Investigation of Safety and Tolerability of ASP3652 Based on Clinical Studies of Cerebrospinal Fluid Transfer After Multiple Doses and Exposure After Single Doses at High Dose Levels

Adv Ther. 2020 Sep;37(9):3967-3984. doi: 10.1007/s12325-020-01451-6. Epub 2020 Jul 26.

Abstract

Introduction: The studies described here were conducted to investigate the central nervous system (CNS) transfer of ASP3652, a peripherally acting inhibitor of fatty acid amide hydrolase, after multiple doses at around the anticipated therapeutic dose and the safety, tolerability, and pharmacokinetics after single doses at corresponding supratherapeutic doses in healthy subjects.

Methods: Study 1 was an open-label multiple dose study in which ASP3652 (300 mg bid) or matching placebo was administered in multiple doses to healthy subjects. Study 2 was a placebo-controlled, randomized 4 × 4 crossover study in which ASP3652 was given as three single ascending doses of ASP3652 (600-1800 mg) or matching placebo to healthy subjects. Levels of ASP3652 and endocannabinoids (eCBs) in plasma, cerebrospinal fluid (CSF) (study 1 only), and safety were evaluated.

Results: In study 1, ASP3652 was readily absorbed to reach Cmax at 1 h after dosing. AUCtau and Cmax of ASP3652 in CSF were approximately 0.2% and 0.06% of the AUCtau and Cmax in plasma after multiple doses of ASP3652 300 mg bid. At steady state the area under the response-time curve (AURC) from 0 to 12 h and the maximum response for anandamide in plasma were approximately 550-fold and 230-fold higher than those in CSF. In study 2, the Cmax and AUC of ASP3652 increased higher than dose proportionally in subjects receiving 600-1800 mg ASP3652. For eCBs, although the AURC increased less than dose proportionally, maximum plasma levels were comparable across all treatment groups. The incidence of adverse events (AEs) was similar across all treatment groups including the placebo group. There was no evidence of CNS-related side effects.

Conclusions: ASP3652 showed low CNS penetration at the anticipated therapeutic dose and was well tolerable without any CNS-related AEs at supratherapeutic doses, supporting that the drug can be safely tested at the anticipated therapeutic dose.

Trial registration: ClinicalTrials.gov identifier, NCT02034734 for study 1, NCT01815684 for study 2.

Keywords: Anandamide; Cerebrospinal fluid; Endocannabinoid; Fatty acid amide hydrolase; Healthy subjects; Pharmacodynamics; Pharmacokinetics.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Amidohydrolases / antagonists & inhibitors*
  • Amidohydrolases / blood
  • Amidohydrolases / metabolism
  • Amidohydrolases / therapeutic use*
  • Cerebrum / metabolism*
  • Cross-Over Studies
  • Dose-Response Relationship, Drug*
  • Double-Blind Method
  • Female
  • Healthy Volunteers
  • Humans
  • Male
  • Middle Aged
  • Netherlands
  • Young Adult

Substances

  • Amidohydrolases
  • fatty-acid amide hydrolase

Associated data

  • ClinicalTrials.gov/NCT02034734
  • ClinicalTrials.gov/NCT01815684
  • ClinicalTrials.gov/NCT02034734