Libertas: a phase II placebo-controlled study of NRL001 in patients with faecal incontinence showed an unexpected and sustained placebo response.

PURPOSE: Faecal incontinence (FI) is distressing, significantly reduces quality of life (QoL) and has few pharmacological treatments. The α1-adrenoceptor agonist NRL001 (1R,2S-methoxamine hydrochloride) improves anal sphincter tone. NRL001 efficacy was evaluated by changes in Wexner scores at week 4 vs. baseline in NRL001-treated patients compared with placebo. Impact of NRL001 on QoL and safety were also assessed. METHODS: Four hundred sixty-six patients received NRL001 (5, 7.5 or 10 mg) or placebo as suppository, once daily over 8 weeks. Wexner score, Vaizey score and QoL were analysed at baseline, week 4 and week 8. FI episodes and adverse events were recorded in diaries. RESULTS: At week 4, mean reductions in Wexner scores were -3.0, -2.6, -2.6 and -2.4 for NRL001 5, 7.5, 10 mg and placebo, respectively. All reduced further by week 8. As placebo responses also improved, there was no significant treatment effect at week 4 (p = 0.6867) or week 8 (p = 0.5005). FI episode frequency improved for all patients, but not significantly compared with placebo (week 4: p = 0.2619, week 8: p = 0.5278). All patients' QoL improved, but not significantly for all parameters (p > 0.05) except depression/self-perception at week 4 (p = 0.0102) and week 8 (p = 0.0069), compared with placebo. Most adverse events were mild and judged probably or possibly related to NRL001. CONCLUSIONS: All groups demonstrated improvement in efficacy and QoL compared with baseline. NRL001 was well-tolerated without serious safety concerns. Despite the improvement in all groups, there was no statistically significant treatment effect, underlining the importance of relating results to a placebo arm.

Randomised clinical trial: study of escalating doses of NRL001 given in rectal suppositories of different weights.

AIMS: The application of α-adrenoceptor agonists can improve faecal incontinence symptoms. The aim of this study was to investigate the pharmacokinetic and systemic effects of NRL001 administered as different strengths in 1 or 2 g suppositories. METHODS: This randomised, double-blind, placebo controlled study included 48 healthy subjects. Group 1 consisted of two cohorts of 12 subjects administered either four single doses of 1 or 2 g rectal suppository with either 5, 7.5 or 10 mg NRL001, or matching placebo. Group 2 consisted of two cohorts of 12 subjects administered either four single doses of 1 or 2 g rectal suppository with either 10, 12.5 or 15 mg NRL001, or matching placebo. Doses were given in an escalating manner with placebo at a random position within the sequence. RESULTS: Tmax was at ~4.5 h post-dose for all NRL001 doses. Median AUC0-tz , AUC0-∞ and Cmax increased with increasing dose for both suppository sizes. The estimate of ratios of geometric means comparing 2 g with 1 g suppository, and regression analysis for dose proportionality, was close to 1 for the variables AUC0-tz , AUC0-∞ and Cmax (P > 0.05). For both suppository sizes, 20-min mean pulse rate was significantly decreased compared with placebo with all doses (P < 0.05). Blood pressure decreased overall. There were 144 adverse events (AEs) and no serious AEs reported during the study. All AEs were mild in severity. CONCLUSIONS: The regression analysis concluded that the doses were dose proportional.

Meta-analysis for cardiovascular effects of NRL001 after rectal application in healthy volunteers.

AIMS: NRL001 is a highly specific α1 -adrenoceptor agonist currently under evaluation for the treatment of faecal incontinence caused by a weak internal anal sphincter. The aim of this meta-analysis was to quantify the effect of NRL001 on cardiovascular parameters including heart rate, blood pressure and QT interval. METHODS: Data from the four Phase I healthy volunteer studies SUM (NCT00857467), SURD (NCT01099670), SUSD (NCT00850590) and SAGE (NCT01099683) were pooled and analyses were performed on individual subject data. Mixed effects regression analysis was used to determine the effect of NRL001 on heart rate, blood pressure and QT intervals. A multivariate statistical model was used to determine the effect of covariates on heart rate. RESULTS: Subjects given NRL001 experienced a dose related decrease in heart rate of up to 9.48 bpm compared with subjects in the placebo arms. No statistically significant evidence for a threshold effect was found. There was no clear evidence of dose effect of NRL001 on blood pressure. QT interval increased in all NRL001 subject as expected; QTC F also showed a statistically significant increase. However, QTC B was shortened with no significant treatment effect. CONCLUSIONS: NRL001 was found to have a dose-dependent effect on heart rate; however clinically-relevant bradycardia was not reported, indicating the decrease in heart rate was not of clinical significance. Furthermore, no clinically-significant drug effect on blood pressure or mean arterial pressure was observed. QT intervals were affected by changes in heart rate. However, trends were dependant on the correction factor used. No consistent QT effect was observed, but a thorough QTC study will be required to confirm the effects of rectally applied NRL001.

A randomised, controlled, crossover study to investigate the pharmacodynamics, pharmacokinetics and safety of 1R,2S-methoxamine hydrochloride (NRL001) in healthy elderly subjects.

AIMS: This study aimed to assess the effects of a single dose of 10 mg NRL001 (the 1R,2S stereoisomer of methoxamine hydrochloride) in a 2 g suppository on pharmacodynamic and pharmacokinetic (PK) variables, and safety, in a healthy elderly population. METHODS: This was a Phase I, single-centre, randomised, double-blind, placebo-controlled crossover study during which subjects received a single 2 g suppository of 10 mg NRL001 and a matching placebo in two separate treatment periods. The main outcome measures were Holter-, vital signs- and electrocardiogram-derived cardiovascular variables; plasma PK analysis; and safety assessments. RESULTS: Twenty-six subjects were dosed with study medication. Statistically significant reductions in Holter-derived heart rate (HR), vital signs-derived HR and diastolic blood pressure (BP) were observed comparing NRL001 with placebo treatment, and also with increasing NRL001 plasma concentration. No statistically significant relationships were observed between NRL001 concentration and systolic BP, mean arterial pressure or QTC interval (both Bazett's and Fridericia's correction). Thirty-nine adverse events were reported in 20 (76.9%) subjects, mostly after dosing with NRL001. CONCLUSION: Administration of NRL001 suppositories led to decreases in HR when compared with placebo data. NRL001 was well tolerated with a good safety profile during the study. Healthy elderly subjects did not show significantly different biological responses to NRL001 suppositories compared with younger healthy volunteers in previous studies.

A double-blind, placebo-controlled, randomised, parallel-group, dose-escalating, repeat dose study in healthy volunteers to evaluate the safety, tolerability, pharmacodynamic effects and pharmacokinetics of the once daily rectal application of NRL001 suppositories for 14 days.

AIMS: The 1R,2S stereoisomer of methoxamine hydrochloride, NRL001, is a highly selective α1-adrenoceptor agonist being developed for the local treatment of non-structural faecal incontinence caused by weak internal anal sphincter tone. This study investigated the steady state pharmacokinetics (PK) and safety of 2 g rectal suppositories containing NRL001 in different strengths (7.5, 10, 12.5 or 15 mg). METHODS: Healthy volunteers aged 18-45 years received 14 daily doses of NRL001 2 g suppositories or matching placebo. In each dose group nine participants received NRL001 and three received placebo. Blood samples to determine NRL001 concentrations were taken on Days 1, 7 and 14. Cardiovascular parameters were collected via electrocardiograms, Holter monitoring (three lead Holter monitor) and vital signs. RESULTS: Forty-eight volunteers were enrolled; 43 completed the study and were included in the PK analysis population. AUC and Cmax broadly increased with increasing dose, Tmax generally occurred between 4.0 and 5.0 h. Although the data did not appear strongly dose proportional, dose proportionality analysis did not provide evidence against dose proportionality as the log(dose) coefficients were not significantly < 1. NRL001 did not accumulate over time for any dose. Increasing NRL001 concentrations were related to changes in vital sign variables, most notably decreased heart rate. The most commonly reported adverse events (AEs) in the active treatment groups were paraesthesia and piloerection. CONCLUSIONS: Treatment with NRL001 was generally well tolerated over 14 days once daily dosing and plasma NRL001 did not accumulate over time. Treatment was associated with changes in vital sign variables, most notably decreased heart rate. AEs commonly reported with NRL001 treatment were events indicative of a systemic α-adrenergic effect.

A randomised, controlled, crossover study to investigate the safety and response of 1R,2S-methoxamine hydrochloride (NRL001) on anal function in healthy volunteers.

AIMS: This study aimed to assess the dose and volume effects of suppository preparations and safety of NRL001 (one of four possible stereoisomers of methoxamine hydrochloride) on anal sphincter tone using rectal suppositories in healthy adult volunteers. METHODS: This was a Phase I, single-centre, randomised, double-blind, three-way crossover study during which subjects received three single doses of 1 g rectal suppositories (containing 5 or 10 mg NRL001 or matching placebo) or 2 g rectal suppositories (containing 10 or 15 mg NRL001 or matching placebo) on three separate dosing days. The outcome measures were mean anal resting pressure (MARP) variables (monitored continuously for 20-30 min before and up to 6 h after dosing), pharmacokinetics (PK) and safety assessments. RESULTS: Twenty-six subjects were dosed with study medication. Two subjects were withdrawn prematurely and were not included in the main analysis. There was a dose-dependent increase in anal sphincter tone (MARP) when comparing the 5 and 10 mg doses of NRL001; however, the 15 mg dose did not have a significantly greater effect than the 10 mg dose. Suppository size (1 or 2 g) did not appear to have an effect on sphincter tone. There was no evidence against dose proportionality for the PK variables, but the mean maximum plasma concentration (Cmax ) for the 1 g suppository group was higher than for the 2 g group. Twenty-one adverse events were reported in 8 (30.8%) subjects. A dose dependent decrease in heart rate was noted; however, there were no adverse events reported that were related to this reduction in heart rate. CONCLUSIONS: The increase in anal sphincter tone supports the potential therapeutic use of NRL001 in treating faecal incontinence, with further studies in patients required. NRL001 was well tolerated in single doses of up to 15 mg.