A Study of GDC-0134 to Determine Initial Safety, Tolerability, and Pharmacokinetic Parameters in Participants With Amyotrophic Lateral Sclerosis

A Phase I, Double-Blind, Randomized, Placebo-Controlled, Multicenter, Single- and Multiple-Ascending-Dose Study to Determine Initial Safety, Tolerability, and Pharmacokinetics of GDC-0134 in Patients With Amyotrophic Lateral Sclerosis

This first-in-human, double-blind, placebo-controlled Phase I study will be conducted in participants with amyotrophic lateral sclerosis (ALS) to explore safety, tolerability, and pharmacokinetic (PK) properties of GDC-0134. It will include three components: a Single-Ascending-Dose (SAD) stage, a Multiple-Ascending-Dose (MAD) stage, and an Open-Label Safety Expansion (OSE) stage.

Inclusion Criteria:

• Male or female participants with a diagnosis of possible, laboratory-supported probable, probable, or definite ALS according to modified El Escorial criteria
• Upright forced vital capacity of at least 50 percent (%)
• Ability to fast from food for 8 hours prior to dosing and 2 hours after dosing

Exclusion Criteria:

• Currently taking riluzole unless on a stable dose for the 3 months prior to Day -1 and without current liver enzyme or liver function abnormalities
• Currently taking edaravone unless after completion of at least the second 14-day drug-treatment period, as long as Day 1 occurs during a drug-free period at least 24 hours after the last edaravone dose and at least 5 days prior to the first dose of the next cycle
• Positive for hepatitis C antibody, hepatitis B surface antigen, or human immunodeficiency virus (HIV) antibody
• Clinically significant thrombocytopenia
• Currently taking nutritional/herbal supplements, except for over-the-counter vitamins that are within Recommended Dietary Allowance (RDA), unless discontinued at least 7 days prior to Day -1, except upon approval of both the investigator and Sponsor
• For participants participating in a designated drug-drug interaction (DDI) cohort in the MAD stage of the study, who require midazolam/caffeine administration: known allergy, religious prohibition, or other condition limiting midazolam or caffeine administration