The purpose of this study is to identify a suitable dosing regimen of IV baclofen to serve as a temporary substitute for an oral regimen.

Baclofen intravenous solution 2 mg/mL will be manufactured and provided by Allaysis, LLC. Prism Clinical Research will purchase oral baclofen tablets (10 mg) from a commercial supplier. Subject will start baclofen at a 5 mg oral dose every 8 hours. Oral baclofen will be increased incrementally and self-administered over 13 days to a maximum dose of 20 mg every 8 hours. Subjects will be crossed over to 16 mg intravenous baclofen infused over 120 (n=6) or 150 (n=6) minutes every 8 hours for 11 doses. Subjects will be changed back to oral baclofen at a 15 mg dose self-administered every 8 hours and tapered off of baclofen over 15 days. Following the completion of this group of 12 subjects, the remaining 30 subjects will receive IV baclofen at the infusion duration that best meets the criteria for bioequivalence.

Inclusion Criteria:

• Males and females between the ages of 18-45. An attempt will be made to recruit an equal number of men and women into each dosing group; however a ratio of 2:4 in the initial run-in phase and 12:18, with either women or men in the majority is acceptable.
• Subjects are capable of giving informed consent.
• Females capable of bearing children should practice at least one or more of the following methods of contraception for at least one month prior to the and during the study: hormonal, intrauterine device (IUD), or barrier method in combination with a spermicide. Female subjects who are postmenopausal (no menses for greater than one year) or surgically incapable of bearing children may participate.
• Subject should be medication free, other than hormonal birth control, for 48 hours before through 24 hours after completion of study drug administration. If the need for medication is identified during this time period, it will be discussed with and approved by the PI.

Exclusion Criteria:

• Women who are pregnant.
• Women who are breastfeeding.
• Subject has a history of intolerance to IV administration of medication.
• Subject has a known hypersensitivity to baclofen.
• Subject has a significant history of cardiac, neurologic, psychiatric, oncologic, endocrine, metabolic, renal or hepatic disease
• Subject has taken or used any investigational drug or device in the 30 days prior to screening.
• Subject has taken either prescribed or over the counter medication, other than hormonal birth control within 48 hours prior to baclofen administration, unless approved by the Principal Investigator.
• Subject reveals clinically significant abnormalities on screening laboratory tests.
• Subject is a non-English speaker, such that ability to ascertain neurological status would require an interpreter.

Undecided