A Phase 2 interventional study of ALT-100 mAb and ALT-100 (Placebo) in Acute Respiratory Distress Syndrome (ARDS), sponsored by Aqualung Therapeutics Corp.. Active, not recruiting at 1 site in United States. Open to participants aged 18 Years to 100 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-10-23.
Sponsored by Aqualung Therapeutics Corp. · Phase 2, Interventional, and Treatment
A Phase 2a, multi-center, randomized, double-blind, placebo-controlled study to assess the efficacy and safety of ALT-100mAb in patients with moderate to severe ARDS.
PUERTA is a Phase 2a, randomized, double-blind, placebo-controlled study in adults with moderate to severe ARDS consequent to sepsis, septic shock, trauma, and/or bacterial or viral pneumonia who have been hospitalized. The safety and tolerability, PK, preliminary efficacy, and PD of a single infusion of ALT-100 mAb will be assessed. All participants will receive study drug within 12 hours of their ARDS diagnosis and within 4 hours of initiation of MV (mechanical ventilation).
It is planned that 90 eligible participants will be randomized at a 2:1 ratio to receive a single dose of either ALT-100 mAb or placebo via IV infusion at the time the diagnosis of moderate to severe ARDS is confirmed. An additional 9 participants may be randomized if an optional cohort of low or intermediate ALT-100 mAb dose is enrolled.
The study will be conducted in 2 parts:
Dose Escalation (Part A) Part A will assess 2 doses of ALT-100 mAb in sequentially enrolled cohorts of up to 9 participants in each cohort. The planned doses of ALT-100 mAb are 0.4 mg/kg (Cohort 1a) and 1.0 mg/kg (Cohort 2a).
Dose Expansion (Part B) Following SRC review of all data up to Day 29 from the 9 participants in each cohort in Part A, additional participants (up to 36 per dose cohort) may be enrolled into 2 dose expansion cohorts, the dose of which will be determined by the SRC. Part B will further explore the safety, preliminary efficacy, PK, and systemic biomarker profile of ALT-100 mAb.
Participants enrolled in Part A may not be re-enrolled in Part B.
The screening, Treatment, and Safety Follow-up schedules are the same for Part A (dose escalation) and Part B (dose expansion) cohorts.
1,596 studies on the registry are indexed under Respiratory Distress Syndrome; 312 are open to participants now.
This study's enrollment of 15 is below the median of 60 across 960 interventional studies indexed under Respiratory Distress Syndrome.
Browse Respiratory Distress Syndrome studies →Aqualung Therapeutics Corp. is the lead sponsor of 2 studies on the registry; none are open to participants now.
Counted across the registry records on this site, refreshed daily.
To be eligible for this study, a participant must meet all of the following criteria:
Participant has a diagnosis of moderate or severe ARDS:
A participant with a diagnosis of moderate or severe ARDS according to the Berlin definition of ARDS:
i. Moderate ARDS: PaO2/FiO2 more than 100 mmHg (more than 13.3 kPa) to 200 mmHg and below (26.6 kPa and below) with PEEP 5 cmH2O and above, or imputed SpO2/FiO2 equivalent.
ii. Severe ARDS: PaO2/FiO2 100 mmHg and below (13.3 kPa and below) with PEEP 5 cmH2O and above.
OR Participant presents with acute respiratory failure phenotypically similar to ARDS in a setting demonstrating clinical risk for ARDS, whether or not they meet the Berlin criteria, and requiring heated and humidified HFNC 30 L/min and above and 100 percent FiO2, or NIPPV (ie, BiPAP/CPAP) for hypoxemia.
OR Participant presents with acute respiratory failure phenotypically similar to ARDS in a setting demonstrating clinical risk for ARDS, do not meet the Berlin criteria, and initially treated with 12 continuous hours and above with HFNO using gas flow of 40 L/min and above or treated with non-invasive ventilation (NIV), and has a PEEP of 5 cm and above H2O and PaO2/FIO2 below 300 mm Hg.
Exclusion Criteria:
A participant who meets any of the following criteria must be excluded from the study:
Known or suspected active and untreated tuberculosis (TB), HIV, hepatitis B or C infection.
Note: Results of TB, hepatitis B and C, and HIV tests are not required prior to enrollment if there is no suspicion of active infection.
Use of any immunomodulatory biologic (eg, anti-IL-1, anti-IL-6R, anti-TNF, inhibitors of complement signaling), cell therapies (eg, mesenchymal stem cells), or small molecule Janus kinase (JAK) inhibitors within the past 7 days or within 5 half-lives (whichever is longer), or planned use of any of these agents from screening until Day 60 of the study, unless approved by the MM. The following will be allowed/ disallowed as indicated:
Participants who have circulatory shock requiring vasopressors at randomization or within 24 hours prior to randomization will be excluded from study participation.
Participants who present at screening with ARDS and septic shock may be enrolled if the participant is on one vasopressor or, if on 2 vasopressors, if the Levofed (norepinephrine) dose is 1 microgram/kg/min and lesser.
Participants with ARDS and septic shock who are on 3 and above vasopressors ie, Vasopressin, Levofed (norepinephrine), Neosynephrine (phenelephreine), at screening are excluded from study participation.
Participants with ARDS and septic shock who are on 2 vasopressors where the Levofed dose is more than 1 micro gram/kg/min are excluded from study participation.
90 eligible participants will be randomized at a 2:1 ratio to receive a single dose of ALT-100 mAb. Part A will assess 2 doses of ALT-100 mAb in sequentially enrolled cohorts of up to 9 participants in each cohort. (Randomised, Double-blind) Drug: ALT-100 mAb Dosage Form: Sterile liquid, pH 5.5, Dosage: 0.4 mg/kg (Cohort 1a) and 1.0 mg/kg (Cohort 2a) Dosage Form \& Route of Admin: Solution for IV Infusion
Drug: ALT-100 mAb
Part A participants with acute respiratory distress syndrome (ARDS) (Randomised, Double-blind) Dosage Form \& Route of Admin: Normal Saline Solution for IV Infusion
Drug: ALT-100 (Placebo)
Approximately 9 participants in each cohort in Part A, additional participants (up to 36 per dose cohort) may be enrolled into 2 dose expansion cohorts, the dose of which will be determined by the SRC. Drug: AT-02 Dosage: Will be decided by the SCR Route of Admin: Solution for IV Infusion
Drug: ALT-100 mAb
Experimental: Part A : ALT-100 mAB (Dose Escalation) 90 eligible participants will be randomized at a 2:1 ratio to receive a single dose of ALT-100 mAb.
Normal saline solution via IV solution
To evaluate the Safety and tolerability of a single intravenously (IV) infused dose of ALT-100 in participants with moderate to severe ARDS: Incidence and severity of treatment-emergent adverse events (TEAEs) from Day 1 to end of study (EOS).
Assessment will be done by measuring the following parameter: • Incidence and severity of treatment-emergent adverse events (TEAEs) from Day 1 to end of study (EOS).
Time frame: Up to 60 days
To evaluate the impact of a single IV infusion of ALT-100 on respiratory support.
Assessment will be done by measuring Number of Mechanical Ventilation-free days (MVFD) over 28 days following study treatment (ie, MVFDs by Day 29).
Time frame: Up to 29 Days
To assess the effect of ALT-100 on duration of hospitalization: Time to hospital discharge based on days since admission to discharge.
Assessments will be done by: \- Time to hospital discharge based on days since admission to discharge.
Time frame: Up to 29 Days
To assess the effect of ALT-100 on duration of hospitalization: Hospital Free Days (HFD) to Day 29.
Assessments will be done by: \- Hospital Free Days (HFD) to Day 29.
Time frame: Up to 29 Days
To assess the effect of ALT-100mAb as measured by the Sequential Organ Failure Assessment (SOFA) score.
Assessments will be done by: \- Total and component Sequential Organ Failure Assessment (SOFA) score assessed daily while in the intensive care unit (ICU). The score is based on six different scores, one each for the respiratory, cardiovascular, hepatic, coagulation, renal and neurological systems. Score ranges from 0 (best) to 24 (worst) points
Time frame: Up to 29 Days
To assess the effect of ALT-100 mAb on oxygen-related parameters :Changes as measured by change from baseline in plethysmographic pulse oximetry derived oxygen saturation / fraction of inspired oxygen and ROX Index
Assessments will be done by: • Changes as measured by change from baseline in plethysmographic pulse oximetry derived oxygen saturation / fraction of inspired oxygen (SpO2/FiO2) and ROX Index (SpO2/FiO2 divided by respiratory rate \[RR\]), assessed daily while hospitalized.
Time frame: Up to 29 Days
To assess the effect of ALT-100 mAb on oxygen-related parameters: If the participant is receiving MV, the P/F ratio will be used (ie, partial pressure of oxygen [PaO2]/FiO2).
Assessments will be done by: • If the participant is receiving MV, the P/F ratio will be used (ie, partial pressure of oxygen \[PaO2\]/FiO2).
Time frame: Up to 29 Days
To assess the effect of ALT-100 mAb on oxygenation requirements.
Assessments will be done by: \- Incidence and duration of oxygen use (via conventional oxygen therapy, or non-invasive respiratory support positive pressure by face mask or HFNO) during the study.
Time frame: Up to 29 Days
To assess the effect of ALT-100 mAb on requirement for vasoactive support
Assessment will be done by: \- Number of days of vasoactive agent usage Vasopressor free days
Time frame: Up to 29 Days
Pharmacodynamics : To investigate the effects of ALT-100 mAb on immune function biomarkers and cellular response. Changes from baseline in plasma levels of extracellular nicotinamide phosphoribosyl transferase and other biomarkers of interest.
To investigate the effects of ALT-100 mAb on immune function biomarkers and cellular response. Assessments will be done by: \- Changes from baseline in plasma levels of extracellular nicotinamide phosphoribosyl transferase (eNAMPT) and other biomarkers of interest including but not limited to TNF-α, IL-1β, IL-1RA, IL-6, Angiopoietin-2.
Time frame: Up to 29 Days
Pharmacodynamics: To investigate the effects of ALT-100 mAb on immune function biomarkers and cellular response. Changes from baseline in cellular response with ALT-100 compared to placebo.
To investigate the effects of ALT-100 mAb on immune function biomarkers and cellular response. Assessments will be done by: \- Changes from baseline in cellular response with ALT-100 compared to placebo, as assessed by: neutrophil, monocyte, and lymphocyte counts in whole blood.
Time frame: Up to 29 Days
Pharmacokinetics - To characterize the plasma PK profile of single IV infused doses of ALT-100 : Determination of plasma concentrations of ALT-100 mAb.
To characterize the plasma PK profile of single IV infused doses of ALT-100. Assessment will be done to • Determination of plasma concentrations of ALT-100 mAb.
Time frame: Up to 60 days
PK of single IV infused dose of ALT-100
Estimation of PK parameter
Time frame: Up to 60 days
Number of participants with abnormal clinically significant clinical laboratory results
Clinical laboratory tests include hematology, chemistry, coagulation and urinalysis.
Time frame: Up to 60 days
Number of participants with abnormal clinical vital signs
Vital signs include blood pressure, heart rate, respiration rate, body temperature
Time frame: Up to 60 days
To further evaluate the safety and tolerability of a single intravenously(IV) infused dose of ALT-100 mAb through physical examination
Secondary safety and tolerability outcomes while hospitalized or if discharged on Days 8, 15, 22, 29, and 60 will include: • Physical examination
Time frame: Up to 60 days
Safety - To further evaluate the safety and tolerability of a single intravenously (IV) infused dose of ALT-100 mAb: Secondary safety and tolerability outcomes will include: Concomitant medication use
Secondary safety and tolerability outcomes while hospitalized or if discharged on Days 8, 15, 22, 29, and 60 will include: • Concomitant medication use
Time frame: Up to 60 days
Safety - To further evaluate the safety and tolerability of a single intravenously (IV) infused dose of ALT-100 mAb: Secondary safety and tolerability outcomes will include: Oxygenation (FiO2 and PaO2 or SpO2)
Secondary safety and tolerability outcomes while hospitalized or if discharged on Days 8, 15, 22, 29, and 60 will include: • Oxygenation (FiO2 and PaO2 or SpO2)
Time frame: Up to 60 days
Safety - To further evaluate the safety and tolerability of a single intravenously (IV) infused dose of ALT-100 mAb: Secondary safety and tolerability outcomes will include: Ventilation support.
Secondary safety and tolerability outcomes while hospitalized or if discharged on Days 8, 15, 22, 29, and 60 will include: • Ventilation support: heated and humidified high flow nasal O2 \[HFNO\]
Time frame: Up to 60 days
Safety - To investigate the presence of anti-ALT-100 mAb antibodies.
To investigate the presence of anti-ALT-100 mAb antibodies. Assessment will be done by: Presence and characterization of ADA over the study period (baseline \[Day 1 pre-dose\], and post treatment on Days 8, 15, 29, and 60).
Time frame: Up to 60 days
Exploratory: detection of NAMPT genetic variants in blood: Determination of ARDS-associated NAMPT promoter SNP expression in baseline blood samples from all participants using a NAMPT genotyping platform.
Exploratory detection of NAMPT genetic variants in blood Assessment will be done by: \- Determination of ARDS-associated NAMPT promoter SNP expression in baseline blood samples from all participants using a NAMPT genotyping platform.
Time frame: Up to 60 days
Exploratory: detection of NAMPT genetic variants in blood: Assessment of predictive capacity of NAMPT SNPs and plasma eNAMPT levels to identify participants who respond to single dose treatment with ALT-100 mAb.
Exploratory detection of NAMPT genetic variants in blood Assessment will be done by: \- Assessment of predictive capacity of NAMPT SNPs and plasma eNAMPT levels to identify participants who respond to single dose treatment with ALT-100 mAb.
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care: Change from baseline in LIS (if performed) daily while hospitalized.
To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care (eg, LIS, chest radiography, PaO2/FiO2, need for extracorporeal membrane oxygenation \[ECMO\]) Assessments will be done by: \- Change from baseline in LIS (if performed) daily while hospitalized.
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care: Change from baseline in chest radiographic assessment (if performed).
To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care (eg, LIS, chest radiography, PaO2/FiO2, need for extracorporeal membrane oxygenation \[ECMO\]) Assessments will be done by: \- Change from baseline in chest radiographic assessment (if performed).
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care: Change from baseline in P/F ratio (if performed) daily while hospitalized.
To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care (eg, LIS, chest radiography, PaO2/FiO2, need for extracorporeal membrane oxygenation \[ECMO\]) Assessments will be done by: \- Change from baseline in P/F ratio (if performed) daily while hospitalized.
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care (eg, LIS, chest radiography, PaO2/FiO2, need for extracorporeal membrane oxygenation [ECMO]) Utilization of ECMO.
To explore the effect of ALT-100 on other measurements of lung injury that may be performed during standard care (eg, LIS, chest radiography, PaO2/FiO2, need for extracorporeal membrane oxygenation \[ECMO\]) Assessments will be done by: \- Utilization of ECMO.
Time frame: Up to 60 days
Exploratory - To assess the effect of ALT-100 on respiratory support requirements over time: MVFDs by Days 8, 15, 22, and 60.
To assess the effect of ALT-100 on respiratory support requirements over time Assessment will be done by: \- MVFDs by Days 8, 15, 22, and 60.
Time frame: Up to 60 days
Exploratory - To assess the effect of ALT-100 on respiratory support requirements over time: Proportion of participants not on MV support on Days 8, 15, 22, 29, and 60.
To assess the effect of ALT-100 on respiratory support requirements over time Assessment will be done by: \- Proportion of participants not on MV support on Days 8, 15, 22, 29, and 60.
Time frame: Up to 60 days
Exploratory - To assess the effect of ALT-100 on respiratory support requirements over time: Number of participants progressing from non-invasive to invasive MV by Days 8, 15, 22, 29, and 60.
To assess the effect of ALT-100 on respiratory support requirements over time Assessment will be done by: \- Number of participants progressing from non-invasive to invasive MV by Days 8, 15, 22, 29, and 60.
Time frame: Up to 60 days
Exploratory - To assess the effect of ALT-100 on respiratory support requirements over time: Time of progression from non-invasive to invasive MV to Day 60.
To assess the effect of ALT-100 on respiratory support requirements over time Assessment will be done by: \- Time of progression from non-invasive to invasive MV to Day 60.
Time frame: Up to 60 days
Exploratory - To assess the effect of ALT-100 on respiratory support requirements over time: Proportion of participants weaned from MV within 28-days from treatment (by Day 29).
To assess the effect of ALT-100 on respiratory support requirements over time Assessment will be done by: \- Proportion of participants weaned from MV within 28-days from treatment (by Day 29).
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 mAb on mortality: Mortality in all participants by Days 8, 15, 22, 29, and 60.
To explore the effect of ALT-100 mAb on mortality Mortality will be assessed by: \- Mortality in all participants by Days 8, 15, 22, 29, and 60.
Time frame: Up to 60 days
Exploratory - To explore the effect of ALT-100 mAb on mortality: Time to death by Day 60.
To explore the effect of ALT-100 mAb on mortality Mortality will be assessed by: \- Mortality in all participants by Days 8, 15, 22, 29, and 60.
Time frame: Up to 60 days
Plan to share: No — IPD is not being shared with other researchers.
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Respiratory Distress Syndrome→
Aqualung Therapeutics Corp.