Major Clinical Manifestation Events and Healthcare Resource Use Among Patients With Long-Chain Fatty Acid Oxidation Disorders (LC-FAOD) Pre- and Post-Triheptanoin Initiation: A Retrospective Claims Database Analysis in the US

OBJECTIVES: Long-chain fatty acid oxidation disorders (LC-FAOD) are a group of rare inborn errors of metabolism that lead to energy depletion and major clinical events (MCEs), including rhabdomyolysis, hypoglycemia, and cardiomyopathy. Current LC-FAOD management strategies include diet and exercise restrictions, avoidance of fasting, and treatment with triheptanoin. This retrospective cohort study assessed MCEs and healthcare resource use (HRU) among commercially insured patients with LC-FAOD treated with triheptanoin.

METHODS: The IQVIA PharMetrics^® Plus database was searched for patients who initiated triheptanoin after FDA approval (30JUN2020) with confirmed LC-FAOD diagnosis, and ≥12 months of continuous insurance enrollment before and ≥6 months after triheptanoin initiation. MCEs were defined as rhabdomyolysis, hypoglycemia, and/or cardiomyopathy in an inpatient and/or emergency room setting identified using ICD-10 Diagnosis Codes. HRU was reported by care setting. MCEs and HRU were assessed up to 18 months before the baseline period and at least 6 months after triheptanoin initiation. Annualized event rates and durations were calculated.

RESULTS: Of 34 triheptanoin-treated patients, 26 (76.5%) were pediatric and 11 (32.4%) were female. 34.6% of pediatrics and 62.5% of adults had rhabdomyolysis, hypoglycemia, and/or cardiomyopathy diagnoses during the baseline period. Before receiving triheptanoin, the annualized average total MCE rate was 0.52 versus 0.23 after triheptanoin initiation. Reductions were observed in all three MCEs: rhabdomyolysis decreased from 0.29 to 0.14, hypoglycemia from 0.06 to 0.00, and cardiomyopathy from 0.22 to 0.10. Annualized average MCE durations decreased from 4.4 to 1.1 days for all MCEs. Annualized average number of hospitalizations was 0.58 before triheptanoin versus 0.31 after triheptanoin initiation. MCE and hospitalization reductions were observed in both pediatric and adult patients.

CONCLUSIONS: This study demonstrated that patients with LC-FAOD experienced fewer MCEs and fewer inpatient visits after receiving triheptanoin. Future studies comparing a no-treatment disease cohort are needed to better understand the triheptanoin treatment effect.