Summary
Objective
To investigate the feasibility, safety, and tolerability of add‐on treatment of the triglycerides of heptanoate (triheptanoin) vs the triglycerides of octanoate and decanoate (medium chain triglycerides [MCTs]) in adults with treatment‐refractory epilepsy.
Methods
After an 8‐week prospective baseline period, people with drug‐resistant epilepsy were randomized in a double‐blind fashion to receive triheptanoin or MCTs. Treatment was titrated over 3 weeks to a maximum of 100 mL/d to be distributed over 3 meals and mixed into food, followed by 12‐week maintenance before tapering. The primary aims were to assess the following: (a) safety by comparing the number of intervention‐related adverse events with triheptanoin vs MCT treatment and (b) adherence, measured as a percentage of the prescribed treatment doses taken.
Results
Thirty‐four people were randomized (17 to MCT and 17 to triheptanoin). There were no differences regarding (a) the number of participants completing the study (11 vs 9 participants), (b) the time until withdrawal, (c) the total number of adverse events or those potentially related to treatment, (d) median doses of oils taken (59 vs 55 mL/d, P = 0.59), or (e) change in seizure frequency (54% vs 102%, P = 0.13). Please note that people with focal unaware seizures were underrepresented in the triheptanoin treatment arm (P = 0.04). The most common adverse events were gastrointestinal disturbances (47% and 62.5% of participants). Five people taking on average 0.73 mL/kg body weight MCTs (0.64 mL/kg median) and one person taking 0.59 mL/kg triheptanoin showed >50% reduction in seizure frequency, specifically focal unaware seizures.
Significance
Add‐on treatment with MCTs or triheptanoin was feasible, safe, and tolerated for 12 weeks in two‐thirds of people with treatment‐resistant epilepsy. Our results indicate a protective effect of MCTs on focal unaware seizures. This warrants further study.