Healthy VolunteerPhase 1NCT05567367
A Healthy Volunteer Study Evaluating the the Safety, Tolerability, and Pharmacokinetics of RT234
A Phase 1 study testing Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) and Vardenafil Oral Tablet in people with Healthy Volunteer, run by Respira Therapeutics, Inc. at 1 site in Australia.
Trial summary
The objective of this two part study was to demonstrate safety, tolerability, and pharmacokinetics of RT234 in healthy volunteers. This study is also known as Vardenafil Inhaled for Pulmonary Arterial Hypertension PRN Phase 1 (VIPAH-PRN 1) study Read more about this study
- Who is it for?
- Ages 18 to 45 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Volunteer
- What is being tested?
- Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) and Vardenafil Oral Tablet
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 31 participants
- Where
- 1 siteAustralia
- Study dates
- 31 Jul 2018to 4 Dec 2019
- Phase
- Phase 1
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 45 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy male or female, 18 to 45 years of age (inclusive at time of informed consent)
- Normal heart, lung, kidney, and liver function based on physical examination
- Systolic blood pressure of 100-145 mmHg, diastolic blood pressure of 50-90 mmHg, and a resting heart rate of 40-100 bpm at Screening
- A body mass index (BMI) of ≤18 to ≥30 kg/m2 at Screening
- Must be a non-smoker or ex-smoker with less than a 5-pack year history of smoking (including the use of electronic cigarettes) and have ceased smoking ≥1 year prior to Screening; or a social smoker (defined as less than 10 cigarettes in the previous 12 months)
Who cannot join
- Has serum transaminase (i.e., alanine aminotransferase [ALT], aspartate aminotransferase [AST], or gamma-glutamyl transferase [GGT]) levels greater than three times the upper level of normal
- Abnormal orthostatic vital signs (at screening) defined as a decrease of ≥20 mmHg in systolic blood pressure and/or a decrease of ≥10 mmHg in diastolic blood pressure and/or >25 bpm increase in heart rate within 3 minutes of standing, or with symptoms of light-headedness, dizziness, or fainting upon standing.
- History of hypotension including fainting, syncope, orthostatic hypotension, and/or vasovagal reactions
- History of retinitis pigmentosa
- Vision loss due to non-arteritic anterior ischemic optic neuropathy (NAION) or other optic perfusion impairment
- History of priapism or anatomical deformation of the penis
Show all 11Show fewer
- History of sudden sensorineural hearing loss (SSHL), need for hearing aids, and/or other documented hearing loss
- A corrected QT interval using Fridericia's formula (QTcF) >450 msec
- Has evidence of significant obstructive lung disease on spirometry. Subjects with any of the following criteria will be excluded:
- FEV1 <60% (predicted) (pre-bronchodilators); or
- FEV1/FVC <65% (pre-bronchodilators)
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Phase 1, Two-Part, Single-Center, Open-Label, Randomized, Cross-Over, Single Ascending Doses (SAD), Followed by a Multiple Ascending Doses (MAD) Safety and Pharmacokinetic Study of RT234 in Healthy Subjects
The objective of this two part study was to demonstrate safety, tolerability, and pharmacokinetics of RT234 in healthy volunteers.
This study is also known as Vardenafil Inhaled for Pulmonary Arterial Hypertension PRN Phase 1 (VIPAH-PRN 1) study
Read the detailed description
This study was designed to evaluate safety and tolerability and to characterize the PK profiles of single and repeated doses of inhaled vardenafil as RT234. In addition, vardenafil PK after single 0.6 mg doses of RT234 was compared to that following administration of a single 20 mg dose of oral vardenafil tablets.
- Conditions
- Healthy Volunteer
- Being tested
- Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI), Vardenafil Oral Tablet
- Keywords
- Pulmonary Arterial Hypertension, Familial Primary Pulmonary Hypertension, Vascular Diseases, Cardiovascular Diseases, Hypertension, Pulmonary, Lung Diseases, Respiratory Tract Diseases, Vardenafil Dihydrochloride, Inhaled Vardenafil, Vasodilator Agents, Phosphodiesterase 5 Inhibitors, Phosphodiesterase Inhibitors, Enzyme Inhibitors, Molecular Mechanisms of Pharmacological Action
- Medical subject headings
- Pulmonary Arterial Hypertension, Familial Primary Pulmonary Hypertension, Vascular Diseases, Cardiovascular Diseases, Hypertension, Pulmonary, Lung Diseases, Respiratory Tract Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Combination product
Also called vardenafil inhalation powder
RT234 is a drug/device combination product composed of vardenafil hydrochloride as the drug constituent and will utilize RS01 DPI device.
Vardenafil Oral TabletDrug
Also called Levitra
20 mg oral vardenafil tablet.
| Study group | Role | What they receive |
|---|---|---|
| RT234 0.2 mg, Single Ascending Dose (SAD) | Experimental | Part 1, SAD Cohort 1A Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) |
| RT234 0.6 mg followed by oral vardenafil 20mg on day 3, SAD | Experimental | Part 1, SAD Cohort 2A1 Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI); Drug: Vardenafil Oral Tablet |
| Oral vardenafil 20mg followed by RT234 0.6 mg on day 3, SAD | Experimental | Part 1, SAD Cohort 2A2 Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI); Drug: Vardenafil Oral Tablet |
| RT234 1.2 mg, SAD | Experimental | Part 1, SAD Cohort 3A Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) |
| RT234 2.4 mg, SAD | Experimental | Part 1, SAD Cohort 4A Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) |
| RT234 2.4 mg, Multiple Ascending Dose (MAD) | Experimental | Part 2, MAD Cohort 1B Receives: Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Number of participants with treatment related adverse events as assessed by CTCAE v5.0
Adverse events reported by participants and those observed by the investigator in relation to laboratory tests, vital signs, ECGs, medications used to treat adverse events, and physical examinations were analyzed.
Measured: Up to to 10 days
Secondary outcomes (7)
Peak plasma concentration (Cmax)
Cmax was measured for 4 single doses of oral vardenafil.
Measured: Up to 10 days
Time to reach maximum concentration (Tmax)
Tmax was measured for 4 single doses of oral vardenafil.
Measured: Up to 10 days
Area under the curve (AUC)
AUC was measured for 4 single doses of RT234
Measured: Up to 10 days
Half life (t1/2)
t1/2 was measured for 4 single doses of RT234
Measured: Up to 10 days
Terminal elimination rate constant (Kel)
Kel was measured for 4 single doses of RT234
Measured: Up to 10 days
Total body clearance (CL/F)
CL/F was measured for 4 single doses of RT234
Measured: Up to 10 days
Total volume of distribution at the terminal phase
measured for 4 single doses of RT234
Measured: Up to 10 days
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted5 Oct 2022
- Study start31 Jul 2018
- Primary completion4 Dec 2019
- Study completion4 Dec 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for Healthy VolunteerStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 1
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Enrolment
- 31 participants (actual)
Sponsor and investigators
- Lead sponsor
- Respira Therapeutics, Inc.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
- Investigators
- Donna Jarlenski, MS, Study director, Respira Therapeutics
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT05567367
- Sponsor's protocol ID
- RT234-CL101
- Other IDs
- ACTRN12618001077257
- Status last verified
- Sep 2025
- First submitted
- 4 Apr 2022
- Last updated
- 22 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- Yes
- Individual data sharing
- No
Publications
Eldon MA, Parsley EL, Maurer M, Tarara TE, Okikawa J, Weers JG. Safety, Tolerability, and Pharmacokinetics of RT234 (Vardenafil Inhalation Powder): A First-in-Human, Ascending Single- and Multiple-Dose Study in Healthy Subjects. J Aerosol Med Pulm Drug Deliv. 2021 Aug;34(4):251-261. doi: 10.1089/jamp.2020.1651. Epub 2020 Dec 15.
PubMed 33325799
Study at a glance
From the registry record, last updated by the sponsor on 22 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase 1, Two-Part, Single-Center, Open-Label, Randomized, Cross-Over, Single Ascending Doses (SAD), Followed by a Multiple Ascending Doses (MAD) Safety and Pharmacokinetic Study of RT234 in Healthy Subjects
- ClinicalTrials.gov ID
- NCT05567367
- Acronym / sponsor ID
- RT234-CL101
- Conditions
- Healthy Volunteer
- Keywords
- Pulmonary Arterial Hypertension, Familial Primary Pulmonary Hypertension, Vascular Diseases, Cardiovascular Diseases, Hypertension, Pulmonary, Lung Diseases, Respiratory Tract Diseases, Vardenafil Dihydrochloride
- Phase
- Phase 1
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 31 participants (actual)
- Lead sponsor
- Respira Therapeutics, Inc.Industry (pharma, biotech, devices)
- Study start
- 31 Jul 2018 (actual)
- Primary completion
- 4 Dec 2019 (actual)
- Study completion
- 4 Dec 2019 (actual)
- First posted
- 5 Oct 2022 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The objective of this two part study was to demonstrate safety, tolerability, and pharmacokinetics of RT234 in healthy volunteers.
This study is also known as Vardenafil Inhaled for Pulmonary Arterial Hypertension PRN Phase 1 (VIPAH-PRN 1) study
Detailed description
This study was designed to evaluate safety and tolerability and to characterize the PK profiles of single and repeated doses of inhaled vardenafil as RT234. In addition, vardenafil PK after single 0.6 mg doses of RT234 was compared to that following administration of a single 20 mg dose of oral vardenafil tablets.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 6
| Arm | Type | Receives |
|---|---|---|
| RT234 0.2 mg, Single Ascending Dose (SAD) | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Part 1, SAD Cohort 1A |
| RT234 0.6 mg followed by oral vardenafil 20mg on day 3, SAD | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI), Drug: Vardenafil Oral TabletPart 1, SAD Cohort 2A1 |
| Oral vardenafil 20mg followed by RT234 0.6 mg on day 3, SAD | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI), Drug: Vardenafil Oral TabletPart 1, SAD Cohort 2A2 |
| RT234 1.2 mg, SAD | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Part 1, SAD Cohort 3A |
| RT234 2.4 mg, SAD | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Part 1, SAD Cohort 4A |
| RT234 2.4 mg, Multiple Ascending Dose (MAD) | Experimental | Combination Product: Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Part 2, MAD Cohort 1B |
Who may qualify
- Ages
- 18 to 45 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (5 listed)
- Healthy male or female, 18 to 45 years of age (inclusive at time of informed consent)
- Normal heart, lung, kidney, and liver function based on physical examination
- Systolic blood pressure of 100-145 mmHg, diastolic blood pressure of 50-90 mmHg, and a resting heart rate of 40-100 bpm at Screening
- A body mass index (BMI) of ≤18 to ≥30 kg/m2 at Screening
- Must be a non-smoker or ex-smoker with less than a 5-pack year history of smoking (including the use of electronic cigarettes) and have ceased smoking ≥1 year prior to Screening; or a social smoker (defined as less than 10 cigarettes in the previous 12 months)
Key exclusion criteria (11 listed)
- Has serum transaminase (i.e., alanine aminotransferase [ALT], aspartate aminotransferase [AST], or gamma-glutamyl transferase [GGT]) levels greater than three times the upper level of normal
- Abnormal orthostatic vital signs (at screening) defined as a decrease of ≥20 mmHg in systolic blood pressure and/or a decrease of ≥10 mmHg in diastolic blood pressure and/or >25 bpm increase in heart rate within 3 minutes of standing, or with symptoms of light-headedness, dizziness, or fainting upon standing.
- History of hypotension including fainting, syncope, orthostatic hypotension, and/or vasovagal reactions
- History of retinitis pigmentosa
- Vision loss due to non-arteritic anterior ischemic optic neuropathy (NAION) or other optic perfusion impairment
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI)Also: vardenafil inhalation powderRT234 is a drug/device combination product composed of vardenafil hydrochloride as the drug constituent and will utilize RS01 DPI device. | Combination product | Oral vardenafil 20mg followed by RT234 0.6 mg on day 3, SAD, RT234 0.2 mg, Single Ascending Dose (SAD), RT234 0.6 mg followed by oral vardenafil 20mg on day 3, SAD, RT234 1.2 mg, SAD, RT234 2.4 mg, Multiple Ascending Dose (MAD), RT234 2.4 mg, SAD |
| Vardenafil Oral TabletAlso: Levitra20 mg oral vardenafil tablet. | Drug | Oral vardenafil 20mg followed by RT234 0.6 mg on day 3, SAD, RT234 0.6 mg followed by oral vardenafil 20mg on day 3, SAD |
Primary outcome
Number of participants with treatment related adverse events as assessed by CTCAE v5.0
Time frame: Up to to 10 days
Adverse events reported by participants and those observed by the investigator in relation to laboratory tests, vital signs, ECGs, medications used to treat adverse events, and physical examinations were analyzed.
7 secondary outcomes
Peak plasma concentration (Cmax)
Time frame: Up to 10 days
Time to reach maximum concentration (Tmax)
Time frame: Up to 10 days
Area under the curve (AUC)
Time frame: Up to 10 days
Half life (t1/2)
Time frame: Up to 10 days
Terminal elimination rate constant (Kel)
Time frame: Up to 10 days
Total body clearance (CL/F)
Time frame: Up to 10 days
Total volume of distribution at the terminal phase
Time frame: Up to 10 days
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 22 Sep 2025.
- Results publication: PubMed 33325799Eldon MA, Parsley EL, Maurer M, Tarara TE, Okikawa J, Weers JG. Safety, Tolerability, and Pharmacokinetics of RT234 (Vardenafil Inhalation Powder): A First-in-Human, Ascending Single- and Multiple-Dose Study in Healthy Subjects. J Aerosol Med Pulm Drug Deliv. 2021 Aug;34(4):251-261. doi: 10.1089/jamp.2020.1651. Epub 2020 Dec 15.
- Individual participant dataSharing planned: No
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Healthy Participants
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Donna Jarlenski, MS study director
Respira Therapeutics
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 1 study testing Drug: RT234 - vardenafil inhalation powder; Device: RS01 dry powder inhaler (RS01 DPI) and Vardenafil Oral Tablet in people with Healthy Volunteer, run by Respira Therapeutics, Inc. at 1 site in Australia.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 11 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 22 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Australia. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Number of participants with treatment related adverse events as assessed by CTCAE v5.0 (time frame: Up to to 10 days). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT05567367, which also lists 1 linked publication.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 22 Sep 2025.