Biscayne Park

Researchers are studying a treatment called MANP modified atrial natriuretic peptide for people with difficult to control or resistant hypertension. This Phase 2 study compares the safety and effects of daily MANP injections to a placebo in reducing daytime systolic blood pressure over 42 days. Participants are adults aged 18 to 80 who are already taking three or more blood pressure medications. Participants will be randomly assigned to receive either MANP or a placebo injection once daily for 42 days. The MANP is given as a subcutaneous injection. The study is double-blind, meaning neither participants nor researchers know who receives the active treatment or placebo until the study ends. A subset of participants with slightly reduced kidney function may also be included, but not exceeding 10% of total enrollment. During the study, participants will have their blood pressure monitored closely using 24-hour ambulatory blood pressure devices and clinic measurements. Safety will be assessed through reports of side effects and serious adverse events up to 4 weeks after treatment ends. Blood samples will be taken for pharmacokinetic and antibody testing. The total study duration includes about 42 days of treatment plus 4 weeks of safety follow-up.