Ensifentrine

Ensifentrine systemic exposure increased by 2.3-fold in subjects with moderate or severe hepatic impairment compared with healthy subjects. Use ensifentrine with caution in patients with hepatic impairment.

Patients with severe renal impairment have not been evaluated.

Before initiating treatment with ensifentrine, healthcare providers should carefully weigh the risk and benefits of treatment with ensifentrine in patients with a history of depression and/or suicidal thoughts or behavior. Healthcare providers should carefully evaluate the risks and benefits of continuing treatment with ensifentrine if such events occur.

Risk Summary

There are no available data on ensifentrine use in pregnant women to evaluate for a drug-associated risk of major birth defects, miscarriage or other adverse maternal or fetal outcomes. In animal reproduction studies, administration of inhaled ensifentrine at exposures 30 times the exposure at the maximum recommended human daily inhalation dose (MRHDID) to male rats for 10 weeks prior to mating with untreated females produced increased pre- and post- implantation loss, and decreased live embryos in untreated female rats. No adverse developmental effects were observed with inhalation administration of ensifentrine to pregnant rats and rabbits during organogenesis at maternal exposures up to 79 and 9 times the exposure at MRHDID, respectively. No adverse developmental effects were observed after inhaled administration of ensifentrine to pregnant rats from the period of organogenesis through lactation at exposures up to approximately 79 times the MRHDID (see Data).

The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.

Data

Animal Data

In a male fertility study, ensifentrine was administered to male rats at inhalation doses of 2, 6, and 16 mg/kg/day (4, 13, and 30 times the exposure at the MRHDID) for 10 weeks prior to mating to untreated females. Adverse effects at 16 mg/kg/day (30 times the exposure at the MRHDID) on reproductive performance included increased pre- and post- implantation loss, and decreased live embryos per litter in untreated females. No developmental toxicity was observed in rats at 6 mg/kg/day (13 times the exposure at the MRHDID).

In an embryo-fetal development study, pregnant rats were administered ensifentrine at inhalation doses of up to 15 mg/kg/day (79 times the exposure at the MRHDID) during the period of organogenesis from gestation Days 6 to 17. Ensifentrine did not cause adverse effects to the fetus at exposures up to 79 times the MRHDID (on an AUC basis at a maternal inhalation dose of 15 mg/kg/day).

In an embryo-fetal development study, pregnant rabbits were administered ensifentrine at inhalation doses of up to 12 mg/kg/day (9 times the exposure at the MRHDID) during the period of organogenesis from gestation Days 6 to 19. Ensifentrine did not cause adverse effects to the fetus at maternal exposures up to 9 times the MRHDID.

In a pre- and post-natal development (PPND) study, pregnant rats were administered ensifentrine at inhalation doses of up to 19 mg/kg/day (approximately 79 times the exposure at the MRHDID) from gestation day 6 to lactation/post-partum day 24. No adverse effects were observed in the offspring exposed daily from birth (in utero) through lactation at maternal pulmonary deposited doses up to approximately 79 times the MRHDID.

There are no data on the presence of ensifentrine in human milk, the effects on the breastfed child, or the effects on milk production. There are no data from animal studies on the presence of ensifentrine in milk.

The developmental and health benefits of breastfeeding should be considered along with the mother’s clinical need for ensifentrine and any potential adverse effects on the breastfed child from ensifentrine or from the underlying maternal condition.

A two-year inhalation study in Han Wistar rats and a 6-month oral study in Tg.rasH2 transgenic mice were conducted to assess the carcinogenic potential of ensifentrine. No evidence of tumorigenicity was observed in male and female rats at an exposure approximately 40 times the MRHDID. No evidence of tumorigenicity was observed in male and female Tg.rasH2 mice at oral doses up to 80 mg/kg/day, the highest dose tested.

Ensifentrine was negative for genotoxicity in the following assays: in vitro Ames test for bacterial gene mutation, in vivo comet test with rats, or in vivo micronucleus assay with mice.

In a male fertility study, ensifentrine was administrated to male rats at inhalation doses of 2, 6, and 16 mg/kg/day (4, 13, and 30 times the exposure at the MRHDID) for 10 weeks prior to mating to untreated females. Male rats had decreased sperm motility and increased abnormal sperm morphology at an inhalation dose of 16 mg/kg/day (approximately 30 times the exposure at the MRHDID). Decreased sperm counts in the testis were observed at all doses. Atrophy/degeneration in the testis and intraluminal germ cell debris in the epididymis were observed at doses of 6 (13 times the exposure at the MRHDID) and 16 mg/kg/day (30 times the exposure at the MRHDID). Additional adverse effects at 16 mg/kg/day on reproductive performance included decreased mating index and decreased fertility index. The sperm counts, sperm motility, and sperm morphology were reversible at the end of a 4-week treatment-free period. Atrophy/degeneration in the testis and intraluminal germ cell debris in the epididymis were not present at the end of a 4-week treatment-free period. In a female fertility study, ensifentrine was administrated to female rats at inhalation doses of up to 18 mg/kg/day from two weeks prior to mating to 7 days after mating. Ensifentrine had no effect on female fertility and reproductive performance indices up to 18 mg/kg/day (31 times the exposure at the MRHDID).

• Paradoxical Bronchospasm
• Psychiatric Events Including Suicidality

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The safety of ensifentrine was based on the pooled safety population from two randomized, double-blind, placebo-controlled trials (ENHANCE-1 and ENHANCE-2) for 24 weeks, and a 48-week cohort that assessed safety in ENHANCE-1. In these trials, a total of 975 patients received 3 mg of ensifentrine twice daily administered by oral inhalation using a standard jet nebulizer. The safety population included all patients who were randomized and received at least one dose of ensifentrine or placebo.

Adverse reactions that occurred at an incidence greater than or equal to 1% in ensifentrine and were more common than placebo in the pooled population are provided in Table 1.

The proportion of patients who discontinued treatment due to adverse reactions was 7.6% for the ensifentrine-treated patients and 8.2% for placebo-treated patients.

Table 1. Adverse Reactions with Ensifentrine with incidence >1% and More Common than Placebo in Patients with COPD in the Pooled 24-Week Safety Population (ENHANCE-1 and ENHANCE-2):

Adverse Reactions in the 48-Week Cohort

In the 48-week cohort of ENHANCE-1, 369 patients were enrolled to be treated with 3 mg ensifentrine (N=280) or placebo (N=89) twice daily for 48 weeks. The adverse reactions reported in the 48-week cohort were consistent with those observed in the pooled 24-week safety population.