Effect of gastric acid-reducing agents on the pharmacokinetics and efficacy of lemborexant

Effect of gastric pH and of a moderate CYP3A4 inducer on the pharmacokinetics of daridorexant, a dual orexin receptor antagonist

AIM

Daridorexant is a dual orexin receptor antagonist developed for the treatment of insomnia. The solubility of daridorexant is pH dependent and daridorexant has been shown to be a sensitive CYP3A4 substrate when co-administered with moderate CYP3A4 inhibitors. The purpose of this study was to assess the effect of an increased gastric pH on daridorexant pharmacokinetics (PK) and the extent of interaction when daridorexant is co-administered with a moderate CYP3A4 inducer.

METHODS

In this prospective, single-centre, randomized, open-label study, 24 male subjects consecutively received four treatments, i.e., daridorexant 50 mg single dose; famotidine 40 mg single dose + daridorexant 50 mg single dose; efavirenz 600 mg once a day (o.d.) during 10 days; and daridorexant 50 mg single dose + efavirenz 600 mg o.d. for 2 days. Plasma PK parameters of daridorexant were derived by noncompartmental analysis. Standard safety and tolerability evaluations were analysed descriptively.

RESULTS

When daridorexant administration was preceded by administration of famotidine, daridorexant C_max decreased by 39%, geometric means ratio (GMR) (90% confidence interval (90% CI)): 0.61 (0.50, 0.73). AUC_0-∞ remained unchanged. In the presence of steady-state efavirenz, daridorexant C_max , AUC_0-∞ , and t_½ decreased by approximately 35% (GMR (90% CI)): 0.65 (0.54, 0.78), 61% (0.39 (0.348, 0.44), and 35% (0.65 (0.58, 0.73), respectively. T_max remained unaffected. All treatments containing daridorexant were well tolerated.

CONCLUSION

Daridorexant 50 mg can be administered concomitantly with gastric pH modifiers or with moderate CYP3A4 inducers without dose adaptation based on efficacy observed at lower doses in Phase 3 studies.

Review of the Efficacy and Safety of Lemborexant, a Dual Receptor Orexin Antagonist (DORA), in the Treatment of Adults With Insomnia Disorder

OBJECTIVE

To provide an overview of the efficacy and safety of lemborexant in the treatment of insomnia disorder by assessing the currently available literature.

DATA SOURCES

A literature search of PubMed was performed (2010 to March 2021) using the following search terms: lemborexant, sleep, orexin.

STUDY SELECTION AND DATA EXTRACTION

All relevant English-language studies were reviewed and considered, with a focus on phase 3 trials.

DATA SYNTHESIS

The efficacy and safety of lemborexant in the treatment of insomnia disorder in adults was demonstrated in 2 phase 3 trials. Lemborexant significantly reduced latency to persistent sleep compared with placebo. The first study also demonstrated a significant reduction compared with the active control zolpidem ER. Somnolence and headache were relatively common, but the marked adverse effects associated with other medications commonly used to treat insomnia, such as cognitive and psychomotor impairment and complex sleep-related behaviors, were not observed.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Although nonpharmacological therapy is considered first-line treatment for insomnia disorder, pharmacological treatment is most commonly utilized. Lemborexant is a viable pharmacological treatment option for patients who are unable to tolerate the adverse effects associated with the most commonly prescribed medications for insomnia, such as benzodiazepines and sedative-hypnotics (Z drugs). This is especially true for geriatric patients, who may be more sensitive to these adverse effects.

CONCLUSION

Lemborexant can be recommended to treat insomnia disorder when pharmacological treatment is warranted. It has demonstrated efficacy in clinical trials and is likely better tolerated than most currently available treatment options.

Physiologically-based pharmacokinetic modeling to predict drug interactions of lemborexant with CYP3A inhibitors

Lemborexant, a recently approved dual orexin receptor antagonist for treatment of adults with insomnia, is eliminated primarily by cytochrome P450 (CYP)3A metabolism. The recommended dose of lemborexant is 5 mg once per night, with a maximum recommended dose of 10 mg once daily. A physiologically-based pharmacokinetic (PBPK) model for lemborexant was developed and applied to integrate data obtained from in vivo drug-drug interaction (DDI) assessments, and to further explore lemborexant interaction with CYP3A inhibitors and inducers. The model predictions were in good agreement with observed pharmacokinetic data and with DDI results from clinical studies with CYP3A inhibitors, itraconazole and fluconazole. The model further predicted that DDI effects of weak CYP3A inhibitors (fluoxetine and ranitidine) are weak, and effects of moderate inhibitors (erythromycin and verapamil) are moderate. Based on the PBPK simulations and clinical efficacy and safety data, the maximum daily recommended lemborexant dose when administered with weak CYP3A inhibitors is 5 mg; co-administration of moderate and strong inhibitors should be avoided except in countries where 2.5 mg has been approved.