Voxelotor for Improving Oxygen Saturation in Adults

Inclusion Criteria: * Oxygen dependency due to an end-staged lung disease (pre-lung transplant population) or ALI/acute lung injury (for example but not limited to primary allograft dysfunction, infectious pneumonia, aspiration, non-cardiogenic pulmonary edema). ALI will be defined as per Berlin criteria with a P/F ratio \<100 denoting severe ARDS, \<200 denoting moderate and \<300 mild ARDS. ALI and mild ARDS are considered synonymous. In the event of inability to obtain arterial blood gas analysis to calculate a P/F ratio, we will consider a range of patients requiring standard nasal cannulae flowing at 6l/min to maintain SaO2 \>90% as ALI, and Salter High -Flow nasal cannulae at 12-15l/min in order to maintain SaO2\>85% as severe ARDS. * At least 48 hours of stable, increased oxygen requirement or ventilatory support prior to the start of drug administration if consented. Exclusion Criteria: * Minors (\<18 years) * Pre-existing congestive cardiac failure (NYHA III or IV) * Medically significant, non-revascularized coronary artery disease * Inability to obtain informed consent from LAR * Pregnancy * Incarcerated individual. * Failure of another vital organ. * Severe hepatic impairment (Childs-Pugh C) or liver enzymes \> 4x upper limit of normal (ULN) at screening. * Unstable acute kidney injury/rising creatinine. * Chronic neuromuscular disease requiring mechanical ventilation * Not anticipated to survive \>48 hours * Limited therapeutic goals (do not resuscitate, etc.) * History of Pulmonary Embolism (PE) * Requires treatment with Fluconazole or other moderate and strong CYP3A4 inhibitors listed in section 5.6 * A patient with active bleeding complications requiring more than 1 unit of blood transfusion per day, as the PK and PD of Voxelotor in the setting of blood loss and blood transfusion is unknown. * Participated in another clinical trial of an investigational drug (or medical device) within 30 days or 5-half-lives, whichever is longer, prior to consent, or is currently participating in another trial of an investigational or marketed drug (or medical device) * Any condition including the presence of laboratory abnormalities, which places the subject at unacceptable risk if he/she were to participate in the study * Any condition or concomitant medication that confounds the ability to interpret data from the study or safely use Voxelotor.