This study was a phase 1, randomized, double-blind, placebo-controlled, parallel-group, dose-escalation trial in healthy adults at a single center (Altasciences/Vince and Associates, Overland Park, KS, USA)(Fig. 1). The trial was approved by MidLands Independent Review Board (Overland Park, Kansas) and complied with the International Conference on Harmonisation (ICH)/Good Clinical Practice (GCP) and the ethical principles of the Declaration of Helsinki. All subjects provided written informed consent before any study-related procedure took place. This study adheres to CONsolidated Standards of Reporting Trials (CONSORT) guidelines.
Eligible subjects were healthy adults aged 18–50 years who were willing and able to provide informed consent, had a body mass index of 18–30 kg/m2 and weighed at least 50 kg, agreed to the use of contraception and to refrain from submerging their head fully underwater during the study, and had a physiologic tympanogram classified as Type A (normal).
Subjects were excluded if they: had a history of a significant medical condition; had a clinically significant abnormal olfactory test finding at Screening, defined as a total University of Pennsylvania Smell Identification Test (UPSIT) score < 35 (for females) or < 34 (for males); had a current sleep apnea diagnosis; had a clinically significant ear disorder within 6 weeks; were pregnant or breastfeeding; or had a craniofacial anomaly or a disorder with decreased mucociliary clearance or higher viscosity of the mucus. Subjects were also excluded if they met any of the following criteria prior to Screening: tympanostomy tube placement (within 1 year); upper respiratory tract infection or pharyngitis, allergy or sinus condition or gastroesophageal reflux disease (within 6 weeks); tobacco/nicotine use (within 48 weeks); symptomatic herpes zoster eruptions (within 12 weeks); any malignancy (within 5 years) except for basal or squamous skin carcinomas adequately resected with no signs of metastasis for 3 years; breast cancer (within 10 years); receipt of live vaccine (within 30 days); use of medication (either topically or systemically) for ear or nose disorder (within 12 weeks); use of medication with anticholinergic side effects (within 6 weeks) or vasoconstrictive properties (within 2 weeks); or regular alcohol consumption (within 24 weeks).
Following the Screening period, eligible subjects who consented to participate were admitted to the study center for randomization and were domiciled until 1 day post-treatment (Fig. 1). Subjects had 1 follow-up visit at 5 days post-discharge before exiting the study.
Two dose cohorts, Cohorts A and B, were enrolled. Subjects in each cohort were randomized 4:1 to receive either OP0201 or placebo. Study treatment was administered intranasally by site staff 3 times per day approximately 7 hours apart using a metered dose inhaler and included 2 (Cohort A) or 4 (Cohort B) sprays per nostril at each administration. In the OP0201 groups, subjects received a total dose of 30 mg or 60 mg per day of OP0201 in Cohort A or Cohort B, respectively. Subjects in the placebo group received the same propellant used in OP0201 without any active ingredients. During administration, OP0201 was sprayed directly backwards into each nostril by way of the anterior nostrils towards the lateral wall of the nasal cavity. After all subjects in Cohort A completed 14 days of treatment, a Safety Review Committee assessed blinded safety data to determine if treatment with OP0201 was well tolerated. The Safety Review Committee subsequently recommended escalation to Cohort B. The dose, number of sprays, and dosing interval for this study are expected to exceed those that will be tested in future studies, and thus establish a high safety threshold.
Primary endpoints were adverse events and other safety and tolerability assessments made through otoscopy, tympanometry, nasal and epipharynx endoscopy, the UPSIT, audiology pure-tone hearing testing, physical examination and measurement of vital signs, 12-lead electrocardiography, and clinical laboratory testing. Exploratory endpoints included baseline-adjusted maximum serum concentration (Cmax) of DPPC and CP on Day 14 and time to maximum concentration (tmax) of DPPC and CP on Day 14.
Safety and tolerability assessments
Treatment-emergent adverse events (TEAEs) were defined as AEs that first occurred or worsened in severity after administration of study drug. The relationship of the TEAE to the study medication was evaluated by the Investigator.
Otoscopy, tympanometry, nasal and epipharynx endoscopy, olfactory testing, audiology pure-tone hearing testing, physical examination, measurement of vital signs, electrocardiography, and clinical laboratory testing were performed at various time points throughout the study. Otoscopy was performed to assess the appearance of the tympanic membrane for abnormalities in contour, color, fluid, or translucency. The overall otoscopy assessment was reported as normal or abnormal. Tympanometry was used to evaluate tympanic membrane mobility, Eustachian tube function, and middle ear function. Type A tympanograms were classified as normal; Types B and C were classified as abnormal.12,13 Nasal and epipharynx appearance was assessed via endoscopy and reported as normal or abnormal. The length of the nasal cavity, defined as the distance from the tip of the nose to the entry point of the Eustachian tube, was included in the endoscopic assessments at baseline. The UPSIT was performed to identify potentially clinically significant conditions that could impact participation in the study. The UPSIT consists of 4 booklets, each containing 10 microencapsulated crystal odorants with accompanying multiple-choice smell identification questions.14,15 UPSIT scores less than 35 or 34 were considered abnormal for females and males, respectively. Change from baseline in UPSIT score was captured as a TEAE. An audiology pure-tone hearing test was used to identify clinically significant abnormal hearing. Pure-tone hearing loss was evaluated at 4 frequencies (500, 1000, 2000, and 4000 Hz) with a fail criterion of > 20 dB hearing level at 1 or more frequencies in either ear. Vital signs recorded included sitting systolic and diastolic blood pressure, heart rate, respiration rate, and temperature. Electrocardiograms (ECGs) were collected to ensure that subjects did not have any condition that might present an unacceptable safety risk. Single 12-lead ECGs were collected from subjects in Cohort A; triplicate 12-lead ECGs were collected from subjects in Cohort B using an ECG machine that automatically calculates heart rate and measures PR, QRS, QT, and QTc intervals. With the triplicate 12-lead ECGs, 3 individual ECG tracings were obtained within 4 minutes. Central laboratory assessments included hematology; clinical chemistry; coagulation; viral serology for HIV I and II, HBsAg, and Hepatitis C; and urinalysis.
Blood samples for drug concentration and pharmacokinetic (PK) assessments were taken on Day 1 at 30 and 60 minutes prior to the first dose and Day 14 at 30 minutes prior to and 5, 20, 35, and 50 minutes after the last dose from subjects in Cohort B. Baseline samples collected from subjects were analyzed to establish the endogenous DPPC and CP concentrations, irrespective of treatment allocation.
The sample size was considered adequate to characterize the distribution of the planned endpoints and was not based on statistical considerations. The entered analysis set was defined as all screened subjects who provided informed consent, including subjects who failed screening. The safety analysis set included all subjects who were assigned to a study treatment arm and received at least 1 dose of either OP0201 or placebo. The PK analysis set consisted of all subjects in Cohort B who received at least 1 dose of OP0201 and had at least 1 quantifiable serum DPPC or CP concentration collected post-dose without important protocol deviations/violations or events thought to significantly affect the pharmacokinetics.
No statistical comparisons were conducted between the treatment groups using the safety data. Baseline-corrected DPPC and CP serum levels for each subject were derived by subtracting the observed levels at sample time on Day 14 from the subject’s mean baseline on Day 1 pre-dose. If the resulting value was negative, the estimated baseline-corrected level was set to zero for purposes of reporting and subsequent analysis. The Cmax and tmax were estimated for serum DPPC by noncompartmental methods using actual elapsed time from dosing. PK parameters were summarized by treatment using descriptive statistics, and were derived with Phoenix® WinNonlin® Version 8.0 (Certata, L.P., Princeton, NJ, USA) and/or SAS® Version 9.4 (SAS Institute, Inc., Cary, NC, USA).