Efficacy and safety of Dimdazenil in adults with insomnia disorder: results from a multicenter, randomized, double-blind, placebo-controlled phase III trials.

STUDY OBJECTIVES: To evaluate the efficacy and safety of Dimdazenil, a novel partial positive allosteric modulator for GABAA receptor in adults with insomnia disorder. METHODS: This was a 2-week, multicenter, randomized, double-blind, placebo-controlled, parallel-group phase III study of Dimdazenil. The primary efficacy outcome was total sleep time (TST) analyzed by polysomnography (PSG) on day 13/14. Latency to persistent sleep (LPS), sleep efficiency (SE), and wake after sleep onset (WASO) were analyzed in the same way by polysomnography (PSG). The other secondary outcomes including the average subjective sleep latency (sSL), subjective TST (sTST), subjective SE (sSE), subjective WASO (sWASO), and subjective number of awakenings (sNAW) were analyzed from sleep diary data, and the insomnia severity index (ISI) was also assessed. Treatment-emergent adverse events (TEAEs) were monitored throughout the study. RESULTS: A total of 546 participants with insomnia (age ≥18 years) were randomized (2:1), received treatment with an oral dose of Dimdazenil (2.5 mg) or placebo, and analyzed. Compared to baseline and placebo, Dimdazenil demonstrated significant improvements in PSG measures, increased TST (71.09, 31.68 minutes, respectively; both p < 0.001), increased SE (13.26%, 5.55%, respectively; both < 0.001), reduced WASO (49.67, 20.16 minutes, respectively; both p < 0.001), and reduced LPS (21.65 minutes, p < 0.001; 6.46 minutes, p = 0.023). Compared to placebo, Dimdazenil also improved key self-reported measures of sTST (18.33 minutes, p < 0.001), sWASO (14.60 minutes, p < 0.001), sSL (4.23 minutes, p < 0.001), sSE (2.97%, p < 0.001), and sNAW (0.29, p < 0.001). Participants treated with Dimdazenil reported a significant improvement in ISI. Dimdazenil was well tolerated. The majority of TEAEs were mild or moderate. There were no clinically relevant treatment-related serious AEs and no deaths. CONCLUSIONS: Dimdazenil of 2.5 mg provided significant benefit on sleep maintenance and sleep onset in individuals with insomnia disorder versus placebo, with a favorable safety profile and was well tolerated. CLINICAL TRIAL INFORMATION: A multicenter, randomized, double-blind phase III clinical study evaluating the efficacy and safety of EVT201 capsules compared to placebo in patients with insomnia disorders (http://www.chinadrugtrials.org), with the number of CTR20201068.

Simultaneous quantification of EVT201, a novel partial positive allosteric GABAA receptor modulator, and its two metabolites in human plasma by UHPLC/MS/MS.

A sensitive, accurate and rapid UHPLC-MS/MS method was developed and validated for the simultaneous determination of EVT201 and its two metabolites, Ro46-1927 and Ro18-5528, in human plasma. D6-EVT201 was used as the internal standard (IS). Plasma samples were extracted using ethyl acetate after being alkalized with saturated sodium carbonate solution. Chromatographic separation was carried out on an Acquity BEH C18 column (2.1 × 50 mm, 1.7 µm) with a gradient mobile phase at a flow-rate of 0.50 mL/min. The analytical run time was 5.5 min. For mass spectrometric detection, multiple reaction monitoring (MRM) was used. The MRM ion transitions were m/z 373.2 → 58.0 for EVT201, m/z 359.2 → 316.1 for Ro46-1927, m/z 291.2 → 274.1 for Ro18-5528 and m/z 379.3 → 64.0 for the IS. The linear range was 0.2-200 ng/mL for each analyte, with a correlation coefficient (r) over 0.9900. The intra-/inter- precision was within 7.9% and 4.5% for EVT201, 13.2% and 6.3% for Ro46-1927, 3.7% and 4.1% for Ro18-5528. For the accuracy, the relative bias of intra-/inter- run was no more than 6.4% and 4.6% for EVT201, 9.4% and 7.9% for Ro46-1927, -6.9% and -7.5% for Ro18-5528. The validated method was successfully applied to the analysis of more than 1500 samples from a Phase I clinical trial. The incurred sample reanalysis (ISR) of 146 samples from the study was evaluated and the results met the acceptance criteria. It indicated that the method could be used for the pharmacokinetic study of EVT201.