A Pilot Trial of Triheptanoin for People With Amyotrophic Lateral Sclerosis (PALS)

This is an open label, prospective cohort study of 10 people with ALS (PALS) from the Duke ALS Clinic. The first 5 enrolled PALS (Group 1) will receive standard ALS care for the first month, then standard care plus Triheptanoin for the next 5 months. The next 5 enrolled PALS (Group 2) will receive standard ALS care plus Triheptanoin for 6 months (Figure 1). All Group 1 and Group 2 PALS who complete this 6-month study will have an option for Triheptanoin treatment extension for an additional 12 months. In addition to the PALS, there will also be 5 healthy controls enrolled (Group 3), people that do not have ALS or any other neurodegenerative disease). These participants will not receive any treatment; the only outcome measure they will complete is serum and urine biomarker testing at screening/baseline, month 1 and month 6.

The rationale for delaying triheptanoin treatment in one group is to look for differences in MR spectroscopy related to treatment at the 1 month time point. The target triheptanoin dose for this study is 1g/kg/d. This target dose was selected because it was safe and tolerable and altered brain MR spectroscopy in patients with Huntington's Disease. Participants will taper up to this dose as follows: start at 0.25g/kg/d for 1 week, then take 0.5g/kg/d for 1 week, then take 1g/kg/d and stay on this dose for the duration of the study. Triheptanoin will be administered orally with food or by gastrostomy tube over 3 divided doses (breakfast, lunch, and dinner). If at any point after week 1 a participant does not appear to be tolerating their current dose, it will be reduced by 0.25g/kg/d. If they cannot tolerate the starting dose of 0.25g/kg/d, the treatment will be discontinued. A dietician will make contact with all participants every month, either in person or by telephone, to try and maximize compliance.

The primary outcome measure is the ALSFRS-R score obtained monthly for all treated participants (in person at screening/baseline, month 1, month 3 and month 6; via telephone at months 2, 4 and 5). We will also obtain this measure by phone at months 6 and 12 of the extension. For all enrolled PALS in Groups 1 and 2, we will compare the slope of ALSFRS-R progression before enrollment to the slop of ALSFRS-R progression during the trial. ALSFRS-R is a quickly administered (five minute) ordinal rating scale (ratings 0-4) used to determine patients' assessments of their capability and independence in 13 functional activities. All 13 activities are relevant in ALS. Initial validity was established in ALS patients by documenting that their change in ALSFRS-R scores, which correlated with change in strength over time, was closely associated with quality of life measures, and predicted survival. The test-retest reliability is greater than 0.88 for all 13 itemsactivities. The ALSFRS-R declines linearly with time over a wide range during the course of ALS. The minimum clinically significant change in this scale is said to be 20%. The measure can be reliably conducted over the phone.

Secondary outcome measures include:

MR Spectroscopy NAA/Cr ratio in motor cortex will be measured at screening/baseline and 1 month time points. This measure declines over time in patients with ALS. This measure can respond to treatment; it was shown to improve over 3 weeks in patients with ALS on riluzole compared to a group that was not on this treatment. We will compare the MR spectroscopy changes over 1 month in Group 1 to the MR spectroscopy changes over 1 month in Group 2.