A novel, small-volume subcutaneous furosemide formulation delivered by an abdominal patch infusor device in patients with heart failure: results of two phase I studies.

AIMS: Subcutaneous (SC) furosemide has potential advantages over intravenous (IV) furosemide by enabling self-administration or administration by a lay caregiver, such as facilitating early discharge, preventing hospitalizations, and in palliative care. A high-concentration, pH-neutral furosemide formulation has been developed for SC administration via a small patch infusor pump. We aimed to compare the bioavailability, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of a new SC furosemide formulation with conventional IV furosemide and describe the first use of a bespoke mini-pump to administer this formulation. METHODS AND RESULTS: A novel pH-neutral formulation of SC furosemide containing 80 mg furosemide in ∼2.7 mL (infused over 5 h) was investigated. The first study was a PK/PD study of SC furosemide compared with 80 mg IV furosemide administered as a bolus in ambulatory patients with heart failure (HF). The primary outcome was absolute bioavailability of SC compared with IV furosemide. The second study investigated the same SC furosemide preparation delivered by a patch infusor in patients hospitalized with HF. Primary outcome measures were treatment-emergent adverse events, infusion site pain, device performance, and PK measurements.The absolute bioavailability of SC furosemide in comparison to IV furosemide was 112%, resulting in equivalent diuresis and natriuresis. When SC furosemide was administered via the patch pump, there were no treatment-emergent adverse events and 95% of participants reported no/minor discomfort at the infusion site. CONCLUSION: The novel preparation of SC furosemide had similar bioavailability to IV furosemide. Administration via a patch pump was feasible and well tolerated.

A case report of myocardial infarction in a young transgender man with testosterone therapy: raising awareness on healthcare issues in the transgender community and a call for further research.

Background: People who are transgender may utilize masculinizing or feminizing gender-affirming hormonal therapy. Testosterone and oestrogen receptors are expressed throughout the cardiovascular system, yet the effects of these therapies on cardiovascular risk and outcomes are largely unknown. We report the case of a young transgender man with no discernible cardiovascular risk factors presenting with an acute coronary syndrome. Case summary: A 31-year-old transgender man utilizing intramuscular testosterone masculinizing gender-affirming hormonal therapy presented with central chest pain radiating to the left arm. He had no past medical history of hypertension, dyslipidaemia, diabetes, or smoking. Electrocardiography demonstrated infero-septal ST depression, and high-sensitivity troponin-I was elevated and increased to 19 686 ng/L. He was diagnosed with a non-ST-segment elevation myocardial infarction. Inpatient coronary angiography confirmed a critical focal lesion in the mid right coronary artery, which was managed with two drug-eluting stents. Medical management (i.e. aspirin, ticagrelor, atorvastatin, ramipril, and bisoprolol) and surveillance of residual plaque disease evident in the long tubular left main stem, proximal left anterior descending, and proximal circumflex vessels was undertaken. The masculinizing gender-affirming hormonal therapy was continued. Discussion: Despite a greater awareness of the potential risk of increased cardiovascular disease in transgender people, the fundamental lack of data regarding cardiovascular outcomes in transgender people may be contributing to healthcare inequalities in this population. We must implement better training, awareness, and research into transgender cardiovascular health to facilitate equitable and evidence-based outcomes.