's enrollment of 42 is below the median of 108 across 1,770 interventional studies indexed under Substance-Related Disorders.
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Exclusion Criteria:
40 mg istradefylline (1 × 40 mg tablet + 3 × placebo tablets + 3 × placebo capsules)
Drug: Istradefylline · Other: Placebo
80 mg istradefylline (2 × 40 mg tablets + 2 × placebo tablets + 3 × placebo capsules)
Drug: Istradefylline · Other: Placebo
160 mg istradefylline (4 × 40 mg tablets + 3 × placebo capsules)
Drug: Istradefylline · Other: Placebo
45 mg phentermine (4 x placebo tablets + 3 × 15 mg phentermine hydrochloride capsules)
Drug: Phentermine 45 mg · Other: Placebo
90 mg phentermine (4 × placebo tablets + 3 × 30 mg phentermine hydrochloride capsules)
Drug: Phentermine 45 mg · Other: Placebo
Placebo (4 × placebo tablets + 3 × placebo capsules)
Other: Placebo
Istradefylline 40, 80, 160 mg
Also known as: 6002
Phentermine 45 or 90 mg
Placebo
Drug Liking VAS
To evaluate the abuse potential of istradefylline compared to phentermine and placebo.
Time frame: 24 hours
C-SSRS (Columbia Suicide Severity Rating Scale)
To evaluate the safety and tolerability of istradefylline.
Time frame: 24 hours
Alerness/Drowsiness, Agitation/Relaxation VAS
To evaluate the safety and tolerability of istradefylline.
Time frame: 24 hours
Caffine Withdrawal/Symptom Questionnaire
To evaluate the safety and tolerability of istradefylline.
Time frame: 24 hours
Overall Drug Liking, Take Drug Again VAS
To evaluate the safety and tolerability of istradefylline.
Time frame: 24 hours
Drug Similarity VAS
To evaluate the safety and tolerability of istradefylline.
Time frame: 24 hours
This study is completed, as verified in Aug 2016. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Istradefylline