Cough Reduction in IPF with Nalbuphine ER

Inclusion Criteria:

• Diagnosis of IPF as determined by the Principal Investigator based onATS/ERS/JRS/ALAT guidelines.

• Cough Severity Score ≥ 4 on CS-NRS (Cough Severity Numerical Rating Scale) duringthe Screening period and Baseline.

• History of chronic cough for at least 8 weeks before screening.

• SpO2 ≥ 92%, taken after at least 5 minutes in a sitting position, undisturbed andnon-stimulated (Saturation of Hemoglobin with Oxygen as Measured by Pulse Oximetry).

• FVC ≥ 40% predicted of normal - Forced Vital Capacity, as determined by spirometryadhering to ATS/ERS guidelines.

• DLCO ≥ 25% predicted of normal - Diffusing capacity of the lung for carbon monoxidecorrected for hemoglobin, assessed within the last 12 weeks, or at the time ofscreening.

Exclusion Criteria:

• Currently on continuous oxygen therapy for longer than 16 hours at any level ordelivered by any modality. Intermittent oxygen use of any duration over any given 24-hour period is allowed.

• Inadequate swallow reflex as assessed by the ability to sip 3 fluid oz (or 89 mL) ofwater without coughing or choking.

• Upper or lower respiratory tract infection in the last 8 weeks prior to the baselinevisit.

• Clinical history of aspiration pneumonitis.

• Diagnosis of sleep apnea.

• Abnormal kidney or liver functions based on Screening lab results.

• Known hypersensitivity to nalbuphine or to NAL ER excipients

• History of major psychiatric disorder.

• History of substance abuse.

• Significant medical condition or other factors that may interfere with the subject'sability to successfully complete the study.

• Pregnant or lactating female subject.

• Known intolerance (gastrointestinal, central nervous system symptoms),hypersensitivity, drug allergy following the use of an opioid drug.

• Use of opiates is prohibited within 14 days prior to the baseline visit.

• Use of benzodiazepines are prohibited within 14 days prior to the baseline visit andfor the duration of the study.

• Monoamine oxidase inhibitors (MAOIs) including methylene blue (methylthioniniumchloride) and the antibiotic linezolid are prohibited within 14 days prior to thebaseline visit and for the duration of the study.

• Use of oral corticosteroid cough treatment is prohibited within 4 weeks prior to thebaseline visit and for the duration of the study.

• Exposure to any investigational medication, including placebo, is prohibited within 4 weeks prior to the baseline visit and for the duration of the study.

• Medications prescribed as cough suppressants are prohibited unless on a stable dose 14-days prior to the baseline visit and are expected to remain on that dose for theduration of the study.

• Use of medications that affect serotonergic neurotransmission and that when usedconcomitantly with opioids can increase the risk of serotonin syndrome areprohibited unless on a stable dose 14-days prior to the baseline visit and areexpected to remain on that dose for the duration of the study.

• Anti-fibrotic medications are prohibited unless on a stable dose for 8 weeks priorto the baseline visit and are expected to remain on that dose for the duration ofthe study.

• Strong inhibitors/inducers of the P450 Isozymes are prohibited unless on a stabledose for 14-days prior to baseline visit and are expected to remain on that dose forthe duration of the study.

• Use of a medication having a "known risk" of Torsade de Pointes (categorized as "KR"on the Credible Meds® website.) 4 weeks prior to Baseline.

• Use of unstable doses of medications associated with a potential risk of QTprolongation but not clearly associated with Torsade de Pointes within 4 weeks ofscreening.