Breathing issues; COVID positive with mild infection; COVID positive with mild infection; Nosebleed; This is a solicited report from the marketing program, marketing program not available received from a contactable consumer (patient's wife). An 82-year-old male patient received BNT162B2 (PFIZER-BIONTECH COVID-19 VACCINE), via an unspecified route of administration second dose on 16Feb2021 (Lot number and expiration date was not reported) at single dose, via an unspecified route of administration first dose on 26Jan2021 (Lot number and expiration date was not reported) at single dose for COVID-19 immunization (age at vaccination 82 years old), treprostinil sodium (TYVASO, inhalation gas, strength: 0.6 mg/ml), resp inhalation from 07Aug2018 to an unspecified date, at unknown dose and frequency; then from an unspecified date (Lot Number: 2101911; Expiration Date: 31Oct2021) to an unspecified date, at 4x/day (18-54 mcg, qid) for pulmonary arterial hypertension and treprostinil, resp inhalation from 07Aug2018 to an unspecified date, at 0.6 mg/ml; then from an unspecified date (Lot Number: 2101911; Expiration Date: 31Oct2021) to an unspecified date, at 4x/day (18-54 mcg, qid) for pulmonary arterial hypertension. The patient's medical history included ongoing pulmonary arterial hypertension. The patient's concomitant medication included tadalafil. On 13Mar2021, the patient experienced COVID positive with mild infection, difficulty breathing, and nosebleed. On 31Mar2021, 2 years 7 months 25 days after initiating IH Tyvaso, the patient was readmitted to the hospital for breathing issues. The events COVID positive with mild infection, difficulty breathing was assessed as serious (medically significant and caused hospitalization). The events nosebleed and breathing issues was serious (caused hospitalization). The patient underwent lab tests and procedures which included COVID-19 virus test: positive on 13Mar2021. The action taken for the suspect drugs treprostinil sodium and treprostinil in response to the events was unknown. The outcome of the events was unknown. The reporter did not provided causality for events.  Case Comment/Senders Comment: The company has assessed the serious adverse event of COVID-19, epistaxis and dyspnea as not related to IH treprostinil and TD-300/A device. COVID-19 was likely due to infection with SARS-CoV-2 virus infection during the ongoing COVID-19 pandemic and epistaxis and dyspnea was likely a clinical cascade from COVID infection in setting of underlying PAH in this elderly 82-year-old patient.   The reporter's assessment of the causal relationship of the event with the suspect product was not provided at the time of this report. Since no determination has been received, the case is managed based on the company causality assessment.  Information on the lot/batch number has been requested.  Follow-up (07Apr2021): New information received by Pfizer via United Therapeutics (MFR report #: UNT-2021-004686) from the same contactable consumer (patient's wife) includes: suspect product details (new dosing regimen for treprostinil sodium (TYVASO)), new event (breathing issues) and clinical course details.   Information on the lot/batch number has been requested.  Follow-up (19May2021): This follow-up is being submitted to notify that the lot/batch number is not available despite the follow-up attempts made. Follow-up attempts completed. No further information is expected.; Sender's Comments: Based on the available information, the Company cannot completely exclude the possible causality between the reported COVID- 19 positive with mild infection, which is considered failure of COVID-19 vaccine BNT162B2, and the administration of BNT162B2 vaccine. The Company considers the reported events Nosebleed  and Breathing issues  as  unrelated to BNT162B2 vaccine,  more likely being inter-current medical conditions.